PVC / CPE / nitrile rubber modified material and preparation method thereof

Abstract

The invention discloses a PVC / CPE / nitrile rubber modified material and a preparation method thereof, and belongs to the technical field of high polymer materials. The PVC / CPE / nitrile rubber modified material is prepared from the following raw materials in parts by weight: 40 to 60 parts of PVC, 20 to 30 parts of nitrile rubber, 10 to 20 parts of CPE, 5 to 10 parts of nano diatomite, 7 to 10 parts of plasticizer, 0.5 to 1.5 parts of cross-linking agent, 2 to 5 parts of anti-ultraviolet compatilizer, 2 to 3 parts of stabilizer and 2 to 4 parts of modified flame-retardant lubricant. The PVC / CPE / nitrile rubber modified material prepared by the invention has excellent tensile strength, ageing resistance and flame retardance.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, and in particular to a PVC / CPE / nitrile rubber modified material and a preparation method thereof. Background Art

[0002] With the continuous development of industries such as industry and construction, the requirements for material performance are increasing day by day. Polyvinyl chloride (PVC), as a widely used general-purpose plastic, has the advantages of good mechanical properties, chemical stability and easy processing, but it has problems such as poor impact resistance, heat resistance to be improved and poor compatibility with other materials, which limits its further expansion in some high-end application fields. Chlorinated polyethylene (CPE) has excellent weather resistance, ozone resistance and good compatibility, and can be blended and modified with a variety of polymers to improve the comprehensive performance of the material. Nitrile rubber is known for its excellent oil resistance, wear resistance and elasticity, and is widely used in the field of rubber products.

[0003] However, when blending and modifying PVC, CPE and nitrile rubber, compatibility issues become one of the key challenges. These three materials have significant differences in chemical structure and physical properties. PVC is a polar thermoplastic with a large number of polar chlorine atoms in the molecular chain and a relatively low crystallinity. The molecular structure of CPE is not exactly the same as that of PVC, and the crystallinity and intermolecular forces are also different. The molecular chain of nitrile rubber is more flexible and has a large difference in polarity from PVC and CPE. These differences make it difficult for them to form a uniform microphase structure when blended, and phase separation is prone to occur, which adversely affects the mechanical properties, processing properties and durability of the materials.

[0004] In addition, during the processing, a blending system with poor compatibility may also cause problems such as unstable processing and poor surface quality, such as uneven melt fluidity, warping of products, bubbles or streaks on the surface, etc., which increase production costs and reduce the qualification rate and market competitiveness of products.

[0005] The Chinese invention patent with publication number CN113549255A discloses a method for preparing an aging-resistant nitrile rubber powder-based PVC thermoplastic elastomer and its application in automotive accessories. The nitrile rubber powder-based PVC thermoplastic elastomer comprises the following components by weight: 15-20 parts of polyvinyl chloride or chlorinated polyethylene, 15-20 parts of nitrile rubber or chloroprene rubber, 60-70 parts of waste nitrile rubber powder, 2 parts of regeneration activator, 15 parts of pine tar, 0.8-1.3 parts of compatibilizer, 0.3 parts of vulcanizer, 5 parts of zinc oxide, 0.3 parts of stearic acid, and 0.3 parts of antioxidant 1010. The nitrile rubber powder-based PVC thermoplastic elastomer obtained by the invention has excellent anti-aging performance, but its flame retardant performance is poor. Summary of the Invention

[0006] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a PVC / CPE / nitrile rubber modified material and its preparation method.

[0007] To achieve the above purpose, the present invention is realized through the following technical solutions: A PVC / CPE / nitrile rubber modified material, comprising the following raw materials in parts by weight: PVC: 40 - 60 parts, nitrile rubber: 20 - 30 parts, CPE: 10 - 20 parts, nano-diatomite: 5 - 10 parts, plasticizer: 7 - 10 parts, cross-linking agent: 0.5 - 1.5 parts, anti-ultraviolet compatibilizer: 2 - 5 parts, stabilizer: 2 - 3 parts, modified flame-retardant lubricant: 2 - 4 parts; The anti-ultraviolet compatibilizer is prepared by the following method: S1: Styrene, glycidyl methacrylate, and maleic anhydride react under the action of an initiator to form a triblock copolymer; S2: The triblock copolymer reacts with dodecyl heptaethylene glycol ether under the action of a catalyst to form an alcohol ether-modified triblock copolymer; S3: 2,6-Di-tert-butyl-4-(3-hydroxypropyl)phenol reacts with L-homocysteine under the action of a catalyst to form a dithioblock phenol; S4: The alcohol ether-modified triblock copolymer reacts with the dithioblock phenol to form an anti-ultraviolet compatibilizer.

[0008] In the step S1, the feeding molar ratio of styrene, glycidyl methacrylate, and maleic anhydride is 1:(1 - 2):(1 - 1.5).

[0009] In the step S2, the feeding mass ratio of the triblock copolymer and dodecyl heptaethylene glycol ether is (2 - 3):1.

[0010] In the step S3, the feeding molar ratio of 2,6-di-tert-butyl-4-(3-hydroxypropyl)phenol and L-homocysteine is (2 - 3):1.

[0011] In the step S4, the feeding mass ratio of the alcohol ether-modified triblock copolymer and the dithioblock phenol is (8 - 10):1.

[0012] In the step S1, the initiator is AIBN; in the step S2, the catalyst is triethylamine; in the step S3, the catalyst is p-toluenesulfonic acid.

[0013] The modified flame-retardant lubricant is prepared by the following method: A1: Octadecyl methacrylate reacts with 1,2-bis(bromoacetoxy)ethane under the action of cuprous bromide to form poly(octadecyl methacrylate); A2: Octadecyl methacrylate and 3-buten-1-amine react under the action of cuprous bromide to produce amino-functionalized poly(octadecyl methacrylate). A3: The amino-functionalized poly(octadecyl methacrylate) reacts with DOPO to produce a modified flame retardant lubricant.

[0014] In the step A1, the mass ratio of octadecyl methacrylate to 1,2-bis(bromoacetoxy)ethane in the feed is 10:1.

[0015] In the step A2, the mass ratio of poly(octadecyl methacrylate) to 3-buten-1-amine in the feed is 8:1.

[0016] In the step A3, the mass ratio of amino-functionalized poly(octadecyl methacrylate) to DOPO in the feed is 10:1.

[0017] The plasticizer is one of dioctyl phthalate, dibutyl phthalate, and diisodecyl phthalate; the crosslinking agent is dicumyl peroxide; the stabilizer is one of JX-181 organotin heat stabilizer, JX-107 reverse ester tin heat stabilizer, and JT-101 mercaptostibine heat stabilizer.

[0018] A preparation method of a PVC / CPE / nitrile rubber modified material, comprising the following steps: (1): Weigh by parts by weight: PVC: 40 - 60 parts, nitrile rubber: 20 - 30 parts, CPE: 10 - 20 parts, nano-diatomite: 5 - 10 parts, plasticizer: 7 - 10 parts, crosslinking agent: 0.5 - 1.5 parts, anti-ultraviolet compatibilizer: 2 - 5 parts, stabilizer: 2 - 3 parts, modified flame retardant lubricant: 2 - 4 parts; (2): Add each component into a high-speed mixer for mixing, then introduce the mixed material into a twin-screw extruder for extrusion granulation, and cool and screen with air to obtain the PVC / CPE / nitrile rubber modified material.

[0019] Due to the above technical solutions, the beneficial effects of the present invention include: The anti-ultraviolet compatibilizer prepared by the present invention significantly improves the comprehensive performance of the PVC / CPE / nitrile rubber composite material through the synergistic effect of multiple functional groups. Its alcohol-ether modified triblock copolymer structure forms physical entanglement and chemical interaction with the matrix material, enhances the interfacial compatibility, and constructs a dynamic crosslinking network through dithiobisphenol to effectively transfer and disperse stress, thereby improving the tensile strength and toughness.

[0020] (2) The modified flame-retardant lubricant prepared by the present invention has the advantages of flame retardancy, lubrication, and thermal stability: DOPO provides a phosphorus-nitrogen synergistic flame-retardant mechanism, which can effectively inhibit combustion through gas-phase free radical capture and condensed-phase carbon layer formation; the long-chain alkyl group endows excellent lubricity, reduces the melt viscosity, balances the polar / non-polar structure, and improves the processing fluidity and compatibility. Detailed Embodiments

[0021] The following further illustrates with examples, but the present invention is not limited to these examples.

[0022] Example 1 Preparation of UV-resistant compatibilizer: S1: Under nitrogen protection, add 1000 ml of toluene, 1 mol of styrene, 1 mol of glycidyl methacrylate, and 1 mol of maleic anhydride to the reactor, stir and mix evenly, heat up to 70 °C, then add 10 g of AIBN, react for 8 h, cool to room temperature, add 800 ml of n-hexane, stir to precipitate solids, stand still and then filter by suction, wash three times with acetone (500 ml each time), and vacuum dry at 60 °C for 6 h to obtain a triblock copolymer; the reaction equation is shown as follows: 。

[0023] S2: Add 1200 ml of butanone, 200 g of triblock copolymer, 100 g of dodecyl heptaethylene glycol ether, 25 g of catalyst triethylamine, and 5 g of inhibitor p-hydroxyanisole to the reactor, stir and mix evenly, heat up to reflux and react for 6 h, then cool to room temperature, add 500 mL of ice water to quench, stir for 5 min; extract with 1500 mL of n-hexane, collect the organic phase, wash the organic phase successively with 5 wt% HCl and saturated NaHCO3 three times (500 mL of 5 wt% HCl and 500 mL of saturated NaHCO3 each time), dry with 200 g of anhydrous Na2SO4 for 30 min, filter, distill under reduced pressure at 60 °C for 2 h, and vacuum dry at 70 °C for 6 h to obtain an alcohol ether-modified triblock copolymer; the reaction equation is shown as follows: 。

[0024] S3: Under nitrogen protection, add 400 g of toluene, 0.2 mol of 2,6-di-tert-butyl-4-(3-hydroxypropyl)phenol, and 0.1 mol of L-homocysteine to the reactor, stir and mix evenly, heat up to 80 °C, then add 8 g of p-toluenesulfonic acid, react for 6 h (remove the generated water using a water separator during the reaction), then cool to room temperature, slowly add saturated sodium bicarbonate solution to adjust the pH to neutral, stir well for 30 min, stand still and separate layers, transfer the organic phase to a rotary evaporator, distill under reduced pressure at 60 °C for 4 h to obtain dithioblock phenol; the reaction equation is shown as follows: 。

[0025] S4: Add 400 g of DMF, 10 g of dithioblock phenol, and 80 g of alcohol-ether modified triblock copolymer into the reactor, stir and mix evenly, heat up to 80 °C, then add 150 ml of triethylamine, react for 6 h, cool to room temperature, wash three times with saturated NaHCO3 (200 mL each time), dry with 100 g of anhydrous Na2SO4 for 30 min, filter, distill under reduced pressure at 60 °C for 3 h, and dry in vacuum at 70 °C for 5 h to obtain the ultraviolet-resistant compatibilizer; the reaction equation is shown as follows:

[0026] It should be noted that the drawn equation only represents the reaction sites between functional groups.

[0027] Example 2 Preparation of ultraviolet-resistant compatibilizer: S1: Under nitrogen protection, add 1000 ml of toluene, 1 mol of styrene, 1.5 mol of glycidyl methacrylate, and 1.2 mol of maleic anhydride into the reactor, stir and mix evenly, heat up to 80 °C, then add 10 g of AIBN, after reacting for 6 h, cool to room temperature, add 800 ml of n-hexane, stir to precipitate solids, filter by suction after standing, wash three times with acetone (500 ml each time), and dry in vacuum at 60 °C for 6 h to obtain the triblock copolymer; S2: Add 1200 ml of butanone, 250 g of triblock copolymer, 100 g of dodecyl heptaethylene glycol ether, 25 g of catalyst triethylamine, and 5 g of inhibitor p-hydroxyanisole into the reactor, stir and mix evenly, heat up to reflux and react for 8 h, then cool to room temperature, add 500 mL of ice water to quench, stir for 5 min; extract with 1500 mL of n-hexane, collect the organic phase, wash the organic phase three times with 5 wt% HCl and saturated NaHCO3 (500 mL of 5 wt% HCl and 500 mL of saturated NaHCO3 each time), dry with 200 g of anhydrous Na2SO4 for 30 min, filter, distill under reduced pressure at 60 °C for 2 h, and dry in vacuum at 70 °C for 6 h to obtain the alcohol-ether modified triblock copolymer; S3: Under nitrogen protection, add 400 g of toluene, 0.25 mol of 2,6-di-tert-butyl-4-(3-hydroxypropyl)phenol, and 0.1 mol of L-homocysteine into the reactor, stir and mix evenly, heat up to 90 °C, then add 8 g of p-toluenesulfonic acid, react for 5 h (remove the generated water using a water separator during the reaction), then cool to room temperature, slowly add saturated sodium bicarbonate solution to adjust the pH to neutral, stir well for 30 min, stand and separate layers, transfer the organic phase to a rotary evaporator, and distill under reduced pressure at 60 °C for 4 h to obtain dithioblock phenol; S4: Add 400 g of DMF, 10 g of dithioblock phenol, and 90 g of alcohol-ether modified triblock copolymer into the reactor, stir and mix evenly, heat up to 90 °C, then add 150 ml of triethylamine, react for 5 h, cool to room temperature, wash three times with saturated NaHCO3 (200 mL each time), dry with 100 g of anhydrous Na2SO4 for 30 min, filter, distill under reduced pressure at 60 °C for 3 h, and dry in vacuum at 70 °C for 5 h to obtain the ultraviolet-resistant compatibilizer.

[0028] Example 3 Preparation of ultraviolet-resistant compatibilizer: S1: Under nitrogen protection, add 1000 ml of toluene, 1 mol of styrene, 2 mol of glycidyl methacrylate, and 1.5 mol of maleic anhydride into the reactor, stir and mix evenly, heat up to 85 °C, then add 10 g of AIBN, react for 4 h, cool to room temperature, add 800 ml of n-hexane, stir to precipitate solids, filter by suction after standing, wash three times with acetone (500 ml each time), and dry in vacuum at 60 °C for 6 h to obtain the triblock copolymer; S2: Add 1200 ml of methyl ethyl ketone, 300 g of triblock copolymer, 100 g of dodecyl heptaethylene glycol ether, 25 g of catalyst triethylamine, and 5 g of inhibitor p-hydroxyanisole into the reactor, stir and mix evenly, heat up to reflux and react for 10 h, then cool to room temperature, add 500 mL of ice water to quench, stir for 5 min; extract with 1500 mL of n-hexane, collect the organic phase, wash the organic phase three times with 5 wt% HCl and saturated NaHCO3 (500 mL of 5 wt% HCl and 500 mL of saturated NaHCO3 each time), dry with 200 g of anhydrous Na2SO4 for 30 min, filter, distill under reduced pressure at 60 °C for 2 h, and dry in vacuum at 70 °C for 6 h to obtain the alcohol-ether modified triblock copolymer; S3: Under nitrogen protection, add 400 g of toluene, 0.3 mol of 2,6-di-tert-butyl-4-(3-hydroxypropyl)phenol, and 0.1 mol of L-homocysteine into the reactor, stir and mix evenly, heat up to 100 °C, then add 8 g of p-toluenesulfonic acid, react for 4 h (remove the generated water using a water separator during the reaction), then cool to room temperature, slowly add saturated sodium bicarbonate solution to adjust the pH to neutral, stir well for 30 min, stand and separate layers, transfer the organic phase to a rotary evaporator, and distill under reduced pressure at 60 °C for 4 h to obtain dithioblock phenol; S4: Add 400 g of DMF, 10 g of dithioblock phenol, and 100 g of alcohol-ether modified triblock copolymer into the reactor, stir and mix evenly, heat up to 100 °C, then add 150 ml of triethylamine, react for 4 h, cool to room temperature, wash three times with saturated NaHCO3 (200 mL each time), dry with 100 g of anhydrous Na2SO4 for 30 min, filter, distill under reduced pressure at 60 °C for 3 h, and dry in vacuum at 70 °C for 5 h to obtain the ultraviolet-resistant compatibilizer.

[0029] Example 4 Preparation of modified flame retardant lubricant: A1: Under nitrogen protection, add 400 ml of toluene, 100 g of octadecyl methacrylate, 10 g of 1,2-bis(bromoacetoxy)ethane, and 2 g of pentamethyldiethylenetriamine into a reactor, stir and mix evenly, add 5 g of cuprous bromide, heat up to 70 °C, after reacting for 4 h, cool down to room temperature, and obtain the crude product through a neutral alumina column to remove the copper catalyst. Then add 300 ml of cold acetone, stir, precipitate, filter, and vacuum dry at 70 °C for 6 h to obtain poly(octadecyl methacrylate); the reaction equation is shown as follows: 。

[0030] A2: Under nitrogen protection, add 400 ml of tetrahydrofuran, 80 g of poly(octadecyl methacrylate), 10 g of 3-buten-1-amine, and 5 g of pentamethyldiethylenetriamine into a reactor, stir and mix evenly, add 10 g of cuprous bromide, reflux and react for 2 h, then cool down to room temperature, obtain the crude product through a neutral alumina column to remove the copper catalyst, then add 300 ml of cold acetone, stir, precipitate, filter, and vacuum dry at 70 °C for 6 h to obtain amino-functionalized poly(octadecyl methacrylate); the reaction equation is shown as follows: 。

[0031] A3: Under nitrogen protection, add 400 ml of 1,2-dichloroethane, 10 g of DOPO, 100 g of amino-functionalized poly(octadecyl methacrylate), and 10 ml of triethylamine into a reactor, stir and mix evenly, react at room temperature for 20 h, then perform suction filtration, and wash three times with anhydrous ethanol and 1,2-dichloroethane respectively (200 ml of anhydrous ethanol and 200 ml of 1,2-dichloroethane are used each time), and finally vacuum dry at 50 °C for 8 h to obtain the modified flame retardant lubricant; the reaction equation is shown as follows: 。

[0032] Example 5 Preparation of PVC / CPE / nitrile rubber modified material: (1): Weigh PVC: 400 g, nitrile rubber: 200 g, CPE: 100 g, nano-diatomite: 50 g, plasticizer (dioctyl phthalate): 70 g, crosslinking agent (dicumyl peroxide): 5 g, anti-ultraviolet compatibilizer (prepared in Example 1): 20 g, stabilizer (JX-181 organotin heat stabilizer): 20 g, modified flame retardant lubricant (prepared in Example 4): 20 g; (2): Add each component into a high-speed mixer for mixing. The mixing temperature is 110°C, the mixing speed is 200 r / min, and the mixing time is 20 min. Then, introduce the mixed material into a twin-screw extruder for extrusion granulation. The screw rotation speed of the screw extruder is 20 r / s. The temperature of the conveying section of the twin-screw extruder is 120°C, the melting section temperature is 160°C, the mixing section temperature is 160°C, and the homogenizing section temperature is 145°C. Air-cool and sieve to obtain the PVC / CPE / nitrile rubber modified material.

[0033] Example 6 Preparation of PVC / CPE / nitrile rubber modified material: (1): Weigh PVC: 500 g, nitrile rubber: 250 g, CPE: 150 g, nano-diatomite: 80 g, plasticizer (dibutyl phthalate): 80 g, cross-linking agent (dicumyl peroxide): 10 g, anti-ultraviolet compatibilizer (prepared in Example 2): 30 g, stabilizer (JX-107 inverse ester tin heat stabilizer): 25 g, modified flame-retardant lubricant (prepared in Example 4): 30 g; (2): Add each component into a high-speed mixer for mixing. The mixing temperature is 120°C, the mixing speed is 250 r / min, and the mixing time is 25 min. Then, introduce the mixed material into a twin-screw extruder for extrusion granulation. The screw rotation speed of the screw extruder is 20 r / s. The temperature of the conveying section of the twin-screw extruder is 120°C, the melting section temperature is 160°C, the mixing section temperature is 160°C, and the homogenizing section temperature is 145°C. Air-cool and sieve to obtain the PVC / CPE / nitrile rubber modified material.

[0034] Example 7 Preparation of PVC / CPE / nitrile rubber modified material: (1): Weigh PVC: 600 g, nitrile rubber: 300 g, CPE: 200 g, nano-diatomite: 100 g, plasticizer (diisodecyl phthalate): 100 g, cross-linking agent (dicumyl peroxide): 15 g, anti-ultraviolet compatibilizer (prepared in Example 3): 50 g, stabilizer (JT-101 mercaptoantimony heat stabilizer): 30 g, modified flame-retardant lubricant (prepared in Example 4): 40 g; (2): Add each component into a high-speed mixer for mixing. The mixing temperature is 130°C, the mixing speed is 300 r / min, and the mixing time is 30 min. Then, introduce the mixed material into a twin-screw extruder for extrusion granulation. The screw rotation speed of the screw extruder is 20 r / s. The temperature of the conveying section of the twin-screw extruder is 120°C, the melting section temperature is 160°C, the mixing section temperature is 160°C, and the homogenizing section temperature is 145°C. Air-cool and sieve to obtain the PVC / CPE / nitrile rubber modified material.

[0035] Comparative Example 1 The raw material composition and process of the PVC / CPE / nitrile rubber modified material are basically the same as those in Example 6, except that the anti-ultraviolet compatibilizer is replaced with an anti-ultraviolet compatibilizer prepared by the following method in equal weight: The preparation method of the anti-ultraviolet compatibilizer is basically the same as that in Example 2, except that the dodecyl heptaethylene glycol ether in step S2 is replaced with stearyl alcohol in equal weight.

[0036] Comparative Example 2 The raw material composition and process of the PVC / CPE / nitrile rubber modified material are basically the same as those in Example 6, except that the anti-ultraviolet compatibilizer is replaced with an anti-ultraviolet compatibilizer prepared by the following method in equal weight: The preparation method of the anti-ultraviolet compatibilizer is basically the same as that in Example 2, except that the dodecyl heptaethylene glycol ether in step S2 is replaced with tetraethylene glycol monolauryl ether in equal weight.

[0037] Comparative Example 3 The raw material composition and process of the PVC / CPE / nitrile rubber modified material are basically the same as those in Example 6, except that the anti-ultraviolet compatibilizer is replaced with an anti-ultraviolet compatibilizer prepared by the following method in equal weight: The preparation method of the anti-ultraviolet compatibilizer is basically the same as that in Example 2, except that the dithio hindered phenol in step S4 is replaced with 4-(3-aminopropyl)-2,6-di-tert-butylphenol in equal weight.

[0038] Comparative Example 4 The raw material composition and process of the PVC / CPE / nitrile rubber modified material are basically the same as those in Example 6, except that the modified flame retardant lubricant is replaced with a modified flame retardant lubricant prepared by the following method in equal weight: The preparation method of the modified flame retardant lubricant is basically the same as that in Example 4, except that the addition amount of DOPO in step A3 is increased to 30 g.

[0039] Comparative Example 5 The raw material composition and process of the PVC / CPE / nitrile rubber modified material are basically the same as those in Example 6, except that the modified flame retardant lubricant is replaced with a modified flame retardant lubricant prepared by the following method in equal weight: The preparation method of the modified flame retardant lubricant is basically the same as that in Example 4, except that the addition amount of octadecyl methacrylate in step A1 is replaced with lauryl methacrylate in equal weight.

[0040] The grade of PVC used in the examples and comparative examples of this application is SG-5, produced by Shanghai Chlor-Alkali Chemical Co., Ltd.; the model of CPE used is YH-503, produced by Baling Petrochemical Co., Ltd.; the nitrile rubber model is DN3350, produced by Zeon Corporation of Japan; the nano-diatomite model is Celite® diatomite 535, produced by Shanghai Aladdin Biochemical Technology Co., Ltd.

[0041] The tensile strength tests were carried out on the PVC / CPE / nitrile rubber modified materials prepared in Examples 5-7 and Comparative Examples 1-5. The test method was carried out according to GB / T 1040.2-2006, at a temperature of 23°C, with a 1B type specimen and a tensile speed of 100 mm / min. The test instrument: AI-7000 type electronic tensile machine; the ultraviolet aging test was carried out according to the method of GB / T 16422.3-2014 "Plastics - Methods of exposure to laboratory light sources", and the exposure cycle was selected as the 3rd cycle mode in the standard.

[0042] The vertical burning (UL-94) tests were carried out on the PVC / CPE / nitrile rubber modified materials prepared in Examples 5-7 and Comparative Examples 1-5. The test results are shown in Table 1.

[0043] Table 1 Performance data table of PVC / CPE / nitrile rubber modified materials

[0044] It can be seen from Examples 5, 6, and 7 in Table 1 that the PVC / CPE / nitrile rubber modified materials prepared by the present invention have excellent tensile strength, anti-aging performance, and flame retardant performance.

[0045] In the anti-ultraviolet compatibilizer prepared by the present invention, styrene provides a rigid chain segment, and the interfacial bonding is enhanced through π-π stacking; the unreacted strong polar carboxylic acid groups in maleic anhydride form hydrogen bonds and dipole interactions with the C-Cl bonds of PVC; the epoxy group of glycidyl methacrylate undergoes a ring-opening reaction with the hydroxyl group of dodecyl heptaethylene glycol ether to form a flexible long chain connected by an ether bond. The ether oxygen atoms of the long chain produce strong dipole-dipole interactions with the polar regions of PVC, reducing the degree of phase separation. At the same time, its flexible chain segment improves the molecular chain movement ability of CPE. The disulfide bond reversibly breaks / recombines under stress, dissipating mechanical energy. In addition, the hindered phenol in the anti-ultraviolet compatibilizer can absorb the energy of ultraviolet light, undergo processes such as electronic transitions, and convert the energy of ultraviolet light into other forms of energy such as heat energy and release it, thereby playing an anti-ultraviolet role.

[0046] The modified flame retardant lubricant prepared by the present invention introduces DOPO (phosphorus-containing flame retardant group) and amino group (nitrogen-containing group) into the structure to form a phosphorus-nitrogen synergistic effect. This combination can decompose and generate phosphoric acid substances at high temperature through the dual effects of condensed phase and gas phase flame retardant mechanisms, promote carbonization on the surface of the material, and isolate heat and oxygen. The introduced octadecyl methacrylate provides a long-chain alkyl structure, enhances the flexibility of the molecular chain, improves compatibility with the matrix, avoids phase separation, and gives the material excellent lubricity.

[0047] In comparative example 1, stearyl alcohol contains only a single long-chain alkyl group, which is inserted into the PVC chains only through van der Waals force, and has poor polarity matching, resulting in low tensile strength.

[0048] The modified flame retardant lubricant prepared in Comparative Example 4 has more DOPO functional groups, which affects the dispersion performance of the lubricant during processing.

[0049] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. However, any equivalent changes, modifications and evolutions made by ordinary technicians in the field without departing from the scope of the technical solution of the present invention by using the technical content disclosed above are all equivalent embodiments of the present invention. At the same time, any equivalent changes, modifications and evolutions made to the above embodiments based on the essential technology of the present invention are still within the protection scope of the technical solution of the present invention.

Claims

1. A PVC / CPE / nitrile rubber modified material, characterized in that, It comprises raw materials in the following parts by weight: PVC: 40 - 60 parts, nitrile rubber: 20 - 30 parts, CPE: 10 - 20 parts, nano - diatomite: 5 - 10 parts, plasticizer: 7 - 10 parts, cross - linker: 0.5 - 1.5 parts, anti - ultraviolet compatibilizer: 2 - 5 parts, stabilizer: 2 - 3 parts, modified flame - retardant lubricant: 2 - 4 parts; The anti - ultraviolet compatibilizer is prepared by the following method: S1: Styrene, glycidyl methacrylate, and maleic anhydride react under the action of an initiator to form a triblock copolymer; S2: The triblock copolymer reacts with dodecyl heptaethylene glycol ether under the action of a catalyst to form an alcohol - ether - modified triblock copolymer; S3: 2,6 - Di - tert - butyl - 4 - (3 - hydroxypropyl) phenol reacts with L - homocysteine under the action of a catalyst to form a dithioblock phenol; S4: The alcohol - ether - modified triblock copolymer reacts with the dithioblock phenol to form an anti - ultraviolet compatibilizer.

2. The modified material of PVC / CPE / nitrile rubber according to claim 1, wherein In the step S1, the molar ratio of styrene, glycidyl methacrylate, and maleic anhydride charged is 1:(1 - 2):(1 - 1.5).

3. A PVC / CPE / nitrile rubber modified material according to claim 1, characterized in that, In the step S2, the mass ratio of the triblock copolymer to dodecyl heptaethylene glycol ether charged is (2 - 3):

1.

4. A PVC / CPE / nitrile rubber modified material according to claim 1, characterized in that, In the step S3, the molar ratio of 2,6 - di - tert - butyl - 4 - (3 - hydroxypropyl) phenol to L - homocysteine charged is (2 - 3):

1.

5. A PVC / CPE / nitrile rubber modified material according to claim 1, characterized in that, In the step S4, the mass ratio of the alcohol - ether - modified triblock copolymer to the dithioblock phenol charged is (8 - 10):

1.

6. A PVC / CPE / nitrile rubber modified material according to claim 1, characterized in that, In step S1, the initiator is AIBN; in step S2, the catalyst is triethylamine; in step S3, the catalyst is p - toluenesulfonic acid.

7. A PVC / CPE / nitrile rubber modified material according to claim 1, characterized in that, The modified flame - retardant lubricant is prepared by the following method: A1: Octadecyl methacrylate reacts with 1,2 - bis(bromoacetoxy) ethane under the action of cuprous bromide to form poly(octadecyl methacrylate); A2: Poly(octadecyl methacrylate) reacts with 3 - buten - 1 - amine under the action of cuprous bromide to form amino - poly(octadecyl methacrylate); A3: Amino - poly(octadecyl methacrylate) reacts with DOPO to form a modified flame - retardant lubricant.

8. A PVC / CPE / nitrile rubber modified material according to claim 7, characterized in that, In the step A1, the mass ratio of octadecyl methacrylate to 1,2 - bis(bromoacetoxy) ethane charged is 10:1; in the step A2, the mass ratio of poly(octadecyl methacrylate) to 3 - buten - 1 - amine charged is 8:1; in the step A3, the mass ratio of amino - poly(octadecyl methacrylate) to DOPO charged is 10:

1.

9. A PVC / CPE / nitrile rubber modified material according to claim 1, characterized in that, The plasticizer is one of dioctyl phthalate, dibutyl phthalate, and diisodecyl phthalate; the cross - linker is dicumyl peroxide; the stabilizer is one of JX - 181 organotin heat stabilizer, JX - 107 reverse - ester tin heat stabilizer, and JT - 101 mercaptan stibium heat stabilizer.

10. A method for preparing the PVC / CPE / nitrile rubber modified material according to any one of claims 1-9, characterized in that, It comprises the following steps: (1): Weigh according to parts by weight: PVC: 40 - 60 parts, nitrile rubber: 20 - 30 parts, CPE: 10 - 20 parts, nano-diatomite: 5 - 10 parts, plasticizer: 7 - 10 parts, crosslinking agent: 0.5 - 1.5 parts, anti-UV compatibilizer: 2 - 5 parts, stabilizer: 2 - 3 parts, modified flame-retardant lubricant: 2 - 4 parts; (2): Add each component into a high-speed mixer for mixing, then introduce the mixture into a twin-screw extruder for extrusion granulation, followed by air cooling and sieving to obtain the PVC / CPE / nitrile rubber modified material.

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