Resin intermediate, low-amine-value resin intermediate and preparation method and production system thereof

Abstract

The invention discloses a resin intermediate, a low-amine-value resin intermediate and a preparation method and a production system thereof, and the preparation method comprises the following steps: step 1, carrying out degradation reaction on an initial polymer and a degradation agent with an active group to break at least a part of molecular chains of the initial polymer, preparing a resin intermediate containing an initial polymer molecular chain fragment with an active group; the mixing mode of the polyurethane waste and the degradation agent comprises but is not limited to one or combination of more of high-speed stirring, centrifugal stirring, kneading, mixing, screw extrusion, grinding and ball milling; the degradation reaction time is 1 to 5 minutes, 5 to 10 minutes, 10 to 15 minutes, 15 to 20 minutes, 20 to 25 minutes, 25 to 30 minutes, 30 to 60 minutes, 60 to 90 minutes, 90 to 120 minutes, 120 to 180 minutes, 180 to 240 minutes, 240 to 300 minutes, 300 to 360 minutes or 360 to 480 minutes. The inventor innovatively adopts the step of mixing or extruding the polyurethane solid waste by matching with proper parameters and equipment, so that the wall breaking and volume reduction of the polyurethane solid waste are realized, the microporous structure of the polyurethane solid waste is damaged, the mixing efficiency and heat transfer efficiency of the degradation agent and the polyurethane solid waste are promoted, the solid-liquid ratio is increased, and the degradation time is shortened.

Description

Technical Field

[0001] The invention relates to the field of polymer technology, and in particular to a resin intermediate, a low amine value resin intermediate, and a preparation method and a production system thereof. Background Art

[0002] Polyurethane is a polymer material widely used in various fields. The treatment and reuse of its waste is an important environmental issue. The traditional chemical recycling method of polyurethane waste requires the use of a large amount of degradation agents to react with solid waste. The solid waste content is low, the degradation efficiency is low, and the long-term high-temperature heating causes an increase in aniline by-products, which does not meet the requirements of downstream applications. How to increase the solid-liquid ratio and reduce the degradation time has become the key to reducing the product amine value and improving the quality of recycled polyurethane products. Summary of the invention

[0003] The purpose of the present invention is to provide a resin intermediate, a low amine value resin intermediate and a preparation method and a production system thereof, so as to achieve the purpose of increasing the solid-liquid ratio and reducing the degradation time.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0005] A method for preparing a resin intermediate comprises the following steps: step A: subjecting an initial polymer to a degradation agent with an active group for degradation reaction, breaking at least a portion of the molecular chains of the initial polymer, and obtaining a resin intermediate containing molecular chain fragments of the initial polymer with the active group; the mixing method of the polyurethane waste and the degradation agent comprises but is not limited to a combination of one or more of high-speed stirring, centrifugal stirring, kneading, mixing, screw extrusion, grinding, and ball milling; and the degradation reaction time is 1-5 min, 5-10 min, 10-15 min, 15-20 min, 20-25 min, 25-30 min, 30-60 min, 60-90 min, 90-120 min, 120-180 min, 180-240 min, 240-300 min, 300-360 min or 360-480 min.

[0006] Furthermore, the initial polymer is polyurethane waste.

[0007] The present invention has found through a large number of experiments that the polyurethane solid waste (hereinafter referred to as polyurethane solid waste) as the initial polymer has a large number of micropores and a density of generally less than 0.08 g / cm 3 , often float on the surface of the degradation agent, making it difficult for the degradation agent to penetrate into the pores, and the thermal insulation properties of these microporous structures also make it impossible for the polyurethane solid waste to be heated evenly. Therefore, a large amount of degradation agent is required to mix evenly and degrade the reaction, and the mass ratio of solid-liquid mixing is often less than 1:4.

[0008] The inventors innovatively adopt the mixing or extrusion steps of the polyurethane solid waste with appropriate parameters and equipment, thereby breaking the wall and reducing the volume of the polyurethane solid waste and destroying the microporous structure of the polyurethane solid waste, thereby promoting the mixing efficiency and heat transfer efficiency of the degradation agent and the polyurethane solid waste, increasing the solid-liquid ratio, and reducing the degradation time, thereby solving the above technical problems.

[0009] 1. Preparation of activated polyurethane by crushing

[0010] A method for preparing a modified polymer as an activated polyurethane, wherein the modified polymer is obtained by treating an initial polymer, wherein the treatment comprises the following steps: Step A: before the initial polymer and a degradation agent are subjected to degradation reaction to prepare a resin intermediate, polyurethane waste is subjected to pulverization treatment to obtain an activated polyurethane, wherein the pulverization treatment includes but is not limited to one or a combination of multiple methods such as crushing, shearing, grinding, ball milling, grinding, air flow pulverization, and ultrasonic pulverization; the initial polymer is polyurethane waste; wherein the pulverization treatment equipment comprises one or a combination of two of an internal mixer or a screw extruder.

[0011] Furthermore, the internal mixer has a clamping component, which applies an additional extrusion force to the material in the internal mixer in addition to the internal mixing roller during the internal mixing process. The clamping component applies the additional extrusion force to the material through a combination of one or more effects of gravity, mechanical force, oil pressure, and air pressure.

[0012] 1.1. Crushing treatment by screw extruder

[0013] Step A includes the following steps:

[0014] Step A1: adding the initial polymer into the screw extruder and subjecting it to the pulverization treatment to obtain an extruded product as the modified polymer; the pulverization treatment includes one or more combinations of crushing, shearing, grinding, ball milling or grinding. The extruded product can be used as an activated polyurethane to directly participate in the preparation of resin derivative products.

[0015] Further, the screw extruder includes a single-screw extruder or a twin-screw extruder; further, the extrusion time of the material in the screw extruder is 10-20s, 20-40s, 40-60s, 60-80s, 80-100s, 100-120s, 120-160s, 160-200s, 200-240s, 240-300s, 300-360s or 360-480s. Furthermore, the screw speed of the screw extruder is set to 5-10rpm, 10-20rpm, 20-30rpm, 30-40rpm, 40-50rpm, 50-60rpm, 60-70rpm, 70-80rpm, 80-100rpm or 100-200rpm; further, the conveying section temperature of the screw extruder is set to 15-30℃, 30-40℃, 40-50℃, 50-60℃, 60-70℃ , 70-80℃ or 80-90℃; further, the extrusion section temperature of the screw extruder is set to 15-20℃, 20-40℃, 40-60℃, 60-80℃, 80-100℃, 100-120℃, 120-160℃, 160-200℃ or 200-230℃; and / or the die head temperature of the screw extruder is set to 60-90℃, 90-120℃, 120-150℃, 150-180℃ or 180-210℃.

[0016] 1.2. Internal mixer crushing

[0017] Step A comprises the following steps: Step A2: adding the initial polymer into the internal mixer and performing the pulverization treatment to obtain a internal mixing product as the modified polymer, wherein the temperature in the internal mixer is -10-10°C, 10-15°C, 15-30°C, 30-40°C, 40-50°C, 50-60°C, 60-70°C, 70-80°C, 80-90°C, 90-100°C, 100-150°C or 150-230°C. The internal mixing product can be used as an activated polyurethane to directly participate in the preparation of resin derivative products.

[0018] Further, in step A2, the mixing time is controlled to be 1-5 min, 5-10 min, 10-15 min, 15-20 min, 20-25 min, 25-30 min or 30-90 min; further, the stirring speed of the internal mixer is 5-10 rpm, 10-20 rpm, 20-30 rpm, 30-40 rpm, 40-50 rpm, 50-60 rpm, 60-70 rpm, 70-80 rpm, 80-90 rpm. rpm, 90-100rpm, 100-300rpm, 300-400rpm, 400-600rpm, 600-800rpm or 800-1000rpm; preferably, the internal mixer is provided with a pressing component, and the pressing component applies an additional squeezing force to the material in addition to the internal mixing roller during the internal mixing process to improve the internal mixing efficiency, and the pressing component applies an additional squeezing force to the internal mixing material through a combination of one or more effects of gravity, mechanical force, oil pressure, and air pressure. Since the polyurethane solid waste has a small density and a microporous structure, it is a fluffy material. If it is not pressed, the friction between the materials is insufficient, which will lead to insufficient internal mixing efficiency, long internal mixing time, high internal mixing temperature, energy consumption and side reactions.

[0019] 1.2.1. Extrusion of mixed products

[0020] Step A also includes the following steps:

[0021] Step A2: adding the initial polymer into the internal mixer and performing the pulverization treatment to obtain an internal mixer product;

[0022] Step A3: adding the internal mixing product obtained in step A2 to the screw extruder for extrusion or extruding through a screw arranged at the bottom of the internal mixer to obtain an extruded product as the modified polymer; wherein the extruded product can be directly used as an activated polyurethane to participate in the preparation of resin derivative products. The extrusion step can further destroy the microporous structure of the initial polyurethane, increase the density of the activated polyurethane, and also has the effect of shaping and further degradation;

[0023] or

[0024] Step A1: adding the initial polymer into the screw extruder and performing the pulverization treatment to obtain an extruded product;

[0025] Step A4: adding the extruded product to the internal mixer for the pulverization treatment to obtain the internal mixing product as the modified polymer. The internal mixing product can be directly used as an activated polyurethane to participate in the preparation of resin derivative products. The addition of the extrusion step can further destroy the microporous structure of the initial polyurethane, increase the density of the activated polyurethane, and also has the effect of shaping and further degradation.

[0026] Further, the screw extruder includes a single screw extruder or a twin screw extruder; further, the extrusion time of the screw extruder is 10-20s, 20-40s, 40-60s, 60-80s, 80-100s, 100-120s, 120-160s, 160-200s, 200-240s, 240-300s, 300-360s or 360-480s. Furthermore, the screw speed of the screw extruder is set to 5-10rpm, 10-15rpm, 15-20rpm, 20-30rpm, 30-40rpm, 40-50rpm, 50-60rpm, 60-70rpm, 70-80rpm or 80-100rpm; further, the conveying section temperature of the screw extruder is set to 15-20℃, 20-30℃, 30-40℃, 40-50℃, 50-60℃, 60-70℃, 70-80rpm or 80-100rpm; 0°C, 80-90°C or 90-100°C; further, the extrusion section temperature of the screw extruder is set to 15-20°C, 20-30°C, 30-40°C, 40-60°C, 60-80°C, 80-100°C, 100-130°C, 130-160°C, 160-200°C or 200-230°C; and / or the die head temperature of the screw extruder is set to 60-90°C, 90-120°C, 120-150°C, 150-180°C or 180-210°C.

[0027] 1.2.2. Add activator and mix well

[0028] In the step A2, the initial polymer and the activator are mixed together in the internal mixer to obtain the internal mixer product; further, the activator includes a compound containing one or more functional groups of hydroxyl, amine, carboxyl or anhydride groups, and the compound includes a single compound containing multiple functional groups or a combination of multiple compounds containing multiple functional groups; the mixing ratio of the polyurethane waste to the activator is 100:5-10, 100:10-15, 100:15 -20, 100:20-25, 100:25-30, 100:30-35, 100:35-40, 100:40-45, 100:45-50, 100:50-80, 100:80-110, 100:110-140, 100:140-170, 100:170-200, 100:200-300, 100:300-400 or 100:400-500. The banburying product of this step can be used as an activated polyurethane to directly participate in the preparation of resin derivative products.

[0029] During the internal mixing process, all materials are mixed in a closed cavity, which makes it easy to mix the polyurethane solid waste and the activator evenly. Especially when the solid-liquid ratio is large, the traditional stirring method cannot mix evenly. The open mixing method does not have a pressing component, so the fluffy polyurethane solid waste cannot be mixed evenly with the activator. Even a long time of open mixing has a low efficiency. When the screw extrusion method is used, fluffy and bulky polyurethane materials are prone to material bridging, and it is also difficult to achieve efficient and uniform solid-liquid mixing. The present invention preferably uses an internal mixing device with a pressing component to apply additional extrusion force to the material during the internal mixing process. Even large pieces of fluffy materials and mixtures with a large solid-liquid ratio can be fed at one time, and there is no problem of material bridging and uneven mixing, and efficient and uniform mixing can be achieved.

[0030] Since a large amount of heat is generated during the banburying process, uncontrollable side reactions are likely to occur. The present invention further adopts a banburying step in which an activator is mixed with the polyurethane solid waste. The heat generated during the banburying process is absorbed by the activator, which can not only reduce side reactions, but also enable the activator to utilize the energy of the banburying process to react with the polyurethane solid waste to cause a certain degree of degradation, and can also reduce the phenomenon of dust flying during the production process.

[0031] The traditional alcoholysis method uses polyurethane solid waste and a degradation agent to mix for degradation. The higher the solid-liquid ratio, the higher the viscosity, the more difficult the mixing, and the solid-liquid ratio reaction of more than 1:1 cannot be achieved. The degradation agent can only be heated and gradually added to the polyurethane solid waste. After one batch of polyurethane solid waste is liquefied, the next batch is added, which greatly prolongs the reaction time. Compared with the existing method of manufacturing degradable polyurethane polyol by conventional alcoholysis, the scheme of the present invention can put the initial polyurethane and the activator into the banburying at one time, mix them evenly during extrusion, have a higher solid-waste ratio, and a lower reaction time, so that the cost of regenerated polyurethane can be reduced; at the same time, even under the same solid-liquid ratio, according to the scheme of the present invention, the reaction time can be shortened and the amine value of the reaction product can be lower, indicating that there are fewer aniline by-products, so that the quality of the regenerated polyurethane can be improved.

[0032] Further, in step A2, the activator includes a polyol or an alcohol composition,

[0033] Further, the polyol includes any one or more combinations of polyether polyol, sucrose polyol, sorbitol, ethylene glycol, butanediol, diethylene glycol, triethylene glycol, hexanediol, polyethylene glycol, propylene glycol, polypropylene glycol, 3-methyl-1,5-pentanediol, 1,9-nonanediol, neopentyl glycol, and glycerol;

[0034] Furthermore, the alcohol composition includes any one or more combinations of polyols, metal reagents, carboxylic acid reagents or anhydride reagents, and the metal reagent includes a potassium reagent.

[0035] 1.2.3. Add activator and knead the product for extrusion

[0036] Step A also includes the following steps:

[0037] Step A2: adding the initial polymer to the internal mixer and performing the pulverization treatment to obtain an internal mixer product; wherein in the step A2, the initial polymer is mixed with an activator in the internal mixer to obtain the internal mixer product; step A3: adding the internal mixer product obtained in the step A2 to the screw extruder for extrusion or extruding through a screw arranged at the bottom of the internal mixer to obtain an extruded product as the modified polymer; wherein the extruded product can be directly used as an activated polyurethane to participate in the preparation of resin derivative products; the extrusion step can further destroy the microporous structure of the initial polyurethane, increase the density of the activated polyurethane, and also has the effect of shaping and further degradation;

[0038] or

[0039] Step A1: adding the initial polymer to the screw extruder for the pulverization treatment to obtain an extruded product; Step A4: adding the extruded product to the internal mixer for the pulverization treatment to obtain a internal mixing product, wherein the extruded product is mixed with an activator in the internal mixer to obtain the internal mixing product as the modified polymer. The internal mixing product can be directly used as an activated polyurethane to participate in the preparation of resin derivative products. The extrusion step can further destroy the microporous structure of the initial polyurethane, increase the density of the activated polyurethane, and also has the effect of shaping and further degradation.

[0040] Furthermore, the screw extruder includes a single-screw extruder or a twin-screw extruder; further, the extrusion time of the material in the screw extruder is 10-20s, 20-40s, 40-60s, 60-80s, 80-100s, 100-120s, 120-160s, 160-200s, 200-240s, 240-300s, 300-360s or 360-480s.

[0041] Further, the screw speed of the screw extruder is set to 5-10rpm, 10-20rpm, 20-30rpm, 30-40rpm, 40-50rpm, 50-60rpm, 60-70rpm, 70-80rpm, 80-100rpm or 100-200rpm;

[0042] Further, the temperature of the conveying section of the screw extruder is set to 15-30°C, 30-40°C, 40-50°C, 50-60°C, 60-70°C, 70-80°C, 80-90°C, 90-100°C or 100-120°C;

[0043] Further, the extrusion section temperature of the screw extruder is set to 15-20°C, 20-40°C, 40-60°C, 60-80°C, 80-100°C, 100-120°C, 120-160°C, 160-200°C or 200-230°C;

[0044] and / or

[0045] The die temperature of the screw extruder is set to 60-90°C, 90-120°C, 120-150°C, 150-180°C or 180-210°C.

[0046] Banbury mixing is closed mixing, and a closed mixer is referred to as a banbury mixer. It has a closed cylindrical container, i.e., a banbury mixing chamber. Usually, a pair of rotors rotating in opposite directions are installed in the banbury mixing chamber, and the rotation of the rotors is used to give the material an extrusion effect. The material temperature can be adjusted by heating or cooling, and it is used for mixing plastics or rubber. The advantage of this mixer is that it has the minimum risk of dust flying and smoke spreading. Preferably, a banbury mixer with a clamping component is used. During the banbury mixing process, the clamping component compresses the banburying material through one or more combinations of gravity, mechanical force, oil pressure or air pressure to prevent the material, especially the foaming material, from becoming fluffy and causing the banburying efficiency to decrease. This method of applying additional pressure to the material in addition to the banburying roller during banburying can greatly reduce the banburying time and improve the banburying efficiency.

[0047] Due to the extrusion and mixing action of the mixing rotor and the additional extrusion force of the pressing component, the initial polymer pore wall is broken, the molecular chain is partially broken, and an activated polyurethane is obtained. At the same time, the activation speed is increased by appropriately increasing the temperature, and excessive degradation caused by excessive temperature is avoided to produce too many by-products. In the present invention, the activator includes a degradation agent that can react with the initial polymer and has a degradation function. The pulverization treatment of the present invention is used as a pretreatment method for the initial polymer before the degradation reaction, and the prepared activated polyurethane itself also participates in the degradation reaction as the initial polyurethane to prepare a resin intermediate.

[0048] The particle size of the activated polyurethane is not less than 40 mesh, preferably greater than 40 mesh, and cannot pass through a sieve with a mesh size of more than 40 mesh. The term "not less than or greater than 40 mesh" in the present invention refers to powders or liquids that cannot pass through a 40 mesh sieve. The scheme of the present invention is significantly different from the existing methods of manufacturing activated micropowders by conventional screw extrusion or open milling. The products of the prior art are powdery and have a particle size of less than 40 mesh, and can pass through a sieve with a mesh size of more than 40 mesh. And the density of the activated polyurethane is ≥0.08g / cm 3 , preferably ≥ 0.2 g / cm 3. The particle size is large, dust is not easy to fly, health and safety risks are reduced, and production operations are safer. Since polyurethane powder with too fine a particle size is flammable, explosive, and easy to absorb moisture, the particle size of the activated polyurethane of the present invention is controlled to be not less than or greater than 40 meshes, which reduces the possibility of flammability and explosion, and is better preserved, convenient for storage and transportation, and reduces transportation costs. Finally, the large particle size of the activated polyurethane of the present invention means that the specific surface area is smaller and less likely to absorb moisture. At the same time, the high density means that the microporous structure is much more destroyed, and a large amount of degradation agent is not required for subsequent degradation reaction. Degradation can be carried out, and the proportion of solids in the mixing ratio with the degradation agent can be higher, so that a more efficient degradation reaction can be carried out at a lower cost, thereby improving production efficiency.

[0049] Furthermore, the activated polyurethane or resin intermediate has a hydroxyl value of 5-800 mg KOH / g, and the amine value of the resin intermediate is 0-20, 20-40, 40-80, 80-200 or 200-500 mg KOH / g.

[0050] Furthermore, the activated polyurethane does not contain R1-NH-CO-R2 groups. This is because the degradation time is short, the side reactions are few, the amine value is low, and the amine can be removed without anhydride, so an activated polyurethane without amide groups can be obtained.

[0051] The present invention also provides a production system applied to any one of the above-mentioned preparation methods, the production system includes the internal mixer, the internal mixer is provided with a clamping component, the clamping component applies an additional extrusion force to the material in the internal mixer in addition to the internal mixing roller during the internal mixing process, the clamping component applies the additional extrusion force to the material through a combination of one or more effects of gravity, mechanical force, oil pressure, and air pressure.

[0052] Furthermore, the internal mixer is provided with a pressure control device and / or a condensing device. The pressure control device includes a pressure relief valve for controlling the pressure in the internal mixer not to exceed a set safety value. The condensing device is used to collect the steam condensation in the internal mixer and return it to the internal mixer.

[0053] 2. Activated polyurethane degradation to obtain resin intermediates

[0054] Step A also includes the following steps:

[0055] Step A: crushing the initial polymer to obtain activated polyurethane; the particle size of the activated polyurethane is not less than 40 meshes, and the activated polyurethane product form includes but is not limited to one or more of paste, granules, blocks, strips, sheets, lumps, powders or floccules;

[0056] Further, step A: the initial polymer is pulverized to obtain activated polyurethane; the pulverization includes but is not limited to one or more combinations of crushing, shearing, grinding, ball milling, grinding, air flow pulverization, ultrasonic pulverization, etc.; the initial polymer is polyurethane waste; wherein the pulverization equipment includes one or a combination of two of an internal mixer or a screw extruder;

[0057] Step B: subjecting the activated polyurethane obtained in step A to a degradation reaction with a degradation agent containing an active group to break at least a portion of the molecular chain of the activated polyurethane to form a resin intermediate containing initial polymer molecular chain fragments with active groups; the degradation reaction is an alcoholysis reaction.

[0058] Further, the degradation agent contains hydroxyl groups; the mixing ratio of the activated polyurethane to the degradation agent is 100:5-10, 100:10-15, 100:15-20, 100:20-25, 100:25-30, 100:30-35, 100:35-40, 100:40-45, 100:45-50, 100:50-80, 100:80-110, 100:110-140, 100:140-170, 100:170-200, 100:200-300, 100:300-400 or 100:400-500; the alcoholysis reaction temperature is 120-160°C, 160-180°C, 180-230°C or 230-260°C. Because the activated polyurethane has a large particle size and high density, it is easy to mix and transfer heat, so it can shorten the degradation time and reduce the amine value of the resin intermediate.

[0059] 3. Degradation of polyurethane waste to obtain resin intermediates

[0060] 3.1. Mixing and degradation of polyurethane waste and degradation agent

[0061] Step A includes the following steps: Step C: adding the initial polymer and the degradation agent with active groups into an internal mixer for mixing, breaking at least a portion of the molecular chain of the initial polymer, and obtaining a resin intermediate containing molecular chain fragments of the initial polymer with active groups, wherein the initial polymer is polyurethane waste. The polyurethane waste directly participates in the degradation reaction as the initial polyurethane.

[0062] 3.1.1. Mixing of polyurethane waste in internal mixer

[0063] Step C comprises the following steps: Step C1: adding polyurethane waste and a degradation agent with an active group into an internal mixer to obtain an internal mixer product, wherein the internal mixer product can be directly used as a resin intermediate to prepare resin derivative products.

[0064] 3.1.2 Extrusion of mixed products

[0065] Step C includes the following steps:

[0066] Step C1: adding polyurethane waste and a degradation agent with an active group into an internal mixer to obtain an internal mixer product.

[0067] Step C2: Add the internal mixing product obtained in step C1 into a screw extruder for extrusion or extrude it through a screw arranged at the bottom of the internal mixer to obtain an extruded product. The extruded product can be directly used as a resin intermediate in the preparation of resin derivative products.

[0068] The initial polyurethane of the mixed product is fed into a screw extruder. Through further extrusion of the screw, the degradation product can be further compressed or reacted or extruded to shape, which is beneficial for subsequent further processing.

[0069] 3.2. Extrusion degradation of polyurethane waste and degradation agent

[0070] Step A includes the following steps: Step D: adding the initial polymer and the degradation agent with active groups into a screw extruder for mixing, breaking at least a portion of the molecular chains of the initial polymer, and obtaining a resin intermediate containing initial polymer molecular chain fragments with active groups, wherein the initial polymer is polyurethane waste.

[0071] 3.2.1. Mixing of polyurethane waste in a screw extruder

[0072] Step D comprises the following steps: Step D1: adding polyurethane waste and a degradation agent with an active group into a screw extruder for extrusion to obtain an extrusion product, wherein the extrusion product can be directly used as a resin intermediate in the preparation of resin derivative products.

[0073] 3.2.2. Mixing of extruded products

[0074] Step D comprises the following steps:

[0075] Step D1: adding polyurethane waste and a degradation agent with an active group into a screw extruder for extrusion to obtain an extruded product.

[0076] Step D2: Add the extruded product obtained in step D1 into an internal mixer to obtain an internal mixer product, wherein the internal mixer product can be directly used as a resin intermediate to prepare resin derivative products.

[0077] Since the pores of the initial polyurethane have been destroyed, the degradation agent can quickly penetrate into the initial polyurethane, the degradation efficiency is high, and the reaction time is short, so that the aniline by-products in the reaction product are less and the amine value is low.

[0078] 4. Mixed amine removal reaction to obtain low amine value resin intermediate

[0079] The present invention also provides an activated polyurethane or resin intermediate with a low amine value, which can be deamined by using the product of the above-mentioned banburying method or screw extrusion method, wherein the amine value of the activated polyurethane or resin intermediate with a low amine value is not higher than 50 mgKOH / g, and further, the activated polyurethane or resin intermediate contains a R1-NH-CO-R2 group. In this way, even without using anhydride to deamine, a product with high viscosity and low amine value can be obtained.

[0080] 4.1. Activated polyurethane mixed with amine removal

[0081] Step A comprises:

[0082] Step A: crushing the initial polymer to obtain activated polyurethane; the particle size of the activated polyurethane is not less than 40 meshes, and the activated polyurethane product form includes but is not limited to one or more of paste, granules, blocks, strips, sheets, lumps, powders or floccules;

[0083] Further, step A comprises: pulverizing the initial polymer to obtain activated polyurethane; the pulverizing includes but is not limited to one or a combination of crushing, shearing, grinding, ball milling, grinding, air flow pulverizing, ultrasonic pulverizing, etc.; the initial polymer is polyurethane waste; wherein the pulverizing equipment used includes one or a combination of two of an internal mixer or a screw extruder;

[0084] Step E1: mixing the activated polyurethane and the acid anhydride to perform an amine removal reaction to obtain the low amine value activated polyurethane;

[0085] Further, the mixing ratio of the acid anhydride to the activated polyurethane is 1-10:100, 10-20:100, 20-30:100, 30-40:100, 40-50:100, 50-60:100, 60-80:100 or 80-100:100; the acid anhydride includes one or more of succinic anhydride, maleic anhydride, phthalic anhydride and methyltetrahydrophthalic anhydride; the temperature of the deamine reaction is 20-30°C, 30-40°C, 40-50°C, 50-60°C, 60-70°C, 70-80°C, 80-90°C, 90-100°C, 100-120°C, 120-150°C, 150-180°C, 180-230°C or 230-250°C, and the amine removal reaction time is 1-5min, 5-10min, 10-20min, 20-30min, 30-40min, 40-50min, 50-80min, 80-120min or 120-240min.

[0086] Furthermore, step A and / or step E1 are prepared in a production system, which includes the internal mixer, and the internal mixer has a clamping component, which applies an additional extrusion pressure to the material in the internal mixer in addition to the internal mixing roller during the internal mixing process, and the clamping component applies the additional extrusion pressure to the material through a combination of one or more effects of gravity, mechanical force, oil pressure, and air pressure.

[0087] The present invention claims protection for the low amine value activated polyurethane prepared by any one of the above preparation methods.

[0088] 4.2. Resin intermediates are mixed and amine is removed to obtain low amine value resin intermediates

[0089] The low amine value resin intermediate comprises the following steps to prepare:

[0090] Step E2: mixing the resin intermediate obtained by any of the above methods with an acid anhydride to remove amines to obtain a low amine value resin intermediate;

[0091] Furthermore, the mixing ratio of the acid anhydride to the resin intermediate is 1-10:100, 10-20:100, 20-30:100, 30-40:100, 40-50:100, 50-60:100, 60-80:100 or 80-100:100.

[0092] 4.2.1. Mixing method of resin intermediate and acid anhydride

[0093] Step E2 comprises: Step E21: adding the resin intermediate and the acid anhydride into an internal mixer to carry out an amine removal reaction to obtain a low amine value resin intermediate;

[0094] Alternatively, step E22: adding the resin intermediate and the acid anhydride into a screw extruder to perform an amine removal reaction to obtain a low amine value resin intermediate.

[0095] Furthermore, in step E21, step A, step B and / or step E2 are prepared in a production system, and the production system includes the internal mixer, and the internal mixer has a clamping component, and the clamping component applies an additional extrusion pressure to the material in the internal mixer in addition to the internal mixing roller during the internal mixing process, and the clamping component applies the additional extrusion pressure to the material through a combination of one or more effects of gravity, mechanical force, oil pressure, and air pressure.

[0096] Further, in step E21, the speed of the internal mixer is 5-20 rpm, 20-30, 30-40, 40-50, 50-60, 60-70, 70-80, 80-100, 100-120, 120-240, 240-360, 360-480, 480-800 or 800-1000 rpm.

[0097] Furthermore, the acid anhydride includes one or more of succinic anhydride, maleic anhydride, phthalic anhydride, and methyltetrahydrophthalic anhydride;

[0098] Further, the temperature of the amine removal reaction is 20-30°C, 30-40°C, 40-50°C, 50-60°C, 60-70°C, 70-80°C, 80-90°C, 90-100°C, 100-120°C, 120-150°C, 150-180°C, 180-230°C or 230-250°C,

[0099] Furthermore, the reaction time for removing amine is 1-5 min, 5-10 min, 10-20 min, 20-30 min, 30-40 min, 40-50 min, 50-80 min, 80-120 min or 120-240 min.

[0100] The present invention further claims protection for a low amine value resin intermediate prepared by any one of the above preparation methods.

[0101] Since many acid anhydrides are solid at room temperature, in the traditional method, when the viscosity of the initial polyurethane or resin intermediate containing amino compounds such as aniline by-products is relatively high, it is difficult to mix them evenly with the acid anhydride, and the compound and the acid anhydride must be heated, which will produce some side reactions such as esterification reactions, consume the acid anhydride, and produce by-products such as long-chain or branched polyesters, and the effect of the deamine reaction cannot be guaranteed. By adopting the scheme of the present invention, the compound and the acid anhydride are put into an internal mixer at low temperature for internal mixing. Even if the viscosity is high, they can be mixed evenly in a short time and the reaction is complete. The side reactions caused by high temperature are also avoided, so that the deamine reaction can be complete.

[0102] Further, the operating parameters of the internal mixer used in the preparation method of any one of the above activated polyurethanes, resin intermediates, low amine value activated polyurethanes or low amine value resin intermediates include: the temperature in the internal mixer is -10-10°C, 10-15°C, 15-30°C, 30-40°C, 40-50°C, 50-60°C, 60-70°C, 70-80°C, 80-90°C, 90-100°C, 100-150°C or 150-230°C; further, the internal mixer time is controlled to be 1-5min, 5-10min, 10-15min, 1 5-20min, 20-25min, 25-30min or 30-90min; further, the stirring speed of the internal mixer is 5-10rpm, 10-20rpm, 20-30rpm, 30-40rpm, 40-50rpm, 50-60rpm, 60-70rpm, 70-80rpm, 80-90rpm, 90-100rpm, 100-300rpm, 300-400rpm, 400-600rpm, 600-800rpm or 800-1000rpm. When the temperature is lower and the stirring speed is lower, the side reaction products are less, but the reaction time will be longer. Higher temperature and higher speed can reduce the reaction time and improve efficiency. Optimization of temperature, speed and internal mixing time can meet the quality requirements of downstream applications.

[0103] Furthermore, the screw extruder used in any of the above-mentioned methods for preparing activated polyurethane, resin intermediate, low-amine value activated polyurethane or low-amine value resin intermediate is used to perform one or a combination of crushing, compression, shaping, further activation, and degradation.

[0104] Further, the operating parameters of the screw extruder used in the preparation method of any one of the above activated polyurethanes, resin intermediates, low amine value activated polyurethanes or low amine value resin intermediates include: the screw extruder includes a single screw extruder or a twin screw extruder; further, the screw speed of the screw extruder is set to 5-10rpm, 10-20rpm, 20-30rpm, 30-40rpm, 40-50rpm, 50-60rpm, 60-70rpm or 70-80rpm; further, the conveying section temperature of the screw extruder is set to 15 -30°C, 30-40°C, 40-50°C, 50-60°C, 60-70°C, 70-80°C or 80-90°C; further, the extrusion section temperature of the screw extruder is set to 15-20°C, 20-40°C, 40-60°C, 60-80°C, 80-100°C, 100-120°C, 120-160°C, 160-200°C or 200-230°C; and / or the die head temperature of the screw extruder is set to 60-90°C, 90-120°C, 120-150°C, 150-180°C or 180-210°C.

[0105] Further, the degradation reaction of any one of the above activated polyurethanes, resin intermediates, low amine value activated polyurethanes or low amine value resin intermediate preparation methods is an alcoholysis reaction; the degradation agent contains a hydroxyl group; the mixing ratio of the polyurethane waste and the degradation agent is 100:5-10, 100:10-15, 100:15-20, 100:20-25, 100:25-30, 100:30-35, 100:35-40, 100: :40-45, 100:45-50, 100:50-80, 100:80-110, 100:110-140, 100:140-170, 100:170-200, 100:200-300, 100:300-400 or 100:400-500; the alcoholysis temperature is 120-160°C, 160-180°C, 180-230°C or 230-260°C.

[0106] Furthermore, the present invention claims protection for the activated polyurethane prepared by any one of the above methods.

[0107] The particle size of the activated polyurethane is not less than 40 meshes, and the sieve residue method is used for detection. The larger the particle size, the smaller the specific surface area, the smaller the proportion of the degradation agent required for mixing with it, and it is safer, healthier, and does not absorb moisture. The form of the activated polyurethane product includes but is not limited to one or more of paste, granular, block, strip, sheet, lump, powder or flocculent.

[0108] Furthermore, the density of the activated polyurethane is greater than or equal to 0.2 g / cm 3The activated polyurethane can be placed in a plastic bag and vacuumed to remove air, and then the drainage volume V can be measured by the drainage method. The density of the activated polyurethane can be obtained by dividing the weight of the activated polyurethane by the difference between the drainage volume and the volume of the plastic bag. The preferred density range is 0.08-0.11 g / cm 3 , 0.11-0.21g / cm 3 , 0.21-0.38g / cm 3 , 0.38-0.81g / cm 3 or 0.81-1.8g / cm 3 The increase in density indicates that the microporous structure is more destroyed, which can reduce transportation costs, reduce specific surface area, and increase degradation rate.

[0109] Furthermore, the content of polyurethane solid waste in the activated polyurethane is greater than or equal to 70%, which has the advantages of reducing costs and improving performance. When the content of polyurethane solid waste in the activated polyurethane is greater than or equal to 70%, it is paste-like or solid at room temperature, and the viscosity of the activated polyurethane (25°C) is greater than 30000mPa.s, which can be used to test that the content of polyurethane solid waste in the activated polyurethane is greater than or equal to 70%. Unless otherwise specified, the percentages in the present invention refer to weight ratios.

[0110] Furthermore, the activated polyurethane contains hydroxyl groups, and the hydroxyl value measured according to the ASTM E1899-2016 detection method is 5-400 mgKOH / g, 400-800 mgKOH / g, 800-1200 mgKOH / g or 1200-2000 mgKOH / g; further, the amine value measured according to the method of measuring the amine value by a potentiometric titrator is lower than 120 mgKOH / g. This indicates that the activated polyurethane contains an activated group, which is beneficial to improving the performance of the resin intermediate or the resin derivative; the low amine value has little effect on the reactivity of the resin.

[0111] Further, the viscosity (25°C) of the activated polyurethane is 3000-10000 mPa·s, 10000-20000 mPa·s, 20000-60000 mPa·s, 60000-200000 mPa·s, 200000-600000 mPa·s or 600000-1800000 mPa·s. High viscosity indicates high content of polyurethane solid waste, and increasing the content of polyurethane solid waste contained in the activated polyurethane reduces the cost.

[0112] Further, the peak value of the number average molecular weight Mn of the activated polyurethane measured by the two detectors RID and VWD (254nm) is distributed in 150-200; 200-350; 350-700; 700-1000, 700-1000, 1000-1800, 1800-3000, 3000-5000, 5000-10000, 10000-30000 or 30000-60000 g / mol; and according to the infrared spectrum test of GB / T 6040-2019, the activated polyurethane has a peak value of 1690 cm -1 -1780cm -1 There is an obvious infrared absorption peak in the wavenumber range, 1690cm -1 -1780cm -1 The ratio of the peak intensity in the wave number range to the peak intensity in the range of 1480-1570 is in the range of 1.5-1.2, 1.2-1.0, 1.0-0.95, 0.95-0.67, 0.67-0.66, 0.66-0.65 or 0.65-0.60, and the resin intermediate has a peak intensity of 1090-1210 cm -1 There is no obvious infrared absorption peak in the wavenumber range. The activated polyurethane with these characteristics has obvious carbamate functional groups, indicating that it contains initial polyurethane chain segments.

[0113] The activated polyurethane of the present invention is preferably prepared by a method involving internal mixing, which is a more preferred method compared to the prior art of screw shear extrusion. The latter method often causes problems such as material bridging, inability to enter bulk materials, and uneven mixing in the production of activated micropowders. The internal mixing method has the advantages of high density improvement efficiency, no bridging phenomenon, ability to enter bulk materials, and uniform mixing.

[0114] More preferably, the activated polyurethane of the present invention is prepared by adding an activator or a degradation agent for internal mixing. Compared with the traditional stirring and mixing reaction, it has the advantages of uniform mixing, high and low viscosity, especially high viscosity, high degradation efficiency, high amine removal efficiency, no bridging phenomenon, and the ability to feed large bulk materials.

[0115] Furthermore, the present invention claims protection for a resin intermediate obtained by any one of the above-mentioned methods for preparing the resin intermediate.

[0116] Preferably, the activated polyurethane or resin intermediate of the present invention is prepared by a method involving subjecting the mixed product to screw extrusion after mixing, which can solve the material bridging problem existing in screw extrusion and can be shaped or further degraded by screw extrusion.

[0117] Furthermore, the use of screw extrusion to activate the polyurethane or resin intermediate into a tubular continuous flow reactor or a vertical screw extruder can provide sufficient back pressure to allow the material to enter the next process.

[0118] Furthermore, the resin intermediate contains carbamate molecular fragments and hydroxyl groups. According to the ASTM E1899-2016 method, the hydroxyl value of the resin intermediate is 5-800 mg KOH / g.

[0119] Further, according to the method of measuring the amine value by a potentiometric titrator, the amine value of the resin intermediate is 0-20, 20-40, 40-80, 80-200 or 200-500 mg KOH / g. Furthermore, the amine value of the resin intermediate is 0-20, 20-40, 40-80 or 80-120 mg KOH / g. The alcoholysis technology commonly used in the prior art has a high reaction temperature, a long reaction time, and an amine value often greater than 120 mg KOH / g, which will have an adverse effect on the reactivity and performance of the resin. It is necessary to add acid or anhydride to the degradation agent to reduce the amine value, which increases the cost and reduces the degradation efficiency. The resin intermediate of the present invention contains an activating group, which is beneficial to improving the performance of the resin; the amine value is low, the reactivity of the resin intermediate is less affected, the performance is better, and the performance of the resin intermediate derivative obtained can be improved, and it can be achieved without using anhydride to remove the amine.

[0120] Furthermore, the resin intermediate does not contain the R1-NH-CO-R2 group. This can be tested according to the infrared spectrum of GB / T 6040-2019. The resin intermediate has a -1 -1780cm -1 There is an obvious infrared absorption peak in the wavenumber range, furthermore, 1690cm -1 -1780cm -1 The peak intensity in the wavenumber range is similar to that at 1480 cm -1 -1570cm -1 The peak intensity ratios in the range are 1.5-1.2, 1.2-1.0, 1.0-0.95, 0.95-0.67, 0.67-0.66, 0.66-0.65 or 0.65-0.60, and the resin intermediate is at 1090-1210 cm -1 There is no obvious infrared absorption peak within the wave number range; the content of polyurethane solid waste in the resin intermediate is greater than or equal to 70%, which has the advantages of reducing costs and improving performance. The content of polyurethane solid waste in the resin intermediate is greater than or equal to 70% by testing the viscosity of the resin intermediate polyurethane at room temperature (25°C)>30000mPa.s, or the resin intermediate is paste or solid.

[0121] Further, the viscosity (25° C.) of the resin intermediate is 10,000-20,000 mPa·s, 20,000-60,000 mPa·s, 60,000-200,000 mPa·s, 200,000-600,000 mPa·s or 600,000-1,800,000 mPa·s.

[0122] The preparation method of the resin intermediate provided by the present invention has a shorter reaction time than the alcoholysis method of the prior art, and the content of the initial polymer is higher. In addition, the distillation method commonly used in the prior art has the defect of high evaporation energy consumption. The method and equipment of the present invention are manufactured by banburying, which can increase the content of the initial polymer (polyurethane solid waste or activated polyurethane), reduce or even eliminate the distillation step, reduce the cost, and at the same time increase the degradation rate and reduce the amine value.

[0123] More preferably, the method of adding acid anhydride to the activated polyurethane or polyurethane waste for internal kneading of the present invention can further reduce the amine value. Compared with the traditional stirring mixing method which requires a low solid-liquid ratio and heating, it can achieve a low-temperature, high solid-liquid ratio deamine reaction, reduce side reactions, and reduce the amine value.

[0124] Furthermore, the present invention also provides a production system for the resin intermediate obtained by any one of the above methods, comprising a mixing device. Preferably, the mixing machine has a pressing component, which applies an additional squeezing force to the material in addition to the mixing roller during the mixing process to improve the mixing efficiency, and the pressing component applies the additional squeezing force to the mixing material through a combination of one or more effects of gravity, mechanical force, oil pressure, and air pressure.

[0125] Furthermore, the internal mixer is provided with a pressure control device, which includes a pressure relief valve, for controlling the pressure inside the internal mixer not to exceed a set safety value, thereby preventing safety accidents caused by excessive internal pressure. Preferably, the internal mixer is provided with a condensing device, for collecting and condensing the steam in the internal mixer and returning it to the internal mixer.

[0126] Furthermore, the production system also includes a screw extrusion device.

[0127] Furthermore, the present invention also provides a polyurethane composite material, comprising an activated polyurethane or a resin intermediate prepared by any one of the above methods, which has the advantages of high strength and toughness and can reduce costs.

[0128] Furthermore, the present invention also provides an epoxy resin, comprising an activated polyurethane or a resin intermediate prepared by any one of the above methods, which has the advantages of high strength and toughness and can reduce costs.

[0129] The present invention claims a method for producing a modified polymer as a resin intermediate, wherein the modified polymer is obtained by treating an initial polymer, the treatment comprising the following steps:

[0130] A: The initial polymer is subjected to a degradation reaction with a degradation agent having an active group, thereby breaking at least a portion of the molecular chain of the initial polymer and obtaining a resin intermediate containing molecular chain fragments of the initial polymer having an active group.

[0131] The initial polymer includes a thermoplastic polymer with a linear or branched molecular structure and a thermosetting polymer with a cross-linked network molecular structure, and the molecular weight of the initial polymer is not less than 10000 g / mol.

[0132] Further, the thermoplastic polymer includes polyethylene, polypropylene, polyolefin, polyvinyl chloride, polyester, polyamide or thermoplastic polyurethane, and the thermosetting polymer includes rubber, polyurethane, unsaturated polyester resin, epoxy resin, vinyl resin, acrylic resin or silicone resin. Preferably, the initial polymer molecular chain carries a chain-breaking group, and in step A, the molecular main chain of the initial polymer is disconnected from the chain-breaking group, and the chain-breaking group includes -N(H)n-, -NH-(CO)-O-, -C=C-, -C≡C-, -C≡CN-, -(CO)-, -(CO)-O-, -O-, -HN-(CO)-NH-, -(CO)-NH-, -NH-(CS)-O-, -CC=C-, -S-, -HN-CS-NH-, -CS-NH-, heterocyclic, cyclic, aromatic, hexyl, macrocyclic, polyhedral, isomer or polypeptide one or more combinations thereof. Preferably, the initial polymer molecule chain has a side group, the side group does not include a hydrogen atom, and the side group reacts synergistically with the degradation agent to help the initial polymer molecule break. The degradation reaction of the aforementioned step A includes one or more combinations of pyrolysis, hydrolysis, alcoholysis, aminolysis, acidolysis, alkaline hydrolysis, alcohol-alkali reaction, hydrogenolysis or acidolysis.

[0133] Preferably, the degradation reaction comprises the following reactions:

[0134] R1-A-(R2S)+R3-B-→R1-(A1)-R3-B1-+(R2S)-B2-

[0135] Wherein, -R1-A-(R2S)- is the initial polymer, A is the chain-breaking group, S is the side group, R3-B- is the degradation agent, and -B- is the active group of the degradation agent; R1-(A1)-R3-B1- and (R2S)-B2- are initial polymer molecular fragments formed after the initial polymer chain breaks, -A1- is the group formed after the degradation reaction of the chain-breaking group A, -B1- and -B2- are respectively active groups formed by the active end group B of the degradation agent at the two ends of the broken molecular chain, and the active groups A1 or B1 or B2 participate in subsequent reactions.

[0136] Preferably, the weight ratio of the initial polymer to the degradation agent is 1:0.1-0.4, 1:0.4-2, 1:2-5, 1:5-15.

[0137] In step A, the initial polymer includes a thermoplastic polyurethane TPU having a linear or branched molecular structure and / or a thermosetting polyurethane having a cross-linked network molecular structure; wherein the initial polymer molecular chain carries a chain-breaking group, and in step A, the initial polymer is reacted with a degradation agent to disconnect the molecular weight of the initial polymer from the chain-breaking group.

[0138] Furthermore, in step A, the initial polyurethane is mixed with the degradation agent to undergo a degradation reaction, thereby obtaining a resin intermediate containing molecular fragments and active groups of the initial polyurethane. Preferably, the initial polyurethane is subjected to a pulverization treatment, and the pulverization treatment includes but is not limited to a combination of one or more of the methods of crushing, shearing, grinding, ball milling, grinding, air flow pulverization, ultrasonic pulverization, etc.; the mixing method of the initial polyurethane and the degradation agent includes but is not limited to a combination of one or more of the methods of high-speed stirring, centrifugal stirring, kneading, mixing, screw extrusion, grinding, and ball milling;

[0139] Further, the chain-breaking groups include -N(H)n-, -NH-(CO)-O-, -HN-(CO)-NH-, One or more of; the degradation reaction includes alcoholysis; the degradation reaction may respectively include the following reactions:

[0140] Alcoholysis: PU+HO—R—OH to obtain a polyol mixture

[0141] Further, in step A, the initial polyurethane as the initial polymer is a polymer compound containing a chain-breaking group (AB), a main chain X, and a Y, and is prepared from an initial isocyanate XA a and initial polyol YB b The reaction generates; the degradation agent is MC c The active group C of the degradation agent reacts with the chain-breaking group (AB) to break the initial polyurethane molecules, forming a resin intermediate containing initial polymer molecular fragments with new active groups B and C. The degradation reaction is as follows (schematic diagram):

[0142]

[0143] Wherein, A is the isocyanate group in the initial polyurethane, B is the hydroxyl group in the initial polyurethane, (AB) is the carbamate group in the initial polyurethane; X is the initial isocyanate backbone; Y is the initial polyol backbone; M is the degradation agent backbone; C is the active group of the degradation agent, including hydroxyl, active hydrogen, amine or alkali metal group; a, b, c are functionalities respectively. The above is a typical degradation reaction mechanism, where a=2, b=3, c=1, and the degradation reactions of other a, b, c functional group combinations are similar and fall within the protection scope of the present invention.

[0144] Further, in step A, the degradation agent contains at least one active end group, and the active end group includes one or more of a hydroxyl group, an amide group, an acyl salt group, a urea group, an amine group, a carboxyl group, an anhydride group, a carboxylate group, an unsaturated double bond or triple bond, an ester group, a cyano group, a nitro group, a carbonyl group or an epoxy group.

[0145] Preferably, the initial polyurethane includes carbamate groups, the degradation agent includes hydroxyl groups, and in the degradation reaction the hydroxyl groups react with the carbamate groups and open at least a portion of the carbamate bonds to generate a resin intermediate containing initial polyurethane molecular fragments with active amino and hydroxyl groups.

[0146] As a typical example of the present invention, the initial polymer is polyurethane, the main chain of which contains carbamate groups, and the degradation reaction includes alcoholysis reaction; the active end group contained in the degradation agent is hydroxyl group, and in the degradation reaction, the hydroxyl group reacts with the chain-breaking group and opens at least a part of the urethane bond on the initial polymer molecular chain to generate a resin intermediate containing the initial polyurethane molecular fragment and the linear or branched molecular structure of the active group hydroxyl group. The degradation reaction includes the following reactions:

[0147] -R1NHCOOR2-+R3(OH)n→-R1NHCOOR3(OH) (n-1) -+-R2OH

[0148] Among them, -NHCOO- is a carbamate group; R3(OH)n is a degradation agent, and n is greater than 1; -R1NHCOOR3(OH)(n-1)- is a molecular chain fragment containing R1 and a carbamate group and an active group hydroxyl group in the initial polyurethane molecular chain, and -R2OH is a molecular chain fragment containing R2 and at least one active group hydroxyl group in the initial polyurethane molecular chain.

[0149] Furthermore, since the chemical structure of polyurethane contains urea chain -NHCONHR- in addition to carbamate chain -NHCOOR-, the following side reactions also occur during the degradation reaction:

[0150] Side reactions of urea groups:

[0151] -R1-NH-CONH-R1-+HO-R3-OH→-R1NHCOOR3OH+-R1NH2 At the same time, there are side reactions such as thermal degradation of carbamate and urea groups:

[0152] -R1-NH-CO-O-R2-→-RNCO+HOR2

[0153] -R1-NH-CO-O-(CH2)2-R2-→-R1NH2+CO2+CH2=CHR2

[0154] -R1-NH-CO-OO-R2-→-R1NHR2-+CO2

[0155] -R1-NH-CO-NH-R4-→-R1-NCO+R4NH2

[0156] The above side reactions will eventually generate compounds with hydroxyl or amine groups.

[0157] The above-mentioned side reactions will eventually generate compounds with hydroxyl or amine groups, which can make the grafting agent react with the amine-containing compound, so that there is no need to take the steps of separating and purifying the amine compound and the polyol for the resin intermediate.

[0158] Further, the degradation agent includes a polyol, and the polyol includes a diol and / or a high-functionality polyol. The diol includes a low molecular weight C2-C6 diol, preferably ethylene glycol, propylene glycol, 1,4-butanediol monoethylene glycol, propylene glycol or neopentyl glycol. The high-functionality polyol includes glycerol, trimethylolethane, pentaerythritol, sucrose polyol or sorbitol, and also includes various polyether polyols based on small molecule initiators, such as NJ-301, NJ-303, NJ-3063, NJ-430H, NJ-6305C, NJ-403, NJ-4110, NJ-330N, NJ-204, etc.

[0159] Preferably, the alcoholysis agent comprises one or a combination of diols and high-functionality polyols, and the weight ratio of diols to high-functionality polyester polyols is 1:0-0.3, 1:0.3-0.6, 1:0.6-1, 1:1-2, 1:2-4. If the ratio of diols is too high, more diols will remain in the product, making the post-treatment of the product difficult. At the same time, the alcoholysis product containing free diols is difficult to completely remove, resulting in problems such as too high hydroxyl value or difficulty in adjustment.

[0160] Preferably, the initial polymer is polyurethane waste, including refrigerator insulation rigid foam, cold storage insulation rigid foam, refrigerated truck and refrigerated container insulation rigid foam, building insulation rigid foam and other insulation rigid foam, sofa, seat, mattress soft foam, packaging cushion sponge, shoe sole, roller rubber, screen, conveyor belt, other elastomer, spandex or TPU products. The method for manufacturing modified polyurethane by the method of obtaining a resin intermediate through degradation reaction, the obtained resin intermediate can be used to manufacture polyurethane products, coatings, adhesives and other chemicals, including PU rigid foam, soft foam, elastomer, composite material, epoxy resin crosslinking agent, unsaturated resin, vinyl resin modifier and polyurethane rubber crosslinking agent.

[0161] Preferably, the weight ratio of polyurethane waste PU as the initial polymer to the degradation agent is 1:0.1-0.3, 1:0.3-0.5, 1:0.5-1, 1:1-2, 1:2-4, 1:4-8, 1:8-15. If the ratio of PU is too large, only a partial reaction will occur, and the density and viscosity of the product will also increase accordingly. If it is too small, the cost of removing the unreacted degradation agent will be too high.

[0162] Preferably, the temperature of the alcoholysis reaction is 110-150°C, 150-170°C, 170-180°C, 180-200°C, 200-220°C, 220-250°C. Too low a reaction temperature prolongs the reaction time. Although too high a reaction temperature is beneficial to increasing the alcoholysis reaction rate and shortening the reaction time, it increases the content of free amines in the final product; and makes the amine value or hydroxyl value of the final product too high.

[0163] The alcoholysis reaction time is 0.5h-64h, preferably, 0.5-2h, 2-3h, 3-6h, 6-12h, 12-24h, 24-48h, 48-64h,

[0164] Preferably, the yield of the alcoholysis reaction is 50-60%, 60-70%, 70-80%, 80-95%, 95-100%

[0165] Furthermore, the hydroxyl value of the resin intermediate obtained in step A is 10-50 mg KOH / g, 50-100 mg KOH / g, 100-180 mg KOH / g, 180-300 mg KOH / g, 300-500 mg KOH / g, 500-700 mg KOH / g, 700-1000 mg KOH / g.

[0166] Furthermore, the viscosity (25°C) of the resin intermediate obtained in step A is 50-200mPa·s, 200-500mPa·s, 500-1000mPa·s, 1000-2000mPa·s, 2000-10000mPa·s, 10000-20000mPa·s, 20000-60000mPa·s, 60000-200000mPa·s, 200000-600000mPa·s, 600000-1800000mPa·s.

[0167] Furthermore, the total amine value (KOH dosage) of the resin intermediate prepared in step A is 0-40 mg / g, 40-80 mg / g, 80-200 mg / g, 200-1000 mg / g.

[0168] On the other hand, the present invention claims a modified polymer as a resin intermediate prepared by any one of the above methods.

[0169] The present invention also provides a method for obtaining a modified polymer by subjecting a resin intermediate prepared by any of the above methods or a resin intermediate prepared by other methods to a grafting reaction treatment, wherein the modified polymer is obtained by treating an initial polymer, and the treatment comprises the following steps:

[0170] C: In step A, the degradation agent carries both active groups and chain extension groups, so that a grafting reaction is carried out simultaneously with the degradation reaction to obtain a modified polymer containing molecular fragments of the initial polymer and chain extension groups as a modified resin.

[0171] Further, the chain extension group is a functional group that can react with other groups or react with each other. Further, step C includes the following reaction:

[0172] R1-A-(R2S)+(R3C)-B-→R1-(A1C)-R3-B1-+(CR2S)-B2-

[0173] Wherein, -R1-A-(R2S)- is an initial polymer, A is a chain-breaking group, S is a side group, (R3C)-B- is a degradation agent having both an active group and a chain-extending group, -C- is a chain-extending group; -B- is an active group of the degradation agent; R1-(A1)-R3-B1- and (R2S)-B2- are initial polymer molecular fragments formed after the initial polymer chain is broken, -A1- is a group formed after the degradation reaction of the chain-breaking group A, -B1- and -B2- are respectively active groups formed by the active end group B of the degradation agent at the two ends of the broken molecular chain, and the initial polymer molecular fragments R1-(A1C)-R3-B1- and (CR2S)-B2- with the chain-extending group C can achieve molecular chain growth and / or cross-linking through the reaction of the chain-extending group C with other groups or the mutual reaction between the chain-extending groups C to obtain a modified polymer. On the other hand, the present invention can also provide a method for obtaining a modified polymer by grafting a resin intermediate prepared by any one of the above methods, wherein the modified polymer is obtained by treating an initial polymer, and the treatment comprises the following steps:

[0174] C: After step A, the obtained resin intermediate is subjected to a grafting reaction with a grafting agent having both a grafting group and a chain extending group to obtain a modified polymer as a modified resin containing molecular fragments of the initial polymer and a chain extending group.

[0175] Furthermore, the grafting group is a functional group that can react with the active end group in the resin intermediate, and the chain extension group is a functional group that can react with other groups or react with each other.

[0176] Further, the production of the modified polymer includes the following reactions:

[0177] R1-A-(R2S)+(R3)-B-→R1-(A1)-R3-B1-+(R2S)-B2-+(R4D)-C-→R1-(A1)-R3-(B1DR4)-C-+(R2S)-(B2DR4)-C-

[0178] Wherein, -R1-A-(R2S)- is the initial polymer, A is the chain-breaking group, S is the side group, R3-B- is the degradation agent, and -B- is the active group of the degradation agent; R1-(A1)-R3-B1- and (R2S)-B2- are initial polymer molecular fragments formed after the initial polymer chain breaks, -A1- is the group formed after the degradation reaction of the chain-breaking group A, -B1- and -B2- are respectively active groups formed by the active end group B of the degradation agent at the two ends of the broken molecular chain, and the active groups A1 or B1 or B2 participate in subsequent reactions.

[0179] (R4D)-C- is a grafting agent, and D is a grafting group, which is used to react with the active groups A1, B1, and B2 in the resin intermediate so that the initial polymer molecular fragments in the resin intermediate are connected to the grafting agent molecules with the chain extender C, so that these initial polymer molecular fragments can be reconnected through the chain growth and / or cross-linking reaction of the chain extender group C to obtain a modified polymer; C is a chain extender group, and D can be a side group or on the main chain, and can be connected to a direct grafting group or a chain extender group, or can not be connected to a grafting group or a chain extender group.

[0180] According to any of the above methods for obtaining a modified polymer resin by grafting reaction, the present invention further provides the following preferred embodiments.

[0181] Furthermore, the grafting reaction includes an esterification reaction, an acylation reaction or an ester exchange reaction.

[0182] Preferably, the esterification reaction can also be the esterification of acid derivatives with alcohols. The esterification of acid derivatives with alcohols mainly includes the reaction of alcohols with acyl chlorides, alcohols with acid anhydrides, alcohols with carboxylates, etc. The equation is as follows:

[0183]

[0184] R′OH+R″COCl→R″COOR′+HCl

[0185] R′X+R″COOM→R″COOR′+MX

[0186] Further, in step A, the initial polymer is polyurethane, including thermoplastic polyurethane TPU with a linear or branched molecular structure and thermosetting polyurethane with a cross-linked network molecular structure. The main molecular chain of the polyurethane contains carbamate groups, and the degradation agent contains hydroxyl groups. In the degradation reaction, the hydroxyl groups react with the carbamate groups and open at least a portion of the carbamate bonds on the initial polymer molecular chain to generate molecular chain fragments with a linear or branched molecular structure containing carbamate groups and / or hydroxyl groups.

[0187] Furthermore, the initial polymer molecular chain has chain-breaking groups, including -N(H)n-, -NH-(CO)-O-, -HN-(CO)-NH-, The degradation reaction includes alcoholysis; the degradation agent includes one or more combinations of polyols, acids, anhydrides, and carboxylates.

[0188] Furthermore, in step C, the grafting group includes a combination of one or more of an amide group, an amine group, a urea group, a hydroxyl group, a carboxyl group, and an acid anhydride, and the chain extension group includes a combination of one or more of an amide group, a urea group, an amine group, a hydroxyl group, a carboxyl group, a carboxylate group, an unsaturated double bond, and an ester group.

[0189] Preferably, in the esterification reaction of step A, the acid is a straight chain carboxylic acid, preferably the hydroxyl group is a primary hydroxyl group,

[0190] Furthermore, the esterification reaction in step A also includes a reaction between anhydride and alcohol, wherein the anhydride includes acetic anhydride, maleic anhydride,

[0191] Further, in step A, the initial polyurethane is Y(BA) (b-a) X(AB) a Y, composed of the initial isocyanate XA a and initial polyol YB b The reaction generates; the degradation agent is MC c ; The degradation reaction includes the following reactions:

[0192]

[0193] Further, in step C, the grafting agent is D d NE e ; The grafting reaction includes the following reactions:

[0194]

[0195] Wherein, A is the isocyanate group in the initial polyurethane, B is the hydroxyl group in the initial polyurethane, (AB) is the carbamate group in the initial polyurethane; X is the initial isocyanate main chain; Y is the initial polyol main chain; M is the main chain of the degradation agent; C is the active group of the degradation agent, including hydroxyl, active hydrogen, amine, and alkali metal groups; the chain-breaking group of the initial polyurethane is (AB); N is the main chain of the grafting agent, which can participate in the molecular morphology modification of the cured polyurethane resin; D is a grafting group, which can react with (AC) and B to generate (ACD) and (BD) so that the initial polymer molecular fragments in the resin intermediate are connected to the grafting agent molecules with the chain extender E; E is a chain extender group, which can reconnect the initial polymer molecular fragments through the chain growth and / or cross-linking reaction of the chain extender group E to obtain a modified polymer; a, b, c, d, and e are functional groups, respectively. The above is a typical degradation reaction mechanism, wherein a=2, b=3, c=1, d=1, e=1, and the degradation reactions of other a, b, c, d, e functional combinations are similar and fall within the protection scope of the present invention.

[0196] Further, in step A, the initial polymer contains -R1NHCOOR2- units; the degradation agent includes a compound R3(OH)n having a hydroxyl group; and the degradation reaction includes the following reaction:

[0197] -R1NHCOOR2-+R3(OH)n→-R1NHCOOR3(OH) (n-1) -+-R2OH

[0198] Further, in step C, the chain extension group of the grafting agent includes an unsaturated double bond, and the grafting group of the grafting agent includes a carboxyl group or an anhydride group; and the grafting reaction includes the following reaction:

[0199] -R1NHCOOR3(OH) (n-1) -+-R2OH+R4-(C=C) a -(CR5) b -(COOH)m→-R1NHCOOR3O-(CO)-(CR5) b -(C=C) a -R4+R2-O-(CO)-(CR5) b -(C=C) a -R4+H2O

[0200] or

[0201] -R1NHCOOR3(OH) (n-1) +-R2OH+-R4-(C=C) a -(CR5) b -(CO)O(CO)--R1NHCOOR3O-(CO)-(CR5) b -(C=C) a -R4-+-R2-O-(CO)-(CR5) b -(C=C) a -R4-

[0202] Wherein, -R2OH+R4-(C=C)a-(CR5)b-(COOH)m and R4-(C=C)a-(CR5)b-(CO)O(CO)- are grafting agents with grafting groups, and the grafting groups include carboxyl -(COOH)m or acid anhydride groups -(CO)O(CO)-. Preferably, a=1-6, which is the functionality of the unsaturated double bond functional group -(C=C)a- of the grafting agent. More preferably, b=0-6, which is the number of carbon atoms from the unsaturated double bond to the grafting group. -R4- and R5 are side groups of the grafting agent main chain, including H atoms, methyl groups and other organic groups. The grafting agent includes acrylates, methacrylates, acids with unsaturated double bonds, acid anhydrides or carboxylates.

[0203] Further, in step A, the initial polymer contains -R1NHCOOR2- units; the degradation agent includes an acid, anhydride or anhydride salt with an unsaturated double bond; and the degradation reaction includes the following reaction:

[0204] -R1NHCOOR2-+R4-(CC) a -(CR5) b-(COOH)m→R1-NH-(CO)-(CR5) b -(C=C) a -R4+R2-O-(CO)-(CR5) b -(C=C) a -R4+CC2

[0205] or

[0206] -R1NHCOOR2-+-R4-(C=C) a -(CR5) b -(CO)O(CO)-→-R1NH-(CO)-(CR5) b -(C=C) a -R4-+-R2-O-(CO)-(CR5) b -(C=C) a -R4-+CO2

[0207] Wherein, R4-(C=C)a-(CR5)b-(COOH)m and R4-(C=C)a-(CR5)b-(CO)O(CO)- are grafting agents with grafting groups, the grafting groups include carboxyl -(COOH)m or acid anhydride group -(CO)O(CO)-, a=1-6, which is the functionality of the unsaturated double bond functional group -(C=C)a- of the grafting agent, b=0-6, which is the number of carbon atoms from the unsaturated double bond to the grafting group, -R4- and R5 are side groups of the grafting agent main chain, including H atoms, methyl groups and other organic groups. The grafting agents include acrylates, maleic anhydride and esters, acids, anhydrides or carboxylates with unsaturated double bonds;

[0208] Further, in step C, when the initial polymer contains -R1NHCOOR2- units; the grafting agent includes an acid, anhydride or anhydride salt with an unsaturated double bond; the grafting reaction also includes an amide condensation reaction, including the following reaction:

[0209] -R-NH-R'+R4-(C=C) a -(CR5) b -(COOH)m→R-NR'-(CO)-(CR5) b -(C=C) a -R4 or

[0210] R-NH-R'+-R4-(C=C) a -(CR5) b -(CO)O(CO)-→R-NR'-(CO)-(CR5) b -(C=C) a -R4

[0211] Among them, R4-(C=C)a-(CR5)b-(COOH)m and R4-(C=C)a-(CR5)b-(CO)O(CO)- are grafting agents with grafting groups, and the grafting groups include carboxyl -(COOH)m or anhydride group -(CO)O(CO)-, a=1-6, which is the functionality of the unsaturated double bond functional group -(C=C)a- of the grafting agent, b=0-6, which is the number of carbon atoms from the unsaturated double bond to the grafting group, -RN-R' is an amine-containing compound, R is the main chain, and R' is a side group connected to the N atom, including H atoms, methyl groups and other organic groups. The grafting agent includes acrylate, maleic anhydride, esters with unsaturated double bonds, acids, anhydrides or carboxylates; the amide condensation reaction can make the grafting group react with hydroxyl and amine groups at the same time, so that the amino compound and polyol do not need to be separated and purified for the resin intermediate.

[0212] On the other hand, the present invention claims a modified polymer prepared by any of the above-mentioned methods through grafting reaction treatment.

[0213] The present invention also provides a method for preparing a modified polymer of a semi-cured material by mixing and treating the modified resin prepared by any of the above methods, wherein the modified polymer is obtained by treating the initial polymer, and the treatment comprises the following steps:

[0214] F: Add a curing agent to the modified polymer and mix them to obtain a semi-cured material.

[0215] Furthermore, the curing agent is a compound that can react with the chain extending group, or a compound that can induce the chain extending group to react with each other. Further, the reactive functional group of the compound that reacts includes one or a combination of free radical initiator, isocyanate group, acid anhydride, carboxyl group, epoxy group, amine group, amide group or aldehyde.

[0216] Furthermore, in step A, the initial polymer is polyurethane, including thermoplastic polyurethane TPU with a linear or branched molecular structure and thermosetting polyurethane with a cross-linked network molecular structure. The initial polymer molecular chain carries chain-breaking groups, including -N(H)n-, -NH-(CO)-O-, -HN-(CO)-NH-, The degradation reaction includes one or more combinations of alcoholysis, alkaline hydrolysis, hydrolysis, aminolysis, thermal decomposition or acidolysis; further, the degradation agent includes one or more combinations of polyols, alkaline solutions, water, ammonia water, acids, acid anhydrides, carboxylates, polar and non-polar solvents;

[0217] Preferably, in step C, the grafting group includes one or more combinations of amide groups, amine groups, urea groups, amine groups, hydroxyl groups, carboxyl groups, acid anhydrides, carboxylates or epoxy groups, and the chain extension group includes one or more combinations of amide groups, urea groups, amine groups, hydroxyl groups, carboxyl groups, unsaturated double bonds, ester groups, epoxy groups or aldehydes.

[0218] Preferably, in step C, the chain extending group comprises an unsaturated double bond.

[0219] Preferably, in step 1, the curing agent includes a thermosensitive curing agent, the thermosensitive curing agent includes a thermosensitive free radical initiator and a blocked isocyanate, and the thermosensitive free radical initiator includes a peroxide, a persulfide, a peroxycarbonate, a peroxyboric acid, an azo compound or other suitable free radical initiator that can initiate the curing of a double bond-containing compound.

[0220] More preferably, the free radical initiator includes tert-butyl peroxyisopropyl carbonate, methyl ethyl ketone peroxide, potassium persulfate, cumene hydroperoxide, dibenzoyl peroxide, tert-butyl perbenzoate or 2,4-di-tert-butyl peroxide isopropylbenzene.

[0221] Furthermore, in step 1, a step of heating the modified polymer is included, wherein the modified resin is heated to 50° C.-180° C., and then a curing agent is added, thereby reducing its viscosity and making the resin and the curing agent evenly mixed.

[0222] Furthermore, the method further comprises the step of:

[0223] G: The semi-cured material obtained in step 1 is heated to 50-160°C and impregnated with fibers and / or fillers to produce a reinforced or filled semi-cured material, wherein the fiber form includes one or a combination of fiber fabric, continuous fiber yarn, chopped fiber, ball fiber, powdered fiber, and filler. Filling the reinforcing material (i.e., fiber) and filler with the modified polymer under heating conditions can help improve the impregnation quality of the reinforcing material with the modified polymer. The process of impregnating the fiber and filler includes: one or a combination of high-speed stirring, centrifugal stirring, screw mixing, rubber roller kneading, stirring and kneading, forming a rubber film composite roll pressing, diluting and then impregnating, and composite and then rolling.

[0224] The non-reinforced semi-cured material can be used to make films for bonding plates, sheets, honeycombs, foams and other materials. The semi-cured material containing reinforcing or filling materials obtained in step G includes composite prepreg, sheet molding compound SMC, and bulk molding compound BMC. The manufacturing process method used can be selected from composite prepreg, sheet molding compound SMC, and bulk molding compound BMC manufacturing equipment and process, and reference can be made to "Composite Material Forming Technology and Application" (edited by Xu Zhu, National Defense Industry Press). The fiber materials used include metal fibers, non-metallic fibers, polymer fibers and natural fibers, including steel fibers, aluminum fibers, copper fibers, glass fibers, basalt fibers, ceramic fibers, alumina fibers, carbon fibers, polyester fibers, nylon fibers, polyvinyl alcohol fibers, ultra-high molecular weight polyethylene fibers, polypropylene fibers, spandex, bamboo fibers, hemp fibers, palm fibers, cotton fibers, and silk. Preferably, the weight ratio of fiber to modified resin is 0-0.1:1, 0.1-0.25:1, 0.25-0.4:1, 0.4-0.8:1, 0.8-1:1, 1.5:1, 1.5-2:1, 2-3:1, 3-4:1, 4-6:1, 6-8:1; the semi-cured material obtained in step g of the present invention can further enhance its mechanical properties, and can be used to manufacture composite materials according to traditional composite material semi-cured material molding processes and equipment, including prepreg composite material manufacturing processes, sheet molding compound composite material manufacturing processes, and bulk molding compound composite material manufacturing processes. In addition, molding processes including hand lay-up, injection, vacuum infusion, RTM, winding, pultrusion, compression molding, continuous plate, etc. can be used, and the molding pressure is 0.05-0.1MPa, 0.1-0.5MPa, 0.5-1MPa, 1-2MPa, 2-5MPa, 5-10MPa, 10-20MPa, 20-30MPa, 30-50MPa.

[0225] Furthermore, in step H or step G, a cooling step is included, wherein the semi-cured material is cooled to below 50° C. for storage, preferably, cooled to below 35° C. for storage.

[0226] On the other hand, the present invention claims a modified polymer prepared as a semi-cured material by any of the above-mentioned mixing methods.

[0227] As another embodiment, the present invention also provides a method for preparing a modified polymer of a cured resin by curing reaction treatment based on any one of the above methods and the modified resin or semi-cured material prepared, wherein the modified polymer is obtained by treating the initial polymer, and the treatment comprises the following steps:

[0228] Step e, impregnating the modified polymer into fibers at 0-150° C. to produce a composite material, wherein the fibers include one or a combination of fiber fabrics, continuous fiber yarns, chopped fibers, ball-shaped fibers, powdered fibers or fillers.

[0229] F: Add a curing agent to the composite material to carry out a curing reaction to obtain a cured resin.

[0230] Furthermore, the curing agent is a compound that can react with the chain extension group, or a compound that can trigger the chain extension group to react with each other. Furthermore, the curing agent molecule contains at least two or more chain extension group reaction functional groups to achieve the function of chain extension and curing of the modified polymer molecular chain. Chain extension group reaction functional groups include but are not limited to free radical initiators, isocyanate groups, acid anhydrides, carboxyl groups, epoxy groups, amine groups, and amide groups.

[0231] Furthermore, in step 1, the added curing agent also includes an accelerator compatible with the free radical initiator to promote the initiator to generate free radicals, and the accelerator includes a metal salt, an organic amine, including a cobalt salt, a copper salt, a zinc salt or an aniline accelerator. Adding an accelerator can reduce the initiation temperature of the initiator, improve the initiation efficiency of the initiator, and then achieve the curing of the modified resin at a low temperature or the rapid curing of the modified resin.

[0232] Preferably, in step 1, the curing agent includes a thermosensitive curing agent, the thermosensitive curing agent includes a thermosensitive free radical initiator and a blocked isocyanate, and the thermosensitive free radical initiator includes a peroxide, a persulfide, a peroxycarbonate, a peroxyboric acid, an azo compound or other suitable free radical initiator that can initiate the curing of a double bond-containing compound.

[0233] More preferably, the free radical initiator includes tert-butyl peroxyisopropyl carbonate, methyl ethyl ketone peroxide, potassium persulfate, cumene hydroperoxide, dibenzoyl peroxide, tert-butyl perbenzoate or 2,4-di-tert-butyl peroxide isopropylbenzene.

[0234] Furthermore, in step A, the initial polymer is a polyurethane, including thermoplastic polyurethane TPU with a linear or branched molecular structure and thermosetting polyurethane with a cross-linked network molecular structure. The main chain of the molecule contains a carbamate group, and the degradation agent contains a hydroxyl group. In the degradation reaction, the hydroxyl group reacts with the carbamate group and opens at least a portion of the carbamate bonds on the initial polymer molecular chain to generate a molecular chain fragment with a linear or branched molecular structure containing carbamate groups and / or hydroxyl groups. The initial polymer molecular chain carries a chain-breaking group, and the chain-breaking group includes -N(H)n-, -NH-(CO)-O-, -HN-(CO)-NH-, The degradation reaction includes one or more combinations of alcoholysis, alkaline hydrolysis, hydrolysis, aminolysis, thermal decomposition or acidolysis; the degradation agent includes one or more combinations of polyols, alkaline solutions, water, ammonia, acids, anhydrides, carboxylates, polar and non-polar solvents; preferably, in step C, the grafting group includes one or more combinations of amide groups, amine groups, urea groups, amine groups, hydroxyl groups, carboxyl groups, anhydrides, carboxylates or epoxy groups, and the chain extension group includes one or more combinations of amide groups, urea groups, amine groups, hydroxyl groups, carboxyl groups, unsaturated double bonds, ester groups, epoxy groups or aldehydes.

[0235] Preferably, in step A, the initial polymer is a polyurethane, the main molecular chain of which contains carbamate groups, and the degradation agent contains hydroxyl groups. In the degradation reaction, the hydroxyl groups react with the carbamate groups and open at least a portion of the carbamate bonds on the initial polymer molecular chain to generate molecular chain fragments with linear or branched molecular structures containing carbamate groups and / or hydroxyl groups.

[0236] Preferably, in step C, the chain extending group comprises an unsaturated double bond.

[0237] According to any of the above methods for obtaining a modified polymer resin by curing reaction, the present invention further provides the following preferred embodiments.

[0238] Further, the process of curing reaction is as follows:

[0239]

[0240] Further, the process of curing reaction is as follows:

[0241]

[0242] Among them, the grafting agent is D d NE e , A is the isocyanate group in the initial polyurethane, B is the hydroxyl group in the initial polyurethane, (AB) is the carbamate group in the initial polyurethane; X is the initial isocyanate main chain; Y is the initial polyol main chain; M is the degradation agent main chain; C is the active group of the degradation agent, including hydroxyl, active hydrogen, amine, and alkali metal groups; the chain-breaking group of the initial polyurethane is (AB); N is the main chain of the grafting agent, which can participate in the molecular morphology modification of the cured polyurethane resin; D is a grafting group, which can react with (AC) and B to generate (ACD) and (BD) so that the initial polymer molecular fragments in the resin intermediate are connected to the grafting agent molecules with the chain extender E; E is a chain extender group, which allows the initial polymer molecular fragments to be reconnected through the chain growth and / or cross-linking reaction of the chain extender group E to obtain a modified polymer; a, b, c, d, and e are functional groups, respectively.

[0243] As another embodiment, the process of the curing reaction is as follows:

[0244]

[0245] Among them, A is the isocyanate group in the initial polyurethane, B is the hydroxyl group in the initial polyurethane, (AB) is the carbamate group in the initial polyurethane; X is the initial isocyanate main chain; Y is the initial polyol main chain; M is the degradation agent main chain; C is the active group of the degradation agent, including hydroxyl, active hydrogen, amine, and alkali metal groups; Y(AB)(ba)X(AC)aM(a-c+1) is a carbamate polyol; Y(B)a is a recovered polyol; (AC) is the active end group generated by the active group of the degradation agent and one side of the carbamate group; D is a grafting group that can react with (AC) and B; E is a chain extension group that can extend or cross-link the polyurethane resin molecules to become a cured polyurethane resin; N is the main chain of the grafting agent, which can participate in the molecular morphology modification of the cured polyurethane resin; a, b, c, d, and e are functionalities, respectively.

[0246] Further, in step A, the following reaction is included:

[0247] -R1NHCOOR2-+R3(OH)n→-R1NHCOOR3(OH) (n-1) -+-R2OH Further, in step C, comprises the following reaction:

[0248] -R1NHCOOR3(OH) (n-1) -+-R2OH+R4-(C=C) a -(CR5) b -(COOH)m→-R1NHCOOR3O-(CO)-(CR5) b -(C=C) a -R4+R2-O-(CO)-(CR5) b -(C=C) a -R4+H2O

[0249] or

[0250] -R1NHCOOR3(OH) (n-1) -+-R2OH+-R4-(C=C) a -(CR5) b -(CO)O(CO)-→-R1NHCOOR3O-(CO)-(CR5) b -(C=C) a -R4-+-R2-O-(CO)-(CR5) b -(C=C) a -R4-

[0251] In step 1, the free radical initiator generates active free radicals to open the unsaturated double bonds to form free radicals to initiate a crosslinking curing reaction between the unsaturated double bonds.

[0252] Specifically, the following reactions are included:

[0253]

[0254] M1-OO-M2 is a peroxidation initiator, which generates free radicals under heating conditions or catalytic conditions of a promoter, and reacts with unsaturated double bonds to form chain growth points at the unsaturated double bonds.

[0255] In another embodiment, in step C, the initial polymer contains -R1NHCOOR2- units; the grafting agent includes esters, acids, anhydrides, and carboxylates with unsaturated double bonds; and the grafting reaction further includes an amide condensation reaction, including the following reaction:

[0256] -R-NH-R'+R4-(C=C) a -(CR5)b-(COOH)m→R-NR'-(CO)-(CR5) b -(C=C) a -R4 or

[0257] R-NH-R'+-R4-(C=C) a -(CR5) b -(CO)O(CO)-→R-NR'-(CO)-(CR5) b -(C=C) a -R4

[0258] Further, in step 1, the free radical initiator generates active free radicals to open the unsaturated double bonds to form free radicals to initiate a crosslinking and curing reaction between the unsaturated double bonds.

[0259] Specifically, the following reactions are included:

[0260]

[0261] M1-OO-M2 is a peroxidation initiator, which generates free radicals under heating conditions or catalytic conditions of a promoter, and reacts with unsaturated double bonds to form chain growth points at the unsaturated double bonds.

[0262] On the other hand, the present invention claims a modified polymer prepared by any of the above methods through a curing reaction treatment.

[0263] According to any one of the above methods for preparing a modified polymer, the present invention also provides the following preferred embodiments.

[0264] As a preferred embodiment, the resin intermediate, modified polymer, semi-cured material and cured resin do not contain isocyanate groups, so that the prepared resin intermediate, modified polymer, semi-cured material and cured resin can be stored for a long time and the toxicity of the product is reduced.

[0265] As a preferred embodiment, the curing agent does not contain a compound with an isocyanate group to prevent the semi-cured material from prematurely curing and hardening and the cured resin from foaming, thereby extending the process operation time. The production process operation time of the resin intermediate, the modified polymer, the semi-cured material and the cured resin is not less than 5 minutes, preferably, not less than 30 minutes, more preferably, not less than 2 hours, more preferably, not less than 4 hours, more preferably, not less than 8 hours, more preferably, not less than 12 hours, more preferably, not less than 24 hours.

[0266] As a preferred embodiment, the semi-cured material can be stored at 25°C for not less than 4 hours, preferably, not less than 24 hours, more preferably, not less than 3 days, more preferably, not less than 7 days, more preferably, not less than 21 days, more preferably, not less than 1 month, more preferably, not less than 2 months, more preferably, not less than 3 months, more preferably, not less than 6 months, more preferably, not less than 12 months.

[0267] As a preferred embodiment, step A further comprises the following steps:

[0268] B: removing and recovering the excess degradation agent in the resin intermediate obtained in step A. Further, the removal method includes a combination of one or more of vacuum distillation, thin film evaporation, extraction purification, fractionation, rectification, precipitation, etc. As a preferred embodiment, in step A, the degradation reaction includes alcoholysis reaction.

[0269] As a preferred embodiment, the degradation agent is an alcoholysis agent, and the alcoholysis agent includes a single molecule, an oligomer or a polymer with 1 to 6 hydroxyl groups.

[0270] As a preferred embodiment, the degradation agent is an alcoholysis agent which is a polyol with a functionality of 2-6 and a main chain containing 2-10 methylene groups.

[0271] As a preferred embodiment, the degradation agent is an alcoholysis agent which is a polyol with a functionality of 2-4, a main chain containing 2-6 methylene groups and an ether bond, which can improve the toughness of the polyurethane while maintaining its strength.

[0272] As a preferred embodiment, the degradation agent includes one or more selected from 1,2-propylene glycol, ethylene glycol, butanediol, pentanediol, hexanediol, diethylene glycol, 1,6-hexanediol, polyether polyols with a molecular weight of less than 700, or polyether polyols with a molecular weight of greater than 800. Preferably, the degradation agent is selected from ethylene glycol, diethylene glycol, dipropylene glycol, or glycerol, a polyol with a molecular weight of 200-700 and a functionality of 2-4, and a homogeneous resin intermediate can be obtained, and the resin intermediate does not need to be separated or purified, and can be used directly.

[0273] As a preferred embodiment, the active end groups in the resin intermediate include one or more of amide groups, urea groups, amine groups, hydroxyl groups, carboxyl groups, unsaturated double bonds, ester groups or epoxy groups.

[0274] As a preferred embodiment, the grafting agent contains unsaturated double bonds and compounds including but not limited to one or more of amide groups, amine groups, urea groups, amino groups, hydroxyl groups, carboxyl groups, acid anhydrides, and epoxy groups.

[0275] As a preferred embodiment, the free radical initiator includes but is not limited to peroxide initiator and its promoter. As a preferred embodiment, the initial polymer includes one or more cured polyurethanes, and the cured polyurethanes include polyurethane waste.

[0276] As another preferred embodiment, the resin intermediate is compounded from different polymer resin intermediates made from different initial polymers.

[0277] Preferably, the initial polymer accounts for no less than 20% of the resin intermediate, more preferably no less than 40%, more preferably no less than 60%, more preferably no less than 70%, more preferably no less than 80%, which can reduce costs and improve the elongation at break of the modified resin.

[0278] As a preferred embodiment, the number average molecular weight of the resin intermediate measured by RID and VWD (254nm) detectors is 150-200; 200-350; 350-700; 700-1000, 700-1000, 1000-1800, 1800-3000, 3000-5000, 5000-10000, 10000-30000, 30000-60000 g / mol.

[0279] As a preferred embodiment, the hydroxyl value of the modified resin is 0-50, 50-100, 100-200, 200-500, 500-800 mgKOH / g.

[0280] As a preferred embodiment, the acid value of the modified resin is: 0-8, 8-16, 16-30, 30-100, 100-200 mgkoH / g.

[0281] As a preferred embodiment, the amine value of the modified resin is 0-20, 20-40, 40-80, 80-150 mg KOH / g.

[0282] As a preferred embodiment, the amine value of the resin intermediate is 0-20, 20-40, 40-80, 80-200, 200-500 mg KOH / g

[0283] As a preferred embodiment, the resin intermediate or modified resin is measured by infrared spectrometer and has an absorption peak at 1680cm-1-1780cm-1 in the infrared spectrum, which can confirm that the resin intermediate or modified resin contains carbamate functional groups.

[0284] As a preferred embodiment, in the grafting reaction, the chain growth group of the grafting agent contains an unsaturated double bond, and the grafting group is one or more selected from amide, urea, hydroxyl, carboxyl, anhydride or epoxy. Because the unsaturated bonds can react with each other, no new polar groups will be introduced, and the initial polymer molecular chain will have little effect, and the adjustment of the modified polymer molecular chain is relatively easy to control. In addition, the unsaturated double bonds are initiated by an initiator, and the resin will not react at a temperature lower than the initiation temperature of the initiator, so that long-term storage and operation can be achieved. Once the initiation temperature of the initiator is reached, the resin can be quickly cured, and the curing efficiency of the resin can be improved.

[0285] As a preferred embodiment, in the grafting reaction, the grafting agent includes one or more selected from acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, phthalic acid mono-2-(acryloyloxy)ethyl ester, phthalic acid mono-2-(methacryloyloxy)ethyl ester, N-(carboxyphenyl)maleimide, N-(carboxyphenyl)methacrylamide, N-(carboxyphenyl)acrylamide or methacryloyl chloride. These grafting groups can effectively react with the active terminal hydroxyl groups on the resin intermediate.

[0286] As a preferred embodiment, in the degradation reaction, the total mass of the degradation agent is 0.5-10 times that of the initial polymer. The degradation agent in this range can achieve the reaction without causing too much workload for the subsequent vacuum distillation.

[0287] As a preferred embodiment, the total mass of the unsaturated carboxylic acid or unsaturated carboxylic anhydride as the grafting agent is 0.2-10 times that of the polymer resin intermediate, so that a higher reaction yield can be achieved.

[0288] As a preferred embodiment, when the grafting agent reacts with the resin intermediate, the ratio of the total carboxylic acid-carboxylic acid anhydride moles of the unsaturated carboxylic acid or unsaturated carboxylic acid anhydride as the grafting agent to the hydroxyl moles of the resin intermediate is 0.8-1.2. In this case, the unsaturated carboxylic acid and the hydroxyl groups in the resin intermediate react completely, and there is no need to remove the excess acid or anhydride or carboxylate by reduced pressure distillation, which can reduce the process steps.

[0289] As a preferred embodiment, the modified resin is blended with a reactive diluent having an unsaturated double bond or an unsaturated resin. The reactive diluent includes one or more of styrene, methacrylate, hydroxyacrylate, polyol or acrylate, and the unsaturated resin includes unsaturated polyester resin, acrylic resin, vinyl resin, etc., wherein representative substances include but are not limited to methyl methacrylate, isobornyl methacrylate, isooctyl acrylate, cyclohexane acrylate, decyl methacrylate, 2-ethylhexyl methacrylate, dihydrocyclopentadiene acrylate, ethoxylated phenoxyethyl acrylate, hydroxypropyl methacrylate, ethylene glycol diacrylate, propylene glycol dimethacrylate, neopentyl glycol dimethacrylate, 1.6-hexanediol diacrylate, cyclohexane dimethacrylate, diallyl phthalate, diethylene glycol dimethacrylate, tripropylene glycol diacrylate, hydroxybutyl acrylate, pentaerythritol tetraacrylate, pentaerythritol trimethacrylate, glycerol triacrylate, trimethylolpropane trimethacrylate, ethoxylated trimethylolpropane trimethacrylate or glycerol diacrylate, etc., which can adjust the viscosity and performance of the modified resin.

[0290] As a preferred embodiment, it can be used for preparing composite materials by various other composite material processes, including pultrusion, winding, infusion, hand lay-up, spraying, RTM, etc.

[0291] As a preferred embodiment, the semi-cured material can be stored at 25°C for not less than 4 hours, preferably, not less than 24 hours, more preferably, not less than 3 days, more preferably, not less than 7 days, more preferably, not less than 21 days, more preferably, not less than 1 month, more preferably, not less than 2 months, more preferably, not less than 3 months, more preferably, not less than 6 months, more preferably, not less than 12 months.

[0292] As a preferred embodiment, the curing agent for curing the modified resin includes a free radical initiator, and the free radical initiator includes but is not limited to a peroxide initiator and a promoter thereof. As a preferred embodiment, the initial polymer includes one or more cured polyurethanes. The cured polyurethane includes polyurethane waste, or, different resins made from different initial polymers are compounded to form a modified resin. Preferably, the initial polymer accounts for no less than 20% of the modified resin, more preferably no less than 40%. More preferably, no less than 60%, more preferably, no less than 70%, which can reduce costs and improve the elongation at break of the modified resin.

[0293] As a preferred embodiment, the initial polymer comprises one or more cured polyurethanes, and the cured polyurethanes comprise polyurethane waste.

[0294] As a preferred embodiment, the initial polymer resin has a wide range of sources. It can not only be prepared by direct solidification of black and white materials, but also can be taken from polyurethane waste, such as the commonly used insulation rigid foam in refrigerators and containers, polyurethane soft foam for mattresses and sofas, polyurethane elastomer screens for mines, polyurethane elastomer rollers, etc. The use of polyurethane waste not only reduces the cost of new polyurethane, but also increases the utilization value of polyurethane waste, which helps to improve the recycling level of polyurethane. The present invention is applied to the recycling of polyurethane, which can solve the key technical problems in the existing recycling of polyurethane. Because the existing polyurethane regeneration technology must make the initial polymer into standard chemical raw materials to make polyurethane that meets the performance requirements, it is necessary to adopt complex decomposition and purification steps, which are technically complex, energy-intensive, and cause by-product pollution. The present technology does not require these steps.

[0295] As a preferred embodiment, the tensile strength of the modified polymer is not less than 20 MPa, not less than 35 MPa, not less than 50 MPa, preferably, the tensile strength is not less than 60 MPa, and more preferably, the tensile strength is not less than 70 MPa.

[0296] As a preferred embodiment, the modified polymer has a flexural strength of not less than 30 MPa, not less than 45 MPa, preferably, not less than 55 MPa, more preferably, a flexural strength of not less than 65 MPa, more preferably, a flexural strength of not less than 75 MPa, more preferably, a flexural strength of not less than 85 MPa, more preferably, a flexural strength of not less than 95 MPa, more preferably, a flexural strength of not less than 105 MPa, more preferably, a flexural strength of not less than 120 MPa.

[0297] As a preferred embodiment, the elongation at break of the modified polymer is not less than 2%, preferably, the elongation at break is not less than 3%, more preferably, the elongation at break is not less than 4%, more preferably, the elongation at break is not less than 5%, more preferably, the elongation at break is not less than 20%, more preferably, the elongation at break is not less than 50%, more preferably, the elongation at break is not less than 100%, more preferably, the elongation at break is not less than 150%. On the other hand, the present invention claims a modified polymer resin prepared by any of the above methods.

[0298] Compared with the prior art, the technical solution mainly solves the following problems: 1) the polyurethane degradation process requires high temperature or the use of a large amount of chemical reagents, resulting in high energy consumption, high cost and possible secondary pollution; 2) the polyurethane degradation rate is slow, the efficiency is low, the energy consumption is high and it cannot meet the needs of large-scale treatment of polyurethane waste; 3) the polyurethane degradation product has a large number of aniline by-products, which is not conducive to subsequent resource utilization.

[0299] The beneficial effects of the technical solution are as follows: 1. Reduce costs: The present invention uses degraded polyurethane solid waste to mix with alcohol, and mixes at room temperature through an internal mixer, avoiding the problem of high temperature or the use of a large amount of chemical reagents in traditional methods, thereby reducing energy consumption and degradation costs. 2. Reduce environmental pollution and improve the safety of the production site: In the degradation process, the present invention uses alcohol as a reactant, without alcohol smoke and dust dispersion. Compared with the thermal degradation, chemical degradation, screw extrusion powder making and other methods in the prior art, it reduces the generation of harmful gases, waste liquids, flammable and harmful dust, and reduces environmental pollution. 3. Improve the degradation speed and efficiency, and meet the needs of large-scale treatment of polyurethane waste. 4. Controllable degradation products: The present invention can obtain degradation products with specific properties and uses by regulating the ratio of degraded polyurethane solid waste to alcohol, as well as the degradation conditions. The color is light and there are few aniline by-products, which is conducive to subsequent resource utilization.

[0300] Due to the advanced nature of the technical solution, it can be widely used in application fields such as waste utilization, polyurethane degradation and polyol preparation. First, the technical solution can effectively degrade polyurethane waste, reduce environmental pollution, and meet the needs of the waste utilization field. Secondly, the degradation process of the technical solution does not require high temperature, high pressure or the use of a large amount of chemical reagents, which reduces the degradation cost, avoids secondary pollution, and meets the needs of the polyurethane degradation technology field. Finally, the technical solution can obtain degradation products with specific properties and uses, such as polyols, etc., which meet the needs of the polyol preparation technology field. At the same time, due to the fast degradation speed and high efficiency of the technical solution, it can meet the needs of large-scale treatment of polyurethane waste. Therefore, the technical solution has broad market prospects and application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0301] The above content and the following specific embodiments of the present invention will be better understood when read in conjunction with the accompanying drawings. It should be noted that the accompanying drawings are only examples of the technical solutions claimed for protection.

[0302] Figure 1 It is a process flow chart of the present invention;

[0303] Figure 2 It is a schematic diagram of an internal mixer of the present invention;

[0304] Figure 3 is a side sectional view of the internal mixer of the present invention;

[0305] Figure 4 yes Figure 3 Schematic diagram of the internal mixing rotor in FIG.

[0306] Figure 5 It is a schematic diagram of the combination of the internal mixer and the screw extruder of the present invention.

[0307] The reference numerals are described as follows:

[0308] Nitrogen tube: 1

[0309] Cooling water pipe: 2

[0310] Mixing plate: 3

[0311] Mixing Chamber: 4

[0312] Mixing rotor: 5

[0313] Screw extruder: 6 DETAILED DESCRIPTION

[0314] The detailed features and advantages of the present invention are described in detail in the specific implementation modes below, and the contents are sufficient to enable any person skilled in the art to understand the technical contents of the present invention and implement them accordingly. Moreover, according to the description, claims and drawings disclosed in this specification, those skilled in the art can easily understand the relevant objects and advantages of the present invention.

[0315] It should be noted that in this specification, similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0316] In the description of this embodiment, it should be noted that the terms "upper", "lower", "inner", "bottom", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0317] To make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0318] This technical solution mainly adopts the following technical means:

[0319] On the one hand, the polyurethane solid waste (i.e., polyurethane waste) is mixed at -10°C-230°C using an internal mixer, preferably -10°C-230°C, more preferably, at 20°C to 200°C, more preferably, at 120°C to 200°C, more preferably, at 150°C-190°C, more preferably, at 170°C-190°C. Cooling measures can be taken during mixing to avoid temperature rise, the stirring speed of the internal mixer is 5-1000 rpm, preferably 100-1000 rpm, the mixing time is 1-30 minutes, preferably 1-10 minutes, more preferably 1-5 minutes, preferably, the internal mixer is provided with a pressing component, the pressing component applies an additional extrusion force to the material in addition to the internal mixing roller during the internal mixing process to improve the internal mixing efficiency, and the pressing component applies an additional extrusion force to the internal mixing material through a combination of one or more effects of gravity, mechanical force, oil pressure, and air pressure. The activated polyurethane with a small hydroxyl value or amine value is obtained. The preferred combination of temperature, rotation speed and mixing time can accelerate the mixing speed, destroy the micropore walls in the polyurethane solid waste, and increase the density of the activated polyurethane to accelerate the subsequent degradation speed. This method can also reduce the generation of aniline by-products. On the other hand, it can also produce activated polyurethane with a particle size greater than 40 meshes, avoid the generation of flammable and explosive dust with too small particles that fly into the air and endanger health, effectively reduce energy consumption, reduce costs, reduce environmental pollution, improve operator safety and improve degradation efficiency.

[0320] On the other hand, the polyurethane solid waste is mixed with an activator, wherein the activator includes but is not limited to diols, triols and polyols, including ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, glycerol, polyether polyol, wherein the ratio of solid waste to activator is 100:5-500, preferably 100:5-200, more preferably 100:10-100, and most preferably 100:15-45. The polyurethane solid waste is mixed with the activator under the condition of providing extrusion force and / or pressure to obtain an activated polyurethane with a certain hydroxyl value, preferably, the internal mixer is kept at -10°C-230°C for mixing, preferably -10°C-188°C, more preferably, at -10°C to 130°C, more preferably, at -10°C to 70°C, more preferably, at -10°C-35°C, more preferably, at 10°C-35°C. Preferably, the internal mixer is provided with a pressing component, which applies an additional squeezing force to the material in addition to the internal mixer roller during the internal mixer process to improve the internal mixer efficiency. The pressing component applies an additional squeezing force to the internal mixer material through a combination of one or more effects of gravity, mechanical force, oil pressure, and air pressure. Preferably, the internal mixer is provided with a pressure control device and a condensing device. The pressure control device includes a pressure relief valve for controlling the pressure in the internal mixer not to exceed a set safety value. The condensing device is used to collect and condense the steam in the internal mixer and return it to the internal mixer. Mixing is carried out in a closed internal mixer, and the internal mixer adopts a lower temperature at the same time, which can avoid the evaporation of the activator during mixing, maintain the stability of the ratio of the activator to the polyurethane solid waste, and avoid the generation of excessive aniline by-products caused by excessive temperature; cooling measures can be taken during mixing to avoid temperature rise, and a condensing reflux device can be connected to the internal mixer to condense and reflux the steam generated during mixing into the internal mixer to avoid the ratio of the polyurethane solid waste and the activator from being unstable due to the volatilization of steam. In addition, the activation step of the polyurethane solid waste and the activator in the internal mixer is also used as a preliminary degradation reaction, which further improves the efficiency of the subsequent degradation reaction. The stirring speed of the internal mixer is 5-1000 revolutions, preferably 100-1000 revolutions, and the mixing time is 1-30 minutes, preferably 1-10 minutes, and more preferably 1-5 minutes, to obtain activated polyurethane. If the stirring speed is low, the mixing time required will be long, and the aniline by-products produced will also be less, and vice versa. Since a large amount of heat is generated during the internal mixing process, uncontrollable side reactions are easily generated. The present invention further adopts the mixing step of mixing the activator with the polyurethane solid waste. The heat generated during the internal mixing process is absorbed by the activator, which can reduce side reactions, and enable the activator to utilize the energy of the internal mixing to react with the polyurethane solid waste to cause a certain degree of degradation, and can also reduce the phenomenon of dust flying during the production process.

[0321] Optionally, the activated polyurethane or polyurethane solid waste is added to a screw extruder for extrusion, shaping or further degradation to form materials in shapes including but not limited to paste, flocculent, slag, granular, strip, sheet, block, etc., with a density of 0.1-0.3 g / cm 3 , 0.3-0.5g / cm 3 , 0.5-0.8g / cm 3 , 0.8-1.1g / cm 3 , the particle size is greater than 40 meshes, reducing the phenomenon of dust flying during the production process. The extrusion section temperature of the extruder is 20-80°C, 80-160°C, 160-230°C. Optionally, during extrusion, the die head can be eliminated, so that the screw extruder only plays the role of extruding and shaping the activated polyurethane or polyurethane solid waste. The screw extruder is a single-screw or twin-screw extruder, preferably a twin-screw extruder, more preferably, a double-wrist or double-cone double-wrist extrusion device is used to assist in feeding to prevent material bridging and accumulation.

[0322] Optionally, the activated polyurethane is stored in a vacuum package or flushed with nitrogen to prevent moisture absorption. This method can effectively prevent dust from flying, reduce energy consumption, reduce costs, reduce environmental pollution, improve operator safety and improve degradation efficiency.

[0323] Preferably, the activated polyurethane is continuously extruded into a mixing and degradation device through the back pressure of a screw extruder for further mixing and degradation. The mixing method includes but is not limited to a combination of one or more of high-speed stirring, centrifugal stirring, kneading, mixing, screw extrusion, grinding, and ball milling. The mixing includes but is not limited to banburying and open mixing, the screw extrusion includes single screw, twin screw and multi-screw extrusion, and the screw extrusion includes horizontal screw extrusion, vertical screw extrusion and oblique screw extrusion; preferably, the degradation reaction adopts banburying equipment or screw extrusion or active pipeline continuous flow reactor, which can realize the mixed degradation of high viscosity or solid activated polyurethane; more preferably, the degradation reaction continues to squeeze the activated polyurethane into the vertical screw extrusion equipment or the active pipeline continuous flow reactor with a multi-layer rotatable turntable through the back pressure of the screw extruder, because the vertical screw equipment and the active pipeline continuous flow reactor are both tubular equipment, which can realize efficient extrusion, shearing and mixing of materials, and at the same time, the material temperature can be accurately controlled while bearing pressure and controlling the pressure in the equipment, so that the reaction efficiency can be improved, the reaction time can be shortened, and the reaction safety risk can be reduced. On the other hand, the banburying product formed by the aforementioned banburying is preferably mixed with the degradation agent as the activated polyurethane and heated and stirred at 180-230°C for 5-120 minutes for degradation reaction to obtain a resin intermediate. Preferably, the degradation agent is a polyol, and the activated polyurethane is mixed with the polyol to form a slurry, and the activated polyurethane: polyol = 100: 0-400, preferably 100: 0-200, and more preferably 100: 0-100. The reaction time is 1-120 minutes, preferably 1-30 minutes, and more preferably 1-10 minutes. Because most of the micropore walls of the polyurethane solid waste in the activated polyurethane have been destroyed, the degradation agent can easily penetrate into the polyurethane solid waste, so this method can effectively increase the degradation rate and increase the degradation efficiency, and at the same time obtain a resin intermediate with specific properties and uses. Preferably, the activated polyurethane produced by the banburying method in the aforementioned activation step is then mixed with the degradation agent. As another embodiment, the polyurethane waste continues to undergo a mixing and degradation reaction with a newly added degradation agent while producing activated polyurethane in an internal mixer, or the polyurethane waste continues to undergo a mixing and degradation reaction with the activator as a degradation agent while producing activated polyurethane in an internal mixer, thereby achieving a degradation reaction of the activated polyurethane, which can achieve better degradation efficiency and lower production of aniline by-products.

[0324] Optionally, after the activation reaction or degradation reaction is completed, an anhydride deamine agent is added to the reaction product for mixing to carry out a deamine reaction. The deamine reaction temperature is 20-230°C, preferably 20-150°C, more preferably 20-70°C, the ratio of anhydride to the reaction product is 1-100:100, preferably 1-50:100, more preferably 1-20:100, preferably, a mixing method including but not limited to internal mixing or open mixing is used to mix the activated polyurethane and the deamine agent, more preferably, a internal mixing method is used to mix the activated polyurethane and the deamine agent, or, during the activation reaction or degradation reaction, the anhydride deamine agent is injected into a internal mixer for a deamine reaction. The deamine reaction can be completed under low temperature and high viscosity of the activated polyurethane or resin intermediate, with less by-products, and the reaction is carried out in a closed cavity to avoid being affected by moisture in the air or steam escaping. This cannot be achieved by traditional stirring methods, because acid anhydrides are often solid at room temperature. If the mixing reaction is carried out according to the traditional stirring method, if the viscosity of the activated polyurethane or resin intermediate is high, it cannot be mixed evenly with the acid anhydride deamine agent, and the reaction cannot be complete. If the temperature is increased to reduce the viscosity, it will cause side reactions such as esterification reactions, consume acid anhydrides, and reduce the deamine effect. Finally, the performance of the activated polyurethane or resin intermediate is tested, including parameters such as hydroxyl value and amine value, to ensure that it meets the subsequent resource utilization requirements. The combined use of the above three technical means can effectively solve the problems existing in the polyurethane degradation process in the prior art.

[0325] instrument

[0326] Internal mixer: Guangdong Changfeng Technology Co., Ltd. CF-1L internal mixer; Shanghai Peltz screw kneading machine

[0327] Extruder: Guangdong Changfeng Technology Co., Ltd. CF-45 double-wrist single-screw granulator; experimental double-cone twin-screw granulator

[0328] Degradation reactor: four-necked flask; active microreactor (model: FluDynam-ST-R-500HC, manufactured by Runshi Microfluidics Technology (Jiangsu) Co., Ltd.)

[0329] Amine removal reactor: four-necked flask; CF-1L internal mixer produced by Guangdong Changfeng Technology Co., Ltd.

[0330] Test Case

[0331] The test methods for the amine value used in the present invention are all: the amine value is measured by a potentiometric titrator.

[0332] The amine value is the value of the acid required to neutralize one gram of alkaline amine expressed in milligrams of potassium hydroxide. The amine value is often used to represent the functionality of polyols. This experiment uses the perchloric acid glacial acetic acid titration method, which is automatically titrated by a potentiometric titrator and the amine value of the sample is calculated after the analysis is completed.

[0333] 1. Prepare reagents and instruments

[0334] Sample: Hydroxyl-containing compound (i.e., degradation product of polyurethane)

[0335] Titrant: 0.1mol / L perchloric acid glacial acetic acid standard solution

[0336] Solvent: Glacial acetic acid and acetonitrile

[0337] Instruments: Ray magnetic potentiometric titrator (model ZDJ-4B), titration stirring table, non-aqueous electrode (filling liquid is ethanol saturated lithium chloride), 4.100mL titration cup, electronic balance (accurate to 0.1mg), beaker, measuring cylinder, volumetric flask, etc.

[0338] 2. Determination method

[0339] Weigh about 0.2 g of sample, dissolve it in 20 mL of glacial acetic acid, then add 20 mL of acetonitrile to dilute it. After stirring until the sample is dissolved, move it into the titration cup and place it on the titration table. Set the instrument titration method according to the following parameters, and use 0.1 mol / L standard perchloric acid-acetic acid solution for titration analysis. Get the results after the analysis is completed.

[0340] The titrator instrument parameters are as follows:

[0341] End point mode: differential determination;

[0342] End point judgment volume: 5 before; 0.3 after;

[0343] Minimum drop volume: 10uL;

[0344] Maximum drop volume: 1000uL;

[0345] End point judgment differential value: 200;

[0346] Pre-titration: No;

[0347] Stirring speed: 200;

[0348] Interval between each drop: 2000m / s;

[0349] Result calculation formula: Amine value = C*V*56.11 / m

[0350] In the formula: V is the volume at the titration endpoint (ml); C is the concentration of the perchloric acid / glacial acetic acid standard solution (mol / L); m is the sample amount (g); 56.11 is the molar mass of potassium hydroxide (g / mol).

[0351] Raw materials list:

[0352] Ethylene glycol Commercially available Diethylene glycol Commercially available Triethylene glycol Commercially available Hexanediol Commercially available PEG400 Commercially available NJ210 Jurong Ningwu New Materials Co., Ltd. STEPANPOL PS-1752 STEPAN COMPANY LLC 1,9-Nonanediol: Jurong Ningwu New Materials Co., Ltd. Butanediol Commercially available Neopentyl glycol Commercially available glycerin Commercially available NJ303 Jurong Ningwu New Materials Co., Ltd. Sorbitol NJ-6305C Jurong Ningwu New Materials Co., Ltd. Sucrose polyol NJ-4110 Jurong Ningwu New Materials Co., Ltd. Potassium Titanate Commercially available Potassium acetate Commercially available Potassium hydroxide Commercially available 3-Methyl-1,5-pentanediol Commercially available

[0353] The present invention Figure 1 The production system of activated polyurethane and resin intermediates is shown, and the system includes a mixing system and a reaction system. The mixing unit includes a crushing unit and / or an extrusion unit, and the crushing unit includes but is not limited to an internal mixer; the extrusion unit includes but is not limited to a screw extruder, and the polyurethane industrial solid waste is delivered to the production system by the feeding unit as the initial polymer. The feeding unit includes but is not limited to a double-wrist feeding device and a double-cone feeding device, and the extrusion unit includes but is not limited to a single screw extruder and a twin-screw extruder. Chemical reactions such as degradation are carried out in the reaction unit, and the reaction unit includes but is not limited to a continuous flow reactor, a microchannel reactor, a vertical screw extruder, a vertical screw reactor and a stirring reactor. As a specific experiment, the present invention adopts an active microreactor as the reaction unit (model FluDynam-ST-R-500HC, manufactured by Runzhi Microfluidics Technology (Jiangsu) Co., Ltd.).

[0354] Figure 2-4 The figure shows the internal mixer used in the present invention. The internal mixer is connected to a nitrogen pipe 1 and a cooling water pipe 2. There is an internal mixer 4. There is a pair of internal mixer rotors 5 in the internal mixer 4. The relative rotation of the rotors is used to extrude the materials, thereby generating an extrusion force on the materials to help the materials mix evenly. After the mixing is completed, the internal mixer 4 is turned over, and the rotors are reversed to pour out the materials. The upper part of the internal mixer chamber has an internal mixer pressing plate 3 as a clamping component. The clamping component is driven by the cylinder to seal the internal mixer 4, and can apply additional extrusion force to the internal mixer materials, so that friction is generated between the materials, and the internal mixer efficiency is improved. After the internal mixer is completed, the upper clamping component is driven by air pressure to open, and the internal mixer 4 can be turned over to discharge the materials. A pressure control device including an exhaust port and a pressure control valve can be opened on the internal mixer 4. When the internal mixer produces gas or steam, the gas or steam can be discharged through the pressure control device when the set pressure is reached to prevent the internal mixer 4 from overpressure and danger. The exhaust port of the pressure control device can be connected to a condensing device, and the high-temperature steam can be condensed by the condensing device and reflux into the mixing chamber 4 to keep the mixing ratio of the mixing material stable; when the mixing material needs to be cooled, the cooling water channel connected by the cold water pipe 2 is used to cool the rotor, take away the heat generated by the mixing and achieve the cooling effect.

[0355] like Figure 5The figure shows a combination of an internal mixer and a screw extruder, wherein a screw of a screw extruder 6 is provided at the lower part of an internal mixing chamber 4. During internal mixing, the screw reverses and cooperates with the internal mixing rotor 5 to make the material return to help the internal mixing of the material. During discharge, the screw rotates forward and cooperates with the internal mixing rotor 5 to extrude the internal mixing material from the lower part of the internal mixing chamber 4.

[0356] As an example, the screw extruder used in the present invention is a single-screw extruder, which has a feeding device and a screw extruder. Although the mixing effect of the single-screw extruder is not as good as that of the twin-screw extruder, it has better conveying capacity and can generate a larger conveying back pressure.

[0357] As an example, in order to prevent material bridging and causing feeding problems, the feeding unit of the present invention adopts a double-wrist feeding device or a double-cone feeding device. Both the double-wrist feeding device and the double-cone feeding device can press the material into the screw extruder. It can be found in the experiment that directly feeding the material is easy to bridge, causing insufficient feeding of the screw extruder and reducing production efficiency, while the feeder using either of the two can achieve smooth feeding without material bridging.

[0358] As an example, the screw extruder used in the present invention is a twin-screw extruder, and the twin-screw extruder adopts a double-cone double-wrist feeding device.

[0359] The activated polyurethane, resin intermediate and low amine value compound of this patent are prepared according to the following steps:

[0360] (1) Take 500 g of polyurethane solid waste, mix it with the activator in an internal mixer according to the ratio in Table 1, start the internal mixer for internal mixing, and after the internal mixing is completed, the internal mixing product can be used as activated polyurethane. The internal mixer is set with corresponding operating parameters according to Table 2. After the internal mixing is completed, the internal mixing product obtained is activated polyurethane.

[0361] Table 1: Parameters of mixing ratio of polyurethane solid waste and activator

[0362]

[0363]

[0364] Table 2 Internal mixer operating parameters and detection parameters of activated polyurethane of internal mixer product

[0365]

[0366]

[0367]

[0368] By comparison, it can be found that compared with Examples 1 and 2 using banburying, the product can measure the hydroxyl value and amine value, indicating the presence of activated groups hydroxyl and amine groups, and at the same time, the density has increased, indicating that the micropore wall is destroyed. Compared with Examples 3-9 using banburying with an activator, Examples 1 and 2 have lower banburying temperatures, fewer aniline byproducts, and the time for banburying completion of Examples 6-9 has also been shortened, with a higher density. Even the banburying product of Example 9 is in a liquefied form, i.e., activation and degradation are carried out simultaneously, and the activator is also used as a degradation agent to carry out degradation reaction during the banburying activation process, so the product obtained after banburying is a degradation reaction product. It is shown that the banburying step is crucial to improving the efficiency and reducing side reactions in the preparation of activated polyurethane. Furthermore, the internal mixer used in this embodiment has a movable upper pressing block, which compresses the material and seals the internal mixing chamber through the vertical column and air pressure drive during the internal mixing process. During the internal mixing process, the upper pressing block always applies pressure to the material. Due to the driving of air pressure, when the density of the material increases and the volume decreases, the upper pressing block will fall under the driving of air pressure, and still compress the material, thereby achieving the effect of destroying the microporous structure and increasing the density. When the upper pressing block is not pressed in place and only plays a sealing role, although the material is double-rolled in the sealed chamber, the material is fluffy. At this time, the same internal mixing effect cannot be achieved even if the internal mixing time is extended by 1 times. Therefore, for such low-density fluffy materials, the double-roll mixing must apply additional pressure to the internal mixing material through the pressing component in the internal mixer to achieve the purpose of improving the internal mixing efficiency. At the same time, the upper pressing block has a limiting structure to prevent the upper pressing block from excessively pressing down and causing the liquefied material to overflow. .

[0369] (2) The kneaded product is put into a screw extruder as activated polyurethane or activated polyurethane solid waste, and the operating parameters of the screw extruder are set according to Table 3. The extruded product is activated polyurethane, and the detection characteristics of the extruded product are shown in Table 4.

[0370] Table 3: Screw extruder operating parameters

[0371]

[0372]

[0373] Table 4 Extrusion product testing parameters

[0374]

[0375]

[0376] As you can see,

[0377] The polyurethane solid waste powder processed directly by an extruder for a long time has a small particle size, flying dust, flammable and explosive risks, easy to absorb moisture, and also because of the high processing temperature and long processing time, the powder has discoloration and there are by-products. The above disadvantages can be avoided by using the method of other embodiments.

[0378] (3) 500 g of the extruded product was taken as activated polyurethane. Comparative Example 1-2: 500 g of the polyurethane sofa soft foam solid waste was taken as activated polyurethane, and the activated polyurethane was mixed with a degradation agent to form a slurry. The mixture was mixed according to Table 5, and a degradation reaction was carried out to produce a resin intermediate.

[0379] Table 5: Parameters of mixing activated polyurethane and degradation agent

[0380]

[0381] (4) The activated polyurethane and the polyol degradation agent were stirred and mixed in a four-necked flask under nitrogen protection and reflux to perform a degradation reaction, and the reaction pressure was normal pressure. Specifically, the degradation reaction parameters are shown in Table 6.

[0382] Table 6: Degradation reaction parameters

[0383]

[0384] The detection performance of degradation reaction products is shown in Table 7.

[0385] Table 7: Degradation reaction product detection performance table

[0386]

[0387]

[0388] It can be seen that compared with comparative examples 1 and 2, under the same solid-liquid ratio, the degradation time of examples 1-9 is shortened, and the amine value is lower, indicating that after the crushing step, especially after the mixing step of banburying or screw extrusion, the density of the polyurethane solid waste increases, the mixing efficiency is improved, thereby improving the degradation efficiency, and reducing the generation of by-products in aniline. Further, in Example 9, an activator is added to the crushing step, and the activator also acts as a degradation agent, so that the crushing step and the degradation step are completed at one time in the banburying, which greatly shortens the degradation time. It should be noted that in this embodiment, the upper pressing block of the banbury mixer is no longer pressed down after the material is melted. At the same time, an exhaust port is opened on the banbury mixer, which is connected to the condenser pipe. The exhaust pipe is equipped with a pressure control valve, and the control valve controls the positive pressure inside the mixing chamber to not exceed 1 bar. When the gas generated during the banburying process is greater than 1 bar, it is discharged from the exhaust valve into the condenser pipe, and the steam therein is collected by the condenser pipe and returned to the banburying chamber. Further, there is a protective device around the banburying chamber to prevent the high-temperature material in the banburying chamber from splashing and injuring people.

[0389] At the same time, it can be seen from the comparison of Examples 1-2 that the activated polyurethane extruded by the screw machine takes less time to degrade and has a lower amine value than the activated polyurethane not extruded, indicating that there are fewer by-products. The other reasons are the same as above.

[0390] (5) Mixing the amine remover with the degradation reaction product (i.e., the resin intermediate) in a ratio of 1:35:45:10. The amine remover comprises a composition of succinic anhydride, maleic anhydride, phthalic anhydride, and methyltetrahydrophthalic anhydride. The proportion of each component added is succinic anhydride: maleic anhydride: phthalic anhydride: methyltetrahydrophthalic anhydride = 10:35:45:10.

[0391] (6) After the deamine agent and the degradation reaction product are mixed in proportion, they are injected into a four-necked flask or an internal mixer for deamine reaction, and the deamine agent is an acid anhydride. The ratio of the acid anhydride to the degradation reaction product is 1-50:100, preferably 1-20:100, and more preferably 1-30:100. Preferably, the deamine reaction is carried out in an internal mixer. The deamine reaction temperature is 20-100°C, preferably 20-70°C. The deamine reaction time is 1-120 minutes, preferably 1-30 minutes, and more preferably 1-10 minutes. Specifically, the deamine reaction parameters are shown in Table 8.

[0392] Table 8: Amine removal reaction parameters

[0393]

[0394]

[0395]

[0396] The detection performance of the obtained amine removal reaction product, i.e., the low amine value resin intermediate, is shown in Table 9-1 and Table 9-2.

[0397] Table 9-1: Detection performance table of amine removal reaction products

[0398] Example Amine value (mgKOH / g) Example A1 51 Example A2 65 Example A3 50 Example A4 35 Example A5 32 Example A6 65 Example A7 Example A8 40 Embodiment A9 34 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Comparative Example 8 Example 1 55 Example 2 65 Example 3 71 Example 4 55 Example 5 45 Example 6 39 Example 7 34 Example 8 25 Example 9 41

[0399] Table 9-2: Technical Effects of Examples and Comparative Examples

[0400]

[0401]

[0402]

[0403]

[0404] The degradation reaction product with high viscosity (viscosity greater than 30000mPa.s) is not convenient to be mixed and reacted with a four-necked flask at low temperature. Increasing the temperature can reduce the viscosity, but the amine removal effect is not good. According to Tables 7-9, it can be seen that the amine value of the product of each embodiment and comparative example is reduced to a certain extent by using the amine removal method of the present invention. Compared with comparative examples 1 and 2, it can be seen that the reaction temperature of the present invention is low. At relatively low temperatures, high-viscosity activated polyurethane and amine removal agent are mixed in a banbury mixer, and then a better amine removal effect can be obtained, and the amine value of the obtained product is lower. It can be seen from comparative examples 1 and 2 that if the existing technology of stirring and mixing is used, heating must be required to reduce the viscosity and mix the acid anhydride evenly, so that the amine removal effect is reduced.

[0405] At the same time, by comparing A1-11 and Comparative Examples 1-8, it was found that:

[0406] Example A1 has mixing and extrusion. Compared with Comparative Example 1, the density of activated polyurethane is increased and the degradation time is shortened; compared with Comparative Example 3, the yield is high and dust-free. Compared with Comparative Example 5, it is not easy to form bridges, extrusion is smooth, and high-density activated polyurethane is obtained at one time;

[0407] Example A2 has internal mixing but no extrusion, and removes amine at low temperature. Compared with Comparative Example 2, the density of activated polyurethane is increased, and the degradation time is short; compared with Comparative Example 4, the yield is high, there is no dust,

[0408] The solid waste content of the activated polyurethanes prepared in Examples A3-A9 is up to 70%.

[0409] Example A3 uses polyurethane solid waste and activator to extrude at low temperature. Compared with comparative example 5, the color is lighter and it is not easy to bridge.

[0410] Example A4 uses polyurethane solid waste plus an activator to perform low-temperature warm mixing and high-temperature extrusion degradation and then remove amines, which can achieve the removal of amines from resin intermediates with low amine values.

[0411] Example A5 uses polyurethane solid waste and activator to perform high-temperature kneading and degradation and then remove amines, which can achieve the removal of amines from high-viscosity resin intermediates.

[0412] Comparison of Example A6 with A5 demonstrates that the low-temperature amine removal reaction conditions of A5 are better.

[0413] Example A7 uses polyurethane solid waste and an activator, which are kneaded at low temperature and then extruded at high temperature. Under a back pressure of 2 MPa, the waste enters an active microchannel reactor with a rotating turntable, where it can be rapidly degraded, greatly shortening the degradation time.

[0414] Example A4 uses polyurethane solid waste and an activator to mix at low temperature and then extrude at high temperature, and cools down at the die to obtain solid activated polyurethane particles.

[0415] Comparative Examples 3-8 show the limitations of the open milling method and screw extrusion method for preparing polyurethane powder disclosed in existing patents. Comparative Example 3 uses 20 mm cubic soft foam for open milling, with 30 repetitions, a roller spacing of 0.8 mm, and N2 protection. The main problems are small particle size, low density, large dust, low yield and low activity (low hydroxyl value and amine value).

[0416] Comparative Example 4 uses 80 mm cubic hard foam for open refining, with a repetition number of 30 times, a roller distance of 0.8 mm, and N2 protection, and has the same problem.

[0417] Comparative Examples 5 and 6 use screw extrusion to make powder, and the main problem is that the material bridges and cannot run smoothly.

[0418] Comparative Example 7 uses hard foam powder and an activator for open refining, but cannot be degraded and melted.

[0419] Comparative Example 8 uses twin-screw extrusion at high temperature. The material can be degraded and melted, but the screw slips and the material cannot be discharged continuously. A large amount of activator steam sprays out of the die, and the activated polyurethane is unevenly wet and dry.

[0420] The present invention also provides a method for obtaining a modified polymer by subjecting a resin intermediate prepared by any of the above methods or a resin intermediate prepared by other methods to a grafting reaction treatment, wherein the modified polymer is obtained by treating an initial polymer, and the treatment comprises the following steps:

[0421] Step A1: subjecting the initial polyurethane to a degradation reaction with a degradation agent having an active group, thereby breaking at least a portion of the molecular chains of the initial polymer, and obtaining an activated polyurethane or resin intermediate containing molecular fragments of the initial polymer;

[0422] Step B1: Add the activated polyurethane or resin intermediate in step A to the epoxy resin curing agent and mix evenly to obtain a toughened epoxy resin curing agent. Preferably, mix evenly at 30-160° C., more preferably, mix evenly at 60-130° C., filter after dissolving, more preferably, filter with a sieve of 200 mesh or more.

[0423] The present invention further provides a method for preparing a modified epoxy resin using activated polyurethane or a resin intermediate, comprising the following steps:

[0424] Step C1: at room temperature, epoxy resin (Nan Ya 127), curing agent, catalyst, DMP-30 and other raw materials are mixed uniformly to obtain a mixture;

[0425] Step D1: pouring the mixture into a flat plate mold and then placing it in an oven for heat curing, wherein the heat curing is performed under the following conditions: heating at a rate of 80°C / 0.5 hour to 150°C and maintaining at 150°C for 2 hours;

[0426] Step E1: Turn off the oven heating, and allow the mixture after heating and curing to cool naturally to room temperature (25° C.) to obtain a cured resin plate (modified epoxy resin). Example E8 and Comparative Example E8 are given below for illustration:

[0427] Example E8

[0428] Take 10 grams of the low amine value resin intermediate after the amine is removed by mixing, mix it evenly with 90 grams of methyltetrahydrophthalic anhydride (i.e., anhydride curing agent) and 2 grams of catalyst DMP-30 at 120°C to obtain a toughened epoxy curing agent, then cool it to room temperature, add 108 grams of epoxy resin, and cure the mixture according to the above steps C1, D1 and E1 to obtain a cured resin plate (modified epoxy resin).

[0429] Comparative Example E8

[0430] 108 g of epoxy resin, 100 g of methyltetrahydrophthalic anhydride (i.e., anhydride curing agent) and 2 g of catalyst DMP-30 were mixed evenly to obtain a mixture; the mixture was cured according to the above steps C1, D1 and E1 to obtain a cured resin plate (epoxy resin).

[0431] Table 10: Comparison of properties of cured resin sheets

[0432]

[0433] According to Table 10, it can be seen that the performance of the modified epoxy resin E8 containing the resin intermediate or activated toughening agent of the present invention is improved in tensile strength, impact strength and toughness compared with the epoxy resin of comparative example E8, and the temperature resistance is maintained.

[0434] The present invention also provides a method for obtaining a modified polymer by subjecting a resin intermediate prepared by any of the above methods or a resin intermediate prepared by other methods to a grafting reaction treatment, wherein the modified polymer is obtained by treating an initial polymer, and the treatment comprises the following steps:

[0435] Step A2: subjecting the initial polyurethane to a degradation reaction with a degradation agent having an active group, thereby breaking at least a portion of the molecular chains of the initial polymer, and obtaining an activated polyurethane or resin intermediate containing molecular fragments of the initial polymer;

[0436] Step B2: Add the activated polyurethane or resin intermediate in step A to the polyol component and mix evenly to obtain a modified polyol. Preferably, the mixture is mixed evenly at 30-160° C., and more preferably, the mixture is mixed evenly at 60-130° C.

[0437] The present invention further provides a method for preparing a modified epoxy resin using activated polyurethane or a resin intermediate, comprising the following steps:

[0438] Step C2: at room temperature, uniformly mix the raw materials such as polyol, catalyst, surfactant, foaming agent, etc. according to Table 11 to obtain a polyol mixture, and then uniformly mix the polyol mixture with isocyanate at high speed to obtain a polyurethane mixture;

[0439] Step D2: pouring the polyurethane mixture into a foaming mold for curing;

[0440] Step E2: After 30 minutes, the mold is opened to obtain a foamed polyurethane block (modified polyurethane). Example E9 and Comparative Example E9 are given below for illustration:

[0441] Table 11: Recipe ratio

[0442] Raw material name Example E9 Comparative Example E9 Activated polyurethane or resin intermediate 30 0 Ordinary polyol (NJ-303) / g Jurong Ningwu 70 100 Surfactant AK8860 (Jiangsu Meside) / g 2 2 PC-5 (Evonik Industries) 0.3 0.3 PC-8 (Evonik Industries) 1 1 PC-41 (Evonik Industries) 0.4 0.4 Water / g 2 2 Cyclopentane / g Foshan Shunde Meilong Cyclopentane Chemical Co., Ltd. 11 11 44V20 / gCovestro polymer 164 164

[0443] Example E9

[0444] Take 50 grams of the low amine value resin intermediate after internal mixing to remove amine, and mix 70 grams of N303 evenly to obtain a toughened polyol, then cool to room temperature, add other additives according to the formula ratio shown in the table, and cure the mixture according to steps C2, D2 and E2 to obtain a polyurethane foam (modified polyurethane).

[0445] Comparative Example E9

[0446] 100 g of N303 and other additives were cured according to steps C2, D2 and E2 to obtain a polyurethane foam (polyurethane).

[0447] The physical properties of rigid foam products are tested based on GBT40363-2021 standard. The specific results are shown in Table G1-2 below.

[0448] Table G1-2: Physical property test results of Example E9 and Comparative Example E9

[0449] Foam properties Example E9 Comparative Example E9 Density kg / m3 38.1 38.5 Plane compressive strength / (N / M2) 212.8 174.5 Vertical compressive strength / (N / M2) 207.4 162.4 Thermal conductivity / (W / (mk))*10-2 18.2 19.5

[0450] It can be seen that the performance of the modified polyurethane foam E9 containing the resin intermediate or the activated toughening agent of the present invention is improved in both compression strength and thermal insulation performance compared with the polyurethane foam of comparative example E9.

[0451] The terms and expressions used herein are for descriptive purposes only, and the present invention should not be limited to these terms and expressions. The use of these terms and expressions does not mean to exclude any equivalent features of the illustrations and descriptions (or parts thereof), and it should be recognized that various modifications that may exist should also be included in the scope of the claims. Other modifications, variations and substitutions may also exist. Accordingly, the claims should be deemed to cover all such equivalents.

[0452] Similarly, it should be pointed out that although the present invention has been described with reference to the current specific embodiments, ordinary technicians in this technical field should realize that the above embodiments are only used to illustrate the present invention, and various equivalent changes or substitutions may be made without departing from the spirit of the present invention. Therefore, as long as the changes and modifications to the above embodiments are within the scope of the essential spirit of the present invention, they will fall within the scope of the claims of the present invention.

Claims

1. A method for preparing a resin intermediate, characterized in that: The following steps are involved: Step A: subjecting the initial polymer to a degradation reaction with a degradation agent having an active group, thereby breaking at least a portion of the molecular chains of the initial polymer and obtaining the resin intermediate containing molecular chain fragments of the initial polymer having an active group; Wherein, the mixing method of the initial polymer and the degradation agent includes but is not limited to a combination of one or more of high-speed stirring, centrifugal stirring, kneading, mixing, screw extrusion, grinding, and ball milling; The degradation reaction time is 1-5min, 5-10min, 10-15min, 15-20min, 20-25min, 25-30min, 30-60min, 60-90min, 90-120min, 120-180min, 180-240min, 240-300min, 300-360min or 360-480min.

2. The method for preparing a resin intermediate according to claim 1, characterized in that: The initial polymer is polyurethane waste, and the step A comprises the following steps: Step A: Before the degradation reaction, the polyurethane waste is pulverized to obtain the activated polyurethane, and the pulverization includes one or more combinations of crushing, shearing, grinding, ball milling, grinding, air flow pulverization, ultrasonic pulverization, etc.; wherein the pulverization equipment includes one or a combination of two of an internal mixer or a screw extruder.

3. The method for preparing a resin intermediate according to claim 2, characterized in that: The particle size of the activated polyurethane is not less than 40 meshes, and the product form of the activated polyurethane includes one or more of paste, granules, blocks, strips, sheets, lumps, powders or floccules; the density of the activated polyurethane is in the range of 0.08-0.11 g / cm 3 , 0.11-0.21g / cm 3 ,0.21-0.38g / cm3,0.38-0.81g / cm 3 or 0.81-1.8g / cm 3 ; The polyurethane solid waste content in the activated polyurethane is greater than or equal to 70%; The activated polyurethane contains hydroxyl groups, and the hydroxyl value measured according to the ASTM E1899-2016 test method is 5-400 mgKOH / g, 400-800 mgKOH / g, 800-1200 mgKOH / g or 1200-2000 mgKOH / g; The amine value measured by the method of measuring the amine value with a potentiometric titrator is less than 120 mgKOH / g; The viscosity (25° C.) of the activated polyurethane is 10,000-20,000 mPa·s, 20,000-60,000 mPa·s, 60,000-200,000 mPa·s, 200,000-600,000 mPa·s or 600,000-1,800,000 mPa·s.

4. The method for preparing a resin intermediate according to claim 2, characterized in that: The internal mixer is provided with a clamping component, which applies an additional extrusion force to the material in the internal mixer in addition to the internal mixing roller during the internal mixing process. The clamping component applies the additional extrusion force to the material through a combination of one or more effects of gravity, mechanical force, oil pressure, and air pressure.

5. The method for preparing a resin intermediate according to claim 2, characterized in that: The step A comprises the following steps: Step A1: adding the initial polymer into the screw extruder and subjecting it to the pulverization treatment to obtain an extruded product as the modified polymer; the pulverization treatment includes one or more combinations of crushing, shearing, grinding, ball milling or grinding; The screw extruder includes a single screw extruder or a twin screw extruder; The extrusion time of the material in the screw extruder is 10-20s, 20-40s, 40-60s, 60-80s, 80-100s, 100-120s, 120-160s, 160-200s, 200-240s, 240-300s, 300-360s or 360-480s; The screw speed of the screw extruder is set to 5-10rpm, 10-20rpm, 20-30rpm, 30-40rpm, 40-50rpm, 50-60rpm, 60-70rpm, 70-80rpm, 80-100rpm or 100-200rpm; The extrusion section temperature of the screw extruder is set to 15-20°C, 20-40°C, 40-60°C, 60-80°C, 80-100°C, 100-120°C, 120-160°C, 160-200°C or 200-230°C; and / or The die temperature of the screw extruder is set to 60-90°C, 90-120°C, 120-150°C, 150-180°C or 180-210°C.

6. The method for preparing a resin intermediate according to claim 2, characterized in that: The step A comprises the following steps: Step A2: adding the initial polymer into the internal mixer and subjecting it to the pulverization treatment to obtain an internally kneaded product as the modified polymer, The temperature in the internal mixer is -10-10°C, 10-15°C, 15-30°C, 30-40°C, 40-50°C, 50-60°C, 60-70°C, 70-80°C, 80-90°C, 90-100°C, 100-150°C or 150-230°C.

7. The method for preparing a resin intermediate according to claim 6, characterized in that: In step A2, the banburying time is controlled to be 1-5 min, 5-10 min, 10-15 min, 15-20 min, 20-25 min, 25-30 min or 30-90 min; The stirring speed of the internal mixer is 5-10rpm, 10-20rpm, 20-30rpm, 30-40rpm, 40-50rpm, 50-60rpm, 60-70rpm, 70-80rpm, 80-90rpm, 90-100rpm, 100-300rpm, 300-400rpm, 400-600rpm, 600-800rpm or 800-1000rpm.

8. The method for preparing a resin intermediate according to claim 2, characterized in that: The step A further comprises the following steps: Step A2: adding the initial polymer into the internal mixer and performing the pulverization treatment to obtain an internal mixer product; Step A3: adding the internal mixing product obtained in step A2 into the screw extruder for extrusion or extruding through a screw arranged at the bottom of the internal mixer to obtain an extruded product as the modified polymer; or Step A1: adding the initial polymer into the screw extruder and performing the pulverization treatment to obtain an extruded product; Step A4: adding the extruded product into the internal mixer and performing the pulverization treatment to obtain an internal mixer product as the modified polymer.

9. The method for preparing the resin intermediate according to claim 6, characterized in that: In the step A2, the initial polymer and the activator are mixed together in the internal mixer to obtain the internal mixer product; The activator includes a compound containing one or more functional groups of hydroxyl, amine, carboxyl or anhydride groups, and the compound includes a single compound containing multiple functional groups or a combination of multiple compounds containing multiple functional groups; the mixing ratio of the initial polymer to the activator is 100:5-10, 100:10-15, 100:15-20, 100:20-25, 100:25-30, 100:30-35, 100:35-40, 100:40-45, 100:45-50, 100:50-80, 100:80-110, 100:110-140, 100:140-170, 100:170-200, 100:200-300, 100:300-400 or 100:400-500.

10. The method for preparing the resin intermediate according to claim 9, characterized in that: In the step A2, the activator comprises a polyol or an alcohol composition, The polyol includes any one or more combinations of polyether polyol, sucrose polyol, sorbitol, ethylene glycol, butanediol, diethylene glycol, triethylene glycol, hexanediol, polyethylene glycol, propylene glycol, polypropylene glycol, 3-methyl-1,5-pentanediol, 1,9-nonanediol, neopentyl glycol, and glycerol; The alcohol composition comprises any one or more combinations of the polyol, a metal reagent, a carboxylic acid reagent or an anhydride reagent, and the metal reagent comprises a potassium reagent.

11. The method for preparing a resin intermediate according to claim 8, characterized in that: In the step A2, the initial polymer is mixed with the activator in the internal mixer to obtain the internal mixer product; or In the step A4, the extruded product is mixed with an activator in the internal mixer to obtain the internal mixer product.

12. The method for preparing a resin intermediate according to claim 2, characterized in that: The step A also includes: Step B: subjecting the activated polyurethane obtained in step A to a degradation reaction with a degradation agent containing an active group to break at least a portion of the molecular chains of the activated polyurethane to form a resin intermediate containing initial polymer molecular chain fragments with active groups; The degradation reaction is an alcoholysis reaction.

13. The method for preparing a resin intermediate according to claim 2, characterized in that: The degradation agent comprises a hydroxyl group; The mixing ratio of the activated polyurethane to the degradation agent is 100:5-10, 100:10-15, 100:15-20, 100:20-25, 100:25-30, 100:30-35, 100:35-40, 100:40-45, 100:45-50, 100:50-80, 100:80-110, 100:110-140, 100:140-170, 100:170-200, 100:200-300, 100:300-400 or 100:400-500; the alcoholysis reaction temperature is 120-160°C, 160-180°C, 180-230°C or 230-260°C.

14. The method for preparing a resin intermediate according to claim 1, characterized in that: The step A comprises the following steps: Step C: adding the initial polymer and the degradation agent with active groups into an internal mixer for mixing, breaking at least a portion of the molecular chains of the initial polymer to obtain a resin intermediate containing molecular chain fragments of the initial polymer with active groups, wherein the initial polymer is polyurethane waste.

15. The method for preparing a resin intermediate according to claim 12, characterized in that: The step C comprises the following steps: Step C1: adding the polyurethane waste and the degradation agent with active groups into an internal mixer to obtain an internal mixer product as a resin intermediate.

16. The method for preparing a resin intermediate according to claim 12, characterized in that: The step C comprises the following steps: Step C1: adding the polyurethane waste and the degradation agent with active groups into an internal mixer to obtain an internal mixer product; Step C2: adding the kneaded product obtained in step C1 into a screw extruder for extrusion shaping to obtain an extruded product.

17. The method for preparing a resin intermediate according to claim 1, characterized in that: The step A comprises the following steps: Step D: adding the initial polymer and the degradation agent with active groups into a screw extruder for mixing, breaking at least a portion of the molecular chains of the initial polymer, and obtaining a resin intermediate containing molecular chain fragments of the initial polymer with active groups, wherein the initial polymer is polyurethane waste.

18. The method for preparing a resin intermediate according to claim 17, characterized in that: The step D comprises the following steps: Step D1: adding the polyurethane waste and the degradation agent with active groups into a screw extruder for extrusion shaping to obtain an extruded product as a resin intermediate.

19. The method for preparing a resin intermediate according to claim 17, characterized in that: The step D comprises the following steps: Step D1: adding the polyurethane waste and the degradation agent with active groups into a screw extruder for extrusion molding to obtain an extruded product as a resin intermediate; Step D2: adding the extruded product obtained in step D1 into an internal mixer to obtain an internal mixer product.

20. The method for preparing a resin intermediate according to claim 2, characterized in that: The step A also includes: Step E1: mixing the activated polyurethane with anhydride to remove amines to obtain an activated polyurethane with a low amine value; The mixing ratio of the acid anhydride to the activated polyurethane is 1-10:100, 10-20:100, 20-30:100, 30-40:100, 40-50:100, 50-60:100, 60-80:100 or 80-100:100; the acid anhydride includes one or more of succinic anhydride, maleic anhydride, phthalic anhydride and methyltetrahydrophthalic anhydride; The temperature of the amine removal reaction is 20-30°C, 30-40°C, 40-50°C, 50-60°C, 60-70°C, 70-80°C, 80-90°C, 90-100°C, 100-120°C, 120-150°C, 150-180°C, 180-230°C or 230-250°C. The time of the amine removal reaction is 1-5 min, 5-10 min, 10-20 min, 20-30 min, 30-40 min, 40-50 min, 50-80 min, 80-120 min or 120-240 min.

21. The method for preparing a resin intermediate according to any one of claims 12 to 20, characterized in that: The temperature in the internal mixer is -10-10°C, 10-15°C, 15-30°C, 30-40°C, 40-50°C, 50-60°C, 60-70°C, 70-80°C, 80-90°C, 90-100°C, 100-150°C or 150-230°C; The mixing time is controlled to be 1-5min, 5-10min, 10-15min, 15-20min, 20-25min, 25-30min or 30-90min; The stirring speed of the internal mixer is 5-10rpm, 10-20rpm, 20-30rpm, 30-40rpm, 40-50rpm, 50-60rpm, 60-70rpm, 70-80rpm, 80-90rpm, 90-100rpm, 100-300rpm, 300-400rpm, 400-600rpm, 600-800rpm or 800-1000rpm; The screw extruder performs one or a combination of pulverizing, compressing, shaping, further activating, and degrading; The screw extruder includes a single screw extruder or a twin screw extruder; The extrusion time of the screw extruder is 10-20s, 20-40s, 40-60s, 60-80s, 80-100s, 100-120s, 120-160s, 160-200s, 200-240s, 240-300s, 300-360s or 360-480s; The screw speed of the screw extruder is set to 5-10rpm, 10-20rpm, 20-30rpm, 30-40rpm, 40-50rpm, 50-60rpm, 60-70rpm, 70-80rpm, 80-100rpm or 100-200rpm; The temperature of the conveying section of the screw extruder is set to 15-30°C, 30-40°C, 40-50°C, 50-60°C, 60-70°C, 70-80°C or 80-90°C; The extrusion section temperature of the screw extruder is set to 15-20°C, 20-40°C, 40-60°C, 60-80°C, 80-100°C, 100-120°C, 120-160°C, 160-200°C or 200-230°C; and / or The die temperature of the screw extruder is set to 60-90°C, 90-120°C, 120-150°C, 150-180°C or 180-210°C.

22. The method for preparing a resin intermediate according to any one of claims 14 to 20, characterized in that: The degradation reaction is an alcoholysis reaction; the degradation agent contains a hydroxyl group; The mixing ratio of the polyurethane waste and the degradation agent is 100:5-10, 100:10-15, 100:15-20, 100:20-25, 100:25-30, 100:30-35, 100:35-40, 100:40-45, 100:45-50, 100:50-80, 100:80-110, 100:110-140, 100:140-170, 100:170-200, 100:200-300, 100:300-400 or 100:400-500; the alcoholysis temperature is 120-160°C, 160-180°C, 180-230°C or 230-260°C.

23. A resin intermediate obtained by the preparation method according to any one of claims 1 to 20.

24. The resin intermediate according to claim 23, characterized in that The resin intermediate contains carbamate molecular fragments and hydroxyl groups. According to the ASTM E1899-2016 method test, the hydroxyl value of the resin intermediate is 5-800 mgKOH / g. According to the method for determining the amine value using a potentiometric titrator, the amine value of the resin intermediate is 0-20, 20-40, 40-80, 80-200 or 200-500 mg KOH / g.

25. The resin intermediate according to claim 23, characterized in that: The amine value of the resin intermediate is 0-20, 20-40, 40-80 or 80-120 mg KOH / g, and the resin intermediate does not contain R1-NH-CO-R2 groups; The polyurethane solid waste content in the resin intermediate is greater than or equal to 70%; According to the infrared spectrum test of GB / T 6040-2019, the resin intermediate has a -1 -1780cm -1 There is an obvious infrared absorption peak in the wavenumber range, 1690cm -1 -1780cm -1 The ratio of the peak intensity in the wave number range to the peak intensity in the range of 1480-1570 is in the range of 1.5-1.2, 1.2-1.0, 1.0-0.95, 0.95-0.67, 0.67-0.66, 0.66-0.65 or 0.65-0.60, and the resin intermediate has a peak intensity of 1090-1210 cm -1 There is no obvious infrared absorption peak in the wavenumber range; The viscosity (25° C.) of the resin intermediate is 3000-10000 mPa·s, 10000-20000 mPa·s, 20000-60000 mPa·s, 60000-200000 mPa·s, 200000-600000 mPa·s or 600000-1800000 mPa·s.

26. A method for preparing a low amine value resin intermediate, characterized in that: The following steps are involved: Step A: subjecting the initial polymer to a degradation agent with an active group for degradation reaction, breaking at least a portion of the molecular chain of the initial polymer, and obtaining a resin intermediate containing an active group and an initial polymer molecular chain fragment; Wherein, the mixing method of the initial polymer and the degradation agent includes but is not limited to a combination of one or more of high-speed stirring, centrifugal stirring, kneading, mixing, screw extrusion, grinding, and ball milling; The degradation reaction time is 1-5min, 5-10min, 10-15min, 15-20min, 20-25min, 25-30min, 30-60min, 60-90min, 90-120min, 120-180min, 180-240min, 240-300min, 300-360min or 360-480min; Step E2: mixing the resin intermediate with an acid anhydride to remove amines to obtain a low amine value resin intermediate; The mixing ratio of the acid anhydride to the resin intermediate is 1-10:100, 10-20:100, 20-30:100, 30-40:100, 40-50:100, 50-60:100, 60-80:100 or 80-100:

100.

27. The method for preparing a low amine value resin intermediate according to claim 26, characterized in that: The step E2 comprises: Step E21: adding the resin intermediate and the acid anhydride into the internal mixer to carry out the amine removal reaction to obtain a low amine value resin intermediate; or Step E22: adding the resin intermediate and the acid anhydride into the screw extruder to carry out the amine removal reaction to obtain a low amine value resin intermediate.

28. The method for preparing a low amine value resin intermediate according to claim 27, characterized in that: In the step E21, the rotation speed of the internal mixer is 5-20 rpm, 20-30, 30-40, 40-50, 50-60, 60-70, 70-80, 80-100, 100-120, 120-240, 240-360 or 360-480 rpm.

29. The method for preparing a low amine value resin intermediate according to claim 26, characterized in that: The acid anhydride includes one or more of succinic anhydride, maleic anhydride, phthalic anhydride, and methyltetrahydrophthalic anhydride; The temperature of the amine removal reaction is 20-30°C, 30-40°C, 40-50°C, 50-60°C, 60-70°C, 70-80°C, 80-90°C, 90-100°C, 100-120°C, 120-150°C, 150-180°C, 180-230°C or 230-250°C. The time of the amine removal reaction is 1-5 min, 5-10 min, 10-20 min, 20-30 min, 30-40 min, 40-50 min, 50-80 min, 80-120 min or 120-240 min.

30. A low amine value resin intermediate obtained according to the preparation method according to any one of claims 26 to 29.

31. A production system for a resin intermediate, the production system being applied to the preparation method according to claim 1, characterized in that: The production system includes the internal mixer, which is provided with a clamping component. During the internal mixing process, the clamping component applies an additional extrusion force to the material in the internal mixer in addition to the internal mixing roller. The clamping component applies the additional extrusion force to the material through a combination of one or more effects of gravity, mechanical force, oil pressure, and air pressure.

32. The production system of the resin intermediate according to claim 31, characterized in that: The internal mixer is provided with a pressure control device and / or a condensing device. The pressure control device comprises a pressure relief valve for controlling the pressure in the internal mixer not to exceed a set safety value, and the condensing device is used to collect and condense the steam in the internal mixer and return it to the internal mixer.

33. The production system of the resin intermediate according to claim 31, characterized in that: The production system also includes a screw extrusion device.

34. A polyurethane composite material, characterized in that: Comprising the resin intermediate according to claim 23.

35. An epoxy resin, characterized in that Comprising the resin intermediate according to claim 23.

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