Dynamic radiation curing polymer alloy and preparation method thereof

Abstract

The invention discloses a dynamic radiation curing polymer alloy and a preparation method thereof, and belongs to the field of high polymer materials. The polymer alloy is composed of thermoplastic resin and a radiation-curable composition, and the key point in the preparation process is that the radiation-curable composition and the thermoplastic resin are mixed, and then the mixture is irradiated while the mixture is continuously mixed, so that the radiation-curable polymer alloy is obtained. Enabling the radiation-curable polymer in the mixture to be subjected to polymerization and cross-linking reaction under a dynamic condition, and forming a cross-linked dispersed phase in a continuous phase of the thermoplastic resin, so as to prepare the dynamic radiation-curable polymer alloy. The method disclosed by the invention can be used for preparing thermoplastic elastomers or toughened thermoplastic plastics.

Description

Technical Field

[0001] The present invention belongs to the technical field of polymer materials, and more specifically, relates to a dynamic radiation-cured polymer alloy and a preparation method and application thereof. Technical Background

[0002] Traditional rubber vulcanization usually fixes the formulated unvulcanized rubber (i.e., compound rubber) in the mold cavity of the vulcanizer and heats it to a certain temperature to cause the compound rubber to undergo a vulcanization reaction. When the vulcanization reaction occurs, there is no shearing effect caused by material flow or movement inside the compound rubber, so traditional rubber vulcanization can be said to be a "static vulcanization".

[0003] Dynamic vulcanization refers to the process of melt blending unvulcanized rubber with unvulcanized thermoplastic polymers such as polypropylene, polyvinyl chloride, polyamide and other resins in a high-temperature, strong shear blending device, and vulcanizing the rubber phase under the action of a crosslinking agent to obtain vulcanized rubber particles of about micrometer size uniformly dispersed in the resin. The vulcanized rubber particles as the dispersed phase and the thermoplastic resin as the continuous phase together constitute thermoplastic vulcanizates (TPV) or dynamically vulcanized alloys (DVA). These products have both the easy processing and easy recycling of thermoplastics and excellent rubber-like elasticity or leather-like toughness, and are widely used in automotive parts, electronic appliances, construction and other fields.

[0004] Dynamic vulcanization is the process of vulcanization or crosslinking caused by heat. Under heating conditions, the unvulcanized rubber phase becomes a vulcanized rubber phase under the action of a vulcanization system or a crosslinking agent. There are a large number of patent documents at home and abroad that involve the preparation of thermoplastic vulcanizates or the toughening of plastics by dynamic vulcanization. For example, Chinese patent application CN202310410606.1 "A dynamically vulcanized low-temperature resistant high-impact polypropylene alloy and its preparation method" uses SEP or SEPS with a high low-temperature toughening efficiency to improve the low-temperature toughness of the material, and at the same time uses octyl phenolic resin as a vulcanizing agent to dynamically vulcanize EPDM ternary rubber to improve the strength of the material and achieve a balance of rigidity and toughness of the material. U.S. Patent 6020427 "Thermoplastic Vulcanizates of Carboxylated Nitrile Rubber and Polyester Thermoplastics" involves the preparation of a low oil swelling, high melting point carboxylated nitrile rubber thermoplastic vulcanizate.

[0005] Chinese patents CN202111345645.5 “A method for preparing a toughened thermoplastic” and CN202111346105.9 “A toughened polycarbonate material or product and its preparation method” disclose a method for preparing a toughened thermoplastic (such as toughened polycarbonate or toughened polyamide) by first radiation curing and then shear mixing, that is, first applying a radiation-curable (photocurable) coating to the surface of the thermoplastic to be toughened, curing the radiation-curable coating on the surface of the thermoplastic to be toughened by UV radiation treatment, and then shear mixing by a granulator, injection molding machine or extruder, so that the previously cross-linked radiation-curable coating is sheared and refined during shear mixing to form a dispersed phase, thereby obtaining a toughened thermoplastic. In the methods disclosed in these two inventions, radiation curing and shear mixing are not carried out simultaneously.

[0006] The present invention discloses that a radiation-curable polymer undergoes a crosslinking reaction, or a polymerization reaction and a crosslinking reaction, under dynamic conditions by light (especially UV light) or electron beam radiation, and simultaneously forms a crosslinked or cured dispersed phase in a continuous phase of a thermoplastic resin, thereby preparing a dynamic radiation-cured polymer alloy. In other words, the present invention provides a new method for preparing thermoplastic elastomers or toughened plastics by dynamic radiation curing with higher production efficiency.

[0007] Since the relevant terms have not yet been conventionally agreed upon, the "dynamic radiation curing" proposed in the present invention may also be referred to as "dynamic radiation cross-linking", "dynamic radiation vulcanization", or "radiation dynamic cross-linking", "radiation dynamic vulcanization" in some occasions. Depending on the type of radiation used, the word "radiation" can be replaced by specific radiation. For example, when the radiation used is UV light, the "dynamic radiation curing" in the present invention may be referred to as "dynamic light curing", "dynamic light vulcanization", "dynamic light cross-linking", "light dynamic curing", "light dynamic vulcanization", "light dynamic cross-linking", etc., wherein when the light is UV light, "light" may also be replaced by "UV". For simplicity, in the following description of the present invention application, the terms "dynamic light curing", "dynamic electron beam curing" or "dynamic radiation curing" are generally used, but when the prepared polymer alloy contains a cross-linked low modulus and high elastic rubber phase, we will also use the term "dynamic radiation vulcanization". Summary of the invention

[0008] Purpose of the invention: The purpose of the present invention is to provide a dynamic radiation-cured polymer alloy that can be used as a thermoplastic elastomer or a toughened plastic and a preparation method thereof.

[0009] Unless otherwise specified, the parts described in the present invention are parts by weight, the percentage content is the percentage content by weight, and the ratio is the weight ratio.

[0010] Technical solution: The dynamic radiation-cured polymer alloy disclosed in the present invention is prepared by dynamic radiation curing of a thermoplastic resin and a radiation-curable composition, and is composed of 10-98 parts of a thermoplastic resin as a continuous phase and 2-90 parts of a cross-linked radiation-curable composition as a dispersed phase. In addition, the dynamic radiation-cured polymer alloy may also contain 0-15 parts of additives such as a compatibilizer. The compatibilizer is also called a compatibilizer, and its function is to promote the ability of the thermoplastic resin and the radiation-curable radiation-curable composition to accommodate each other and form a macroscopically uniform material, that is, to promote the compatibility between the two.

[0011] In the present invention, the radiation curable composition is a photocurable composition, an electron beam curable composition, or a radiation curable rubber or rubber compound. The radiation curable rubber or rubber compound includes radiation curable simple raw rubber, such as natural rubber, butadiene rubber, nitrile rubber, etc., and also includes a radiation curable natural rubber and a synthetic rubber compound.

[0012] Dynamic radiation curing is relative to static radiation curing. Static radiation curing is conventional radiation curing, the process of which is to coat, apply or place a radiation curable material (such as a radiation curable coating, a radiation curable adhesive or a radiation curable rubber, etc.) on a substrate or in an irradiated environment, so that the radiation curable material is basically stationary relative to the substrate, or the interior or surface of the radiation curable material is not subjected to shearing, and then radiation curing is performed. In short, the characteristic of static radiation curing is that the radiation curable material is not subjected to external shearing during the curing process, and no mixing process is involved.

[0013] The dynamic radiation curing disclosed in the present invention is similar to dynamic vulcanization, but also different from dynamic vulcanization. Dynamic radiation curing also occurs in the shear mixing process of the radiation-curable composition and the thermoplastic resin, but in dynamic radiation curing, the radiation-curable composition undergoes a cross-linking reaction under the action of radiation and is distributed as a dispersed phase in the unvulcanized thermoplastic resin. In dynamic vulcanization, the temperature rises due to the action of heat, and the cross-linking agent takes effect, thereby causing a cross-linking reaction in the cross-linkable rubber phase. Dynamic radiation curing is not due to the action of heat, but due to the action of radiation, especially due to the action of ultraviolet light and electron beam radiation, which causes the radiation-curable composition to undergo a cross-linking reaction caused by radiation, or a polymerization reaction and a cross-linking reaction caused by radiation.

[0014] The photocurable composition of the present invention is composed of at least two substances, namely, a photocurable oligomer and a photoinitiator. It may also be composed of a photocurable oligomer, a photocurable monomer and a photoinitiator, or it may be composed of a photocurable oligomer, a photocurable monomer, a photoinitiator, and one or more of an auxiliary initiator, a solvent, a reactive diluent, a compatibilizer, a plasticizer, a light stabilizer, a heat stabilizer, an antioxidant, a solid pigment, a color paste, a filler, a defoamer, a coupling agent, a leveling agent, a wetting dispersant and a compatibilizer.

[0015] The electron beam curable composition is composed of an electron beam curable oligomer, or is composed of an electron beam curable oligomer and one or more selected from an electron beam curable monomer, a sensitizer, a reactive diluent, a solvent, a plasticizer, a light stabilizer, a heat stabilizer, a solid pigment, a color paste, a filler, a defoamer, a coupling agent, a leveling agent, a wetting dispersant and a compatibilizer. If the electron beam curable composition contains an electron beam curable monomer, then during dynamic electron beam curing, the electron beam curable composition undergoes polymerization and crosslinking reactions.

[0016] The rubber or rubber compound is a rubber containing unsaturated bonds or a radiation-curable rubber compound. Rubber raw rubber containing unsaturated bonds, such as natural rubber, butadiene rubber, styrene-butadiene rubber, nitrile rubber, EPDM rubber, etc., can be used as electron beam-curable compositions. These rubber compounds (i.e. rubber compounds) containing unsaturated bonds can also be used as electron beam-curable compositions. During dynamic electron beam vulcanization, only crosslinking reaction or vulcanization reaction occurs in the rubber or its rubber compound.

[0017] As an example, the radiation curable composition may contain 100 parts of radiation curable oligomer, 0-10 parts of initiator, 0-100 parts of radiation curable monomer, 0-10 parts of co-initiator, 0-10 parts of sensitizer, 0-100 parts of solvent, 0-100 parts of reactive diluent, 0-50 parts of plasticizer, 0-5 parts of solid pigment, 0-5 parts of color paste, 0-75 parts of filler, 0-2.5 parts of coupling agent, 0-2.5 parts of defoamer, 0-2.5 parts of leveling agent, 0-2.5 parts of wetting and dispersing agent and 0-10 parts of adhesion promoter; wherein the electron beam curable composition can be composed only of radiation curable oligomer or electron beam curable oligomer without photoinitiator or electron beam initiator.

[0018] The radiation-curable oligomer includes, but is not limited to, one or more of radiation-curable pure acrylate polymers, polyurethane acrylates, polyurethane methacrylates, unsaturated polyesters, epoxy acrylates, epoxy methacrylates, polyester acrylates, polyether acrylates, silicone acrylate polymers, epoxy resins, water-based radiation-curable oligomers, rubbers containing unsaturated bonds, or a mixture of the above oligomers or active solvents or radiation-curable monomers;

[0019] The reactive solvent, reactive diluent or radiation curable monomer is a monofunctional, difunctional, trifunctional or high-functional monomer, or a mixture of these monomers.

[0020] The radiation curable composition contains at least one bifunctional, trifunctional or multifunctional radiation curable oligomer, or at least one bifunctional, trifunctional or multifunctional radiation curable monomer.

[0021] The initiator in the present invention refers to a photoinitiator. The photoinitiator can be either a Class I or Class II photoinitiator. The Class I and Class II photoinitiators are selected from one or a combination of two or more of benzophenone, 1-hydroxy-cyclohexyl-phenyl ketone, benzoin dimethyl ether, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and isopropylthiophenone; the photoinitiator is a single photoinitiator, or is composed of two or more photoinitiators.

[0022] In addition to the photoinitiator, a co-initiator may be added to increase the polymerization rate or the degree of crosslinking. The co-initiator is selected from one or more compounds prepared by Michael addition reaction of triethylamine, diethanolamine, triethanolamine, N-methylethanolamine, N,N-dimethylethanolamine, N,N-diethylethanolamine, ethyl 4-dimethylaminobenzoate, diethylamine or diethanolamine with difunctional acrylate or multifunctional acrylate.

[0023] The solvent includes, but is not limited to, alcohols, esters, ketones, aromatic hydrocarbons, alcohol ethers, ether ester solvents, dimethyl sulfoxide, N,N-dimethylformamide, dimethyl carbonate, nitromethane, nitroethane, 1-nitropropane or water with a boiling point below 200° C. at normal pressure that do not participate in chemical reactions. The solvent does not have the ability to polymerize or crosslink.

[0024] The plasticizer includes, but is not limited to, phthalates, phosphates, polyol esters, dibasic fatty acid esters, epoxies, citrate compounds or polymeric plasticizers having a boiling point higher than 250° C. at normal pressure.

[0025] The solid pigment is a solid inorganic pigment, an organic pigment or a mixture thereof.

[0026] The color paste contains a solid pigment dispersed in a solvent or resin and a small amount of active agent concentrate, and is a concentrated paste of solid pigment.

[0027] The filler includes but is not limited to inorganic filler or organic filler; the inorganic filler includes but is not limited to calcium carbonate, calcium sulfate, talcum powder, kaolin, microsilica powder, diatomaceous earth or white carbon black, and the organic filler is nanocellulose, silicone resin powder or rubber powder.

[0028] The coupling agent is one or two of a titanate coupling agent, an aluminate coupling agent, a bimetallic coupling agent, a phosphate coupling agent, a borate coupling agent or a chromium complex coupling agent.

[0029] Defoamers, leveling agents, wetting and dispersing agents, adhesion promoters, etc. can all be selected from commercially available industrial products commonly used in radiation-curing coatings, inks, adhesives, and other industries.

[0030] As an example, the dynamic radiation-cured polymer alloy contains 0.2%-10% polymer compatibilizer; the polymer compatibilizer includes but is not limited to maleic anhydride, acrylic acid or methacrylate grafted polyolefin or polyolefin elastomer, block copolymer of polysiloxane and polycarbonate, styrene-maleic anhydride copolymer and styrene-acrylonitrile-methacrylate glycidyl copolymer, etc. The compatibilizer is added to promote the mixing degree of the thermoplastic resin and the radiation-curable radiation-curable composition in the dynamic radiation-cured polymer alloy during mixing, improve the adhesion between the dispersed phase and the continuous phase interface layer, promote phase dispersion, stabilize the morphological structure, and reduce the interfacial tension between the two phase components by means of the bonding force between polymer molecules, increase the uniformity of the blending system, and reduce phase separation, so as to achieve the purpose of improving the comprehensive performance of the polymer alloy.

[0031] The radiation curable composition may be in liquid, paste or raw rubber form and may be flowable before dynamic radiation curing. The viscosity measured at 25° C. using a rotational viscometer may be 100-200000 Pa s.

[0032] Any thermoplastic resin that can be thermoplastically processed by mixing equipment such as an open mixer, internal mixer, or granulator can be used to prepare a dynamic radiation-cured polymer alloy. Different thermoplastic resins can be selected according to the product application or performance requirements, including but not limited to polyethylene, polypropylene, polyvinyl chloride, chlorinated polyvinyl chloride, chlorinated polyethylene, polystyrene, polymethyl methacrylate, polyamide, polycarbonate, polyester, polyacrylic acid, acrylonitrile-styrene-butadiene polymer, acrylonitrile-styrene polymer, polyurethane, polyoxymethylene, polyphenylene ether, polysulfone, polyethersulfone, polyphenylene sulfide, polyaryletherketone resin, a blend of one of them, or a chemically modified product of one of them, or one of the thermoplastic elastomers selected from urethane, ester, amide, olefin, ethylene, styrene, diene, vinyl chloride, silicone or organofluorine; the thermoplastic resin is a transparent, translucent or opaque thermoplastic elastomer of the above single component. The thermoplastic resin may be a thermoplastic resin or a polymer blend containing the above thermoplastic resin, a thermoplastic resin containing glass fiber, Kevlar fiber, carbon fiber, boron fiber or metal fiber, a thermoplastic resin containing flame retardant, antioxidant, light stabilizer, heat stabilizer, foaming agent, colorant, plasticizer, lubricant, impact agent, antibacterial agent, antistatic agent or conductive filler, or a thermoplastic resin containing cheap filler, wherein the cheap filler is calcium carbonate, magnesium carbonate, dolomite, kaolin, diatomaceous earth, mica powder, calcium silicate, wollastonite, quartz powder, glass powder, glass microbeads, attapulgite, zeolite, talc, montmorillonite, bentonite, asbestos, barium sulfate, calcium sulfate, calcium sulfite, graphite, carbon black, white carbon black, aluminum oxide, magnesium oxide, titanium dioxide, zinc oxide, iron oxide, aluminum hydroxide or magnesium hydroxide. The thermoplastic resin may also contain other components, such as flavoring agents, etc.

[0033] Genuine, secondary, sprue or recycled materials of thermoplastic resins can all be used to prepare dynamic radiation-cured polymer alloys. The genuine materials are materials produced by thermoplastic resin factories that meet various quality inspection standards; secondary materials refer to materials that do not meet various quality inspection standards when leaving the factory, but are still useful, relative to genuine materials. Compared with genuine materials, secondary materials are materials of relatively lower quality. The sprue refers to the material that remains in the gate and runner parts of thermoplastic resins during the injection molding process in order to form products; the recycled materials refer to the materials that are recycled after the thermoplastic resins are formed into products and used.

[0034] The key and special feature of preparing dynamic radiation-cured polymer alloys lies in dynamic radiation curing, that is, when the materials are mixed, the photocurable composition or electron beam-curable composition in the materials undergoes a cross-linking reaction, or a polymerization reaction and a cross-linking reaction, and is uniformly dispersed in the thermoplastic resin.

[0035] Specifically, the preparation method of the dynamic radiation curing polymer alloy comprises the following steps:

[0036] Step A, weighing the raw materials according to the weight ratio, mixing them evenly to prepare a radiation curable composition; or, purchasing the radiation curable composition from the market according to the weight ratio; the simplest radiation curable composition is a raw rubber of natural rubber or synthetic rubber containing unsaturated bonds, such as a raw nitrile rubber, which can be used as the radiation curable composition;

[0037] Step B, uniformly mixing the radiation curable composition obtained in step A and a thermoplastic resin with a mixing device; the mixing device is an open mixer, a kneading mill, a internal mixer, a screw granulator, an extruder, a calender or an injection molding machine;

[0038] Step C, continuing the mixing operation, while turning on UV light or electron beam radiation to irradiate the mixed materials, so that the radiation-curable composition in the materials undergoes a radiation curing reaction, and the obtained material is a dynamic radiation-cured polymer alloy;

[0039] Step D, pelletizing the material extruded by the screw granulator in step C to prepare a dynamic radiation-cured polymer alloy pellet with a weight of less than or equal to 1.0 g per pellet; or cutting, chopping, grinding, tearing or crushing the material obtained by an open mill, kneading mill, internal mixer, extruder, calender or injection molding machine in step C with a pulverizer to obtain a granular dynamic radiation-cured polymer alloy, or further granulating the obtained granular dynamic radiation-cured polymer alloy with a screw granulator to prepare a dynamic radiation-cured polymer alloy pellet with a weight of less than or equal to 1.0 g per pellet;

[0040] Step E: Processing the material obtained by the extruder in step C into an extruded product of a dynamic radiation-cured polymer alloy; processing the material obtained by the injection molding machine in step C into an injection molded part of a dynamic radiation-cured polymer alloy; or, further thermoplastic processing the material obtained in step D to obtain an injection molded product, an extruded product or a calendered product.

[0041] The aforementioned step B and step C are performed once or multiple times. For example, step B and step C are referred to as B and C respectively, and the process can be BC, BBC, BCC or BCBC.

[0042] The mixing equipment used is one or more of an open mixer, a kneading mill, an internal mixer, a screw granulator, an extruder, a calender or an injection molding machine. The mixing of materials and the crosslinking of materials, or the mixing of materials and the polymerization and crosslinking of materials, take place in these equipments.

[0043] In the present invention, the UV light source used for radiation curing is a mercury lamp, an electrodeless lamp, a metal halide lamp or an LED lamp; or, the electron beam used for radiation curing is a low-energy electron beam, a medium-energy electron beam or a high-energy electron beam. The higher the energy of the electron beam, the greater the depth of the electron beam into the material, which can accelerate the overall electron beam radiation curing efficiency.

[0044] The dynamically radiation-cured polymer alloy prepared in the present invention can be a thermoplastic elastomer, or a toughened plastic or a reinforced plastic.

[0045] Beneficial effects:

[0046] The method for preparing a polymer alloy by dynamic radiation curing disclosed in the present invention has the following beneficial effects:

[0047] (1) High production efficiency: The dynamic radiation curing process can complete the two processes of mixing and curing (or vulcanization, cross-linking) in a shorter time. Moreover, the curing initiated by UV light or electron beam also takes a shorter time, which can greatly improve production efficiency.

[0048] (2) Energy saving: Since radiation curing does not require high temperatures to occur, the dynamic radiation curing process can complete the curing process at a lower temperature. In addition, the mixing and curing processes are short, thus saving energy costs.

[0049] (3) Good product processing performance: The polymer alloy prepared by the dynamic radiation curing process has excellent processing performance and exhibits the characteristics of thermoplastics at high temperatures. It can be quickly, economically and conveniently processed and can be processed by traditional thermoplastic processing methods such as injection and extrusion to prepare injection molded and extruded products.

[0050] (4) Good product performance: Through the dynamic radiation curing process, thermoplastic blends or polymer alloys with excellent performance can be produced. For example, the obtained blends can obtain excellent physical and mechanical properties, such as elasticity and high strength and high modulus, and have good weather resistance, aging resistance and chemical corrosion resistance.

[0051] (5) Environmental protection: The polymer alloy obtained by the dynamic radiation curing process has the characteristics of recyclable sprue materials and waste materials, which is beneficial to environmental protection. In addition, no harmful gases are released during the dynamic radiation curing process, which is harmless to the environment and operators. In particular, in the case of dynamic electron beam curing, it is not necessary to introduce expensive photoinitiators into the formula, so the raw material cost is more economical and more harmless to the human body and the environment. DETAILED DESCRIPTION

[0052] Unless otherwise specified, the parts in the formula of each embodiment are parts by weight; the ratios between materials are weight ratios.

[0053] The melt mass flow rate of the material was tested according to ISO 1133 standard, the test condition was 300℃ / 1.2kg, and the sample used for the test was the pellets before injection molding. The density of the material was measured according to ISO 1183, and the pencil hardness was tested according to ASTM D3363 (Mitsubishi pencil, 500g load); the tensile strength and elongation at break of the material were tested according to ISO 527-1 standard, and the tensile rate was 50mm / min; the flexural strength and flexural modulus of the material were tested according to ISO178 standard, and the test rate was 2mm / min; the notched impact strength of the material was tested according to ISO180 standard, and a notch sample making machine was used to prepare a "V"-shaped notch with a notch depth of 2mm. The heat deformation temperature of the material was tested according to ISO 75-1 standard, and the heating rate was 120℃ / min.

[0054] Example 1

[0055] The dynamic light-curable polymer alloy prepared in this embodiment is composed of a photocurable composition obtained by dynamic light curing as a dispersed phase and a polycarbonate as a continuous phase. The polycarbonate used is produced by Ningbo Zhetie Dafeng Chemical Co., Ltd. and has a brand name of PC02-10R. The monomers and oligomers in the photocurable composition are selected from Arkema Series of products. The basic formula of the photocurable composition in this embodiment is: 75 parts of polyurethane acrylate (brand name CN965NS, viscosity 9975cps / 60°C, Tg-37°C), 15 parts of isodecyl acrylate (brand name SR395NS, Tg-60°C), 5 parts of triethylene glycol dimethacrylate (brand name SR205NS, Tg-7.6°C), and 5 parts of photoinitiator 1173 (2-hydroxy-2-methyl-1-phenyl-1-propanone).

[0056] A photocurable composition was prepared according to the above basic formula. Polycarbonate and the photocurable composition were mixed in a ratio of 100:5, stirred evenly, and put into a twin-screw granulator with a barrel inner diameter of 35 mm, a screw aspect ratio of 48, and a screw speed of 350 rpm for melt granulation. The feeding section of the twin-screw granulator was 200-220°C, the melting section temperature was 260-270°C, the homogenization section temperature was 230-250°C, and the head temperature was 220-240°C.

[0057] A window made of quartz glass is installed above the barrel of the twin-screw granulator 25 mm from the die head. The area of ​​light that can be transmitted through the quartz glass window is 375.0×2.5 mm. A mercury lamp as an ultraviolet light source is placed above the quartz glass window. The length of the mercury lamp tube is 360 mm, the power is 5 kW, and the main emission wavelength is 365 nm, followed by 313 nm and 303 nm. A reflector is placed above the mercury lamp, which is used to reflect UV light into the quartz glass window and prevent UV light from leaking out.

[0058] The pellets obtained by granulation were allowed to stand for 24 hours and then dried in an oven at 110° C. for 4 hours before injection molding; the injection molding temperature was 270-290° C., the injection molding pressure was 70-90 MPa, and the mold temperature controller was set at 100-110° C. After the injection molding was completed, the obtained sample was marked as Example 101. The samples were placed in a constant temperature chamber for 24 hours before various tests were performed.

[0059] The pellets obtained during the sample preparation process of Example 101 are once again put into the original twin-screw granulator and pelletized again with the UV light source turned on. Then, injection molding is performed as in Example 101, and the obtained sample is marked as Example 102.

[0060] The sample of comparative example 110 was obtained by injection molding pure polycarbonate PC02-10R pellets (ie, new material) after being directly dried in an oven at 110° C. for 4 hours.

[0061] The sample preparation process of comparative example 111 is the same as that of example 101, but the material used is pure polycarbonate PC02-10R (i.e., new material). The new material is pelletized once by the above-mentioned twin-screw pelletizer, and then the obtained pellets are injection molded.

[0062] The sample preparation method of Comparative Example 112 is the same as that of Example 101, and is also composed of 100:5 polycarbonate and photocurable composition, but the UV light source is not turned on during pellet extraction.

[0063] The performance tests of each sample are shown in Table 1.

[0064] Table 1. Physical properties of materials obtained by different methods

[0065]

[0066]

[0067] As can be seen from Table 1, the notched impact strength of the polycarbonate alloy prepared by dynamic photocuring (Example 101) is about 5 times that of the virgin polycarbonate (Comparative Examples 110 and 111). It can be seen that the polycarbonate alloy prepared in Example 101 is a toughened polycarbonate material with good impact resistance. Compared with the un-toughened virgin material, the pencil hardness, tensile strength, elongation at break, and heat distortion temperature of this toughened polycarbonate material remain basically unchanged or change slightly.

[0068] If a photocurable composition is added to polycarbonate without dynamic photocuring, the tensile strength of the resulting polymer alloy will decrease significantly, and the heat distortion temperature will also decrease, as shown in Comparative Example 112.

[0069] By comparing Example 101 and Example 102, it can be seen that the polymer alloy with dynamic photocuring has better thermoplasticity and repeat processing performance. After two pelletizations, the physical properties of the pellets basically remain unchanged.

[0070] Example 2

[0071] The open mill used in this example was manufactured by Dongguan Xihua Testing Instrument Co., Ltd., with the model XH-401BE. The UVLED linear light source was produced by Shanghai Leihe Electronic Technology Co., Ltd., with the model ULLS10-300. Its electric power is 600W, and it can emit a 10*400mm linear light spot with a main wavelength of 365nm. The UVLED linear light source is located directly above the two rolls of the open mill and is parallel to the axis line of the two rolls. Its light-emitting position is 15 cm higher than the two rolls of the open mill, and the light emission is aligned with the middle of the two rolls of the open mill.

[0072] Polyvinyl chloride (PVC) is a resin that is prone to decomposition at high temperatures. Therefore, its processing temperature must be as low as possible to reduce its thermal decomposition during processing.

[0073] The dynamic light-curing polymer alloy prepared in this embodiment is a PVC thermoplastic elastomer, which is prepared from soft PVC and a light-curable composition, wherein the formula of the soft PVC is: 100 parts of PVC, 60 parts of plasticizer DOP, and 5 parts of calcium-zinc composite stabilizer. Among them, PVC is a product of Sinopec Qingdao Refining and Chemical Co., Ltd., with a brand name of SG-3; the calcium-zinc composite stabilizer is a product of Shandong Baolilai Plastic Additive Co., Ltd. The formula of the photocurable composition of this embodiment is: 75 parts of aromatic polyurethane acrylate (brand name CN9782, viscosity 42000cps / 60°C, Tg-32°C), 15 parts of tetrahydrofuran acrylate (brand name SR285, Tg-15°C), 4 parts of (15) ethoxylated trimethylolpropane triacrylate (brand name SR9035, Tg-32°C), 1 part of pentaerythritol tetraacrylate (brand name SR295NS, Tg 103°C), 3 parts of photoinitiator 1173 (2-hydroxy-2-methyl-1-phenyl-1-propanone), and 2 parts of photoinitiator TPO (2,4,6-trimethylbenzoyl-diphenylphosphine oxide). Raw materials without indicating the manufacturer or brand name are all commercially available industrial products.

[0074] The components of the photocurable composition are mixed according to the above ratios and stirred evenly to obtain a paste. PVC, DOP and calcium-zinc composite stabilizer are mixed evenly with a high-speed kneader to obtain a soft PVC mixed powder.

[0075] Take 825g of the above mixed powder, use an open mill with a roller temperature of 155-158°C to fully melt and plasticize, then add 150g of the above paste, mix for about 2 minutes to make the materials on the open mill basically mixed, then turn on the UVLED line light source located above the double rollers of the open mill to UV irradiate the mixture, continue mixing for 5 minutes under UV irradiation, maintain an appropriate amount of accumulation, and assist with cutting and refining, so that the mixture is turned in the roller gap and the mixture is continuously taken out of the package roller, then thinly pass three times, and then produce a sheet with a thickness of 2.5-3.0cm, and turn off the UVLED line light source. After heating at 150°C for 5 minutes on a 25-ton flat vulcanizer, hot press to shape, and then cool under pressure on a cold plate to obtain the sample required for the test, and the obtained sample is marked as Example 201.

[0076] According to the proportions of Example 201, the components of the photocurable composition were weighed so that the total weight of the photocurable composition was 150 g. 825 g of the soft PVC mixed powder was mixed with 150 g of the components of the photocurable composition and stirred evenly to obtain a mixed material. The mixed material was then mixed and prepared according to the mixing and sample preparation method of Example 201 to obtain the sample required for the test. The obtained sample was marked as Example 202.

[0077] 975 g of the soft PVC mixed powder was taken and a sample was prepared according to the mixing and sample preparation method of Example 202. This sample was a pure soft PVC sample. The obtained sample was marked as Comparative Example 210.

[0078] The formulation and all process parameters of Comparative Example 211 were the same as those of Example 201, but the UVLED linear light source was not turned on during mixing.

[0079] The two sides of the sample of comparative example 211 located 15 cm below the light source were irradiated for 10 minutes respectively using a UVLED line light source, and the sample was continuously moved back and forth during the irradiation. The obtained sample was marked as comparative example 212.

[0080] Table 2. Physical properties of materials obtained by different methods

[0081]

[0082] As can be seen from Table 2, the polymer alloy of PVC and the photocurable composition (Example 201) prepared by dynamic photocuring is closer to the properties of rubber, and its hardness is lower than that of pure soft PVC (Comparative Example 210), and its compression permanent deformation is also smaller than that of pure soft PVC. Therefore, the polymer alloy prepared in Example 201 is a thermoplastic elastomer with better elasticity than pure soft PVC.

[0083] Comparing the test results of the samples of Example 202 and Example 201, it can be seen that the different order or method of adding materials during mixing has little effect on the properties of the obtained polymer alloy. As long as dynamic light curing is implemented, the obtained samples have a small compression set.

[0084] Comparing the test results of Example 201 and Comparative Example 211, it can be seen that when the photocurable composition is added to pure soft PVC without dynamic photocuring, the tensile strength and elongation at break of the obtained sample are low, and the compression permanent set is large.

[0085] Comparative Example 212 is a sample prepared by "static light curing". Compared with Example 201, the obtained sample also has low tensile strength and elongation at break, and large compression permanent deformation.

[0086] Example 3

[0087] This embodiment uses a method of dynamic vulcanization by electron beam radiation to prepare a PVC thermoplastic elastomer. The electron beam radiation equipment used in this embodiment is modified from a desktop self-shielded electron accelerator MEB-120 produced by Sichuan Zhiyan Technology Co., Ltd., so that the electron beam it emits can safely and effectively irradiate the material between the rolls of the mixing mill; after the machine is turned on, the electron beam energy is 120keV.

[0088] The PVC thermoplastic elastomer is composed of soft PVC and nitrile rubber (NBR), and the specific formula is: 100 parts of PVC, 60 parts of plasticizer DOP, 5 parts of calcium-zinc composite stabilizer, and 30 parts of NBR. The nitrile rubber used is NBR2907, a product of Lanzhou Petrochemical Company, and its acrylonitrile content is 29%. PVC, DOP and calcium-zinc composite stabilizer are kneaded into soft PVC powder for standby use.

[0089] 100 parts of NBR and 1.0 part of triallyl isocyanurate as a radiation sensitizer were mixed with an open mill for 3 minutes to obtain an NBR rubber mix. 150g of NBR rubber mix and 825g of soft PVC powder were mixed with an open mill with a roller temperature of 155-158°C for about 2 minutes, and thinly passed 3 times to make the materials on the open mill basically mixed and uniform, continue mixing and turn on the desktop self-shielded electron accelerator located above the double rollers of the open mill to irradiate the materials turning in the roller gap of the open mill with electron beams, mix for about 10 minutes under the condition of electron beam irradiation, and then turn off the desktop self-shielded electron accelerator after the material absorption dose is between 25-50KGy, and then produce a sheet with a thickness of 2.5-3.0cm. After heating at 150°C for 5 minutes on a 25-ton flat vulcanizer, hot pressing was performed, and then pressure-maintained cooling was performed on a cold plate to obtain the sample required for the test, and the obtained sample was marked as Example 301.

[0090] Example 302 is a method in which the sample obtained in Example 301 is heated to 150°C, kneaded for about 10 minutes under the same electron beam irradiation conditions as in Example 301, and then sheeted and pressed.

[0091] The formulation and all process parameters of Comparative Example 311 are the same as those of Example 301, but the electron beam irradiation device is not turned on during mixing. The formulation and all process parameters of Comparative Example 312 are also the same as those of Example 301, but the electron beam irradiation device is not used during mixing, and the UV irradiation device and process conditions in Example 201 are used for irradiation.

[0092] 2 g of the sample of each embodiment and comparative example was taken and placed in a mixed solvent of 10 g of cyclohexanone and tetrahydrofuran. The ratio of methyl isobutyl ketone to tetrahydrofuran in the mixed solvent was 8:2. The mixture was placed at room temperature for 48 hours, and the dissolution of the sample in the mixed solvent was observed with the naked eye to observe whether microgel was generated.

[0093] Table 3. Physical properties of materials obtained by different methods

[0094]

[0095] As can be seen from Table 3, the samples obtained in Examples 301 and 302 all contain microgels that are not dissolved by the mixed solvent. These microgels are the result of the shear dispersion and dynamic vulcanization of the nitrile rubber in the samples. In the samples obtained in Examples 301 and 302, the soft PVC is a continuous phase that can flow thermoplastically, and the NBR is a cross-linked dispersed phase.

[0096] The samples obtained in Comparative Examples 311 and 312 were completely dissolved in the mixed solvent and did not contain microgel.

[0097] Comparing the test results of Example 301 and Comparative Example 311 in Table 3, it can be found that the PVC thermoplastic elastomer prepared by the method of dynamic vulcanization caused by electron beam radiation has a lower compression study deformation. The test results of Example 302 show that this PVC thermoplastic elastomer has good thermoplasticity and repeated processing performance. The results of Comparative Example 313 show that the blend of soft PVC and NBR does not undergo crosslinking reaction when irradiated with UV light.

[0098] The present invention is not limited to the embodiments herein. Any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the protection scope of the present invention.

Claims

1. A dynamic radiation cured polymer alloy, characterized in that The dynamic radiation-cured polymer alloy is prepared by dynamic radiation curing of a thermoplastic resin and a radiation-curable composition. In parts by weight, the dynamic radiation-cured polymer alloy consists of 10-98 parts of a thermoplastic resin as a continuous phase, 2-90 parts of a cross-linked radiation-curable composition as a dispersed phase, and 0-15 parts of an additive.

2. The dynamically radiation cured polymer alloy according to claim 1, characterized in that: The radiation curable composition is one of a photocurable composition, an electron beam curable composition, a radiation curable rubber or a rubber compound; The photocurable composition is composed of a photocurable oligomer and a photoinitiator, or is composed of a photocurable oligomer, a photocurable monomer and a photoinitiator, or is composed of a photocurable oligomer, a photocurable monomer, a photoinitiator, and one or more of a co-initiator, a solvent, a reactive diluent, a compatibilizer, a plasticizer, a light stabilizer, a heat stabilizer, an antioxidant, a solid pigment, a color paste, a filler, a defoamer, a coupling agent, a leveling agent, a wetting dispersant and a compatibilizer; The electron beam curable composition is composed of an electron beam curable oligomer, or is composed of an electron beam curable oligomer and one or more selected from an electron beam curable monomer, a sensitizer, a reactive diluent, a solvent, a plasticizer, a light stabilizer, a heat stabilizer, a solid pigment, a color paste, a filler, a defoamer, a coupling agent, a leveling agent, a wetting dispersant and a compatibilizer; The rubber or rubber compound is a rubber containing unsaturated bonds or a rubber compound that can be radiation-cured.

3. The dynamically radiation cured polymer alloy according to claim 1, characterized in that: The radiation curable composition contains, in parts by weight, 100 parts of radiation curable oligomer, 0-10 parts of initiator, 0-100 parts of radiation curable monomer, 0-10 parts of co-initiator, 0-10 parts of sensitizer, 0-100 parts of solvent, 0-100 parts of reactive diluent, 0-50 parts of plasticizer, 0-5 parts of solid pigment, 0-5 parts of color paste, 0-75 parts of filler, 0-2.5 parts of coupling agent, 0-2.5 parts of defoamer, 0-2.5 parts of leveling agent, 0-2.5 parts of wetting dispersant and 0-10 parts of adhesion promoter; The radiation-curable oligomer is one or more of radiation-curable pure acrylate polymers, polyurethane acrylates, polyurethane methacrylates, unsaturated polyesters, epoxy acrylates, epoxy methacrylates, polyester acrylates, polyether acrylates, silicone acrylate polymers, epoxy resins, water-based radiation-curable oligomers, rubbers containing unsaturated bonds, or a mixture of the above oligomers and active solvents or radiation-curable monomers; The reactive solvent, reactive diluent or radiation curable monomer is a monofunctional, difunctional, trifunctional or high-functional monomer, or a mixture of these monomers; The radiation curable composition contains at least one bifunctional, trifunctional or multifunctional radiation curable oligomer, or at least one bifunctional, trifunctional or multifunctional radiation curable monomer; The initiator is a photoinitiator, and the photoinitiator is selected from one or a combination of two or more of benzophenone, 1-hydroxy-cyclohexyl-phenyl ketone, benzoin dimethyl ether, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and isopropylthiophenone; the photoinitiator is a single photoinitiator, or is composed of two or more photoinitiators; The auxiliary initiator is selected from one or more compounds prepared by Michael addition reaction of triethylamine, diethanolamine, N-methylethanolamine, N,N-dimethylethanolamine, N,N-diethylethanolamine, ethyl 4-dimethylaminobenzoate, diethylamine or diethanolamine with difunctional acrylate or multifunctional acrylate; The sensitizer is selected from one or two of a trifunctional unsaturated polyester monomer, a tetrafunctional unsaturated polyester monomer, a pentafunctional unsaturated polyester monomer, or a hexafunctional unsaturated polyester monomer; The solvent is alcohol, ester, ketone, aromatic hydrocarbon, alcohol ether, ether ester solvent, dimethyl sulfoxide, N,N-dimethylformamide, dimethyl carbonate, nitromethane, nitroethane, 1-nitropropane or water with a boiling point below 200° C. under normal pressure and without polymerization or cross-linking ability; The plasticizer is a phthalate ester, phosphate ester, polyol ester, dibasic fatty acid ester, epoxy, citrate compound or polymeric plasticizer having a boiling point higher than 250° C. at normal pressure; The solid pigment is a solid inorganic pigment, an organic pigment or a mixture thereof; The color paste is a concentrate containing a solid pigment dispersed in a solvent or resin and a small amount of an active agent; The filler is an inorganic filler or an organic filler; the inorganic filler is calcium carbonate, calcium sulfate, talcum powder, kaolin, microsilica powder, diatomaceous earth or white carbon black, and the organic filler is nanocellulose, silicone resin powder or rubber powder; The coupling agent is a silane coupling agent, a titanate coupling agent, an aluminate coupling agent, a bimetallic coupling agent, a phosphate coupling agent, a borate coupling agent or a chromium complex coupling agent.

4. The dynamically radiation cured polymer alloy according to claim 1, characterized in that: The dynamic radiation-cured polymer alloy may contain 0.2wt%-10wt% of a polymer compatibilizer; the polymer compatibilizer includes maleic anhydride, acrylic acid or glycidyl methacrylate grafted polyolefin or polyolefin elastomer, block copolymer of polysiloxane and polycarbonate, styrene-maleic anhydride copolymer and styrene-acrylonitrile-glycidyl methacrylate copolymer.

5. The dynamically radiation cured polymer alloy according to claim 1, characterized in that: The radiation curable composition is in the form of liquid, paste or raw rubber.

6. The dynamically radiation cured polymer alloy according to claim 1, characterized in that: The thermoplastic resin is selected from one of polyethylene, polypropylene, polyvinyl chloride, chlorinated polyvinyl chloride, chlorinated polyethylene, polystyrene, polymethyl methacrylate, polyamide, polycarbonate, polyester, polyacrylic acid, acrylonitrile-styrene-butadiene polymer, acrylonitrile-styrene polymer, polyurethane, polyoxymethylene, polyphenylene ether, polysulfone, polyethersulfone, polyphenylene sulfide, polyaryletherketone resin, a blend of one of them, or a chemically modified product of one of them, or is selected from one of urethane, ester, amide, olefin, ethylene, styrene, diene, vinyl chloride, silicone, and organic fluorine thermoplastic elastomers; the thermoplastic resin is a transparent, translucent or opaque single-component thermoplastic resin or a thermoplastic resin containing the above thermoplastic resin. a thermoplastic resin containing a flame retardant, an antioxidant, a light stabilizer, a heat stabilizer, a foaming agent, a colorant, a plasticizer, a lubricant, an impact resistant agent, an antibacterial agent, an antistatic agent or a conductive filler, or a thermoplastic resin containing a cheap filler, wherein the cheap filler is calcium carbonate, magnesium carbonate, dolomite, kaolin, diatomaceous earth, mica powder, calcium silicate, wollastonite, quartz powder, glass powder, glass microbeads, attapulgite, zeolite, talc, montmorillonite, bentonite, asbestos, barium sulfate, calcium sulfate, calcium sulfite, graphite, carbon black, white carbon black, aluminum oxide, magnesium oxide, titanium dioxide, zinc oxide, iron oxide, aluminum hydroxide or magnesium hydroxide; The thermoplastic resin is the genuine material, secondary material, sprue material or recycled material of the thermoplastic resin; the genuine material is the material produced by the thermoplastic resin factory and meets various quality inspection standards; the secondary material refers to the material that does not meet various quality inspection standards when leaving the factory but is still useful compared to the genuine material; the sprue material refers to the material left in the gate and runner parts of the thermoplastic resin during the injection molding process in order to form a product; the recycled material refers to the material that is recycled after the thermoplastic resin is formed into a product and used.

7. A method for preparing a dynamically radiation cured polymer alloy according to any one of claims 1 to 6, characterized in that: The preparation method comprises the following steps: Step A, weighing the raw materials according to the weight ratio of claims 1 to 6, mixing them evenly to prepare a radiation curable composition; or, purchasing the radiation curable composition from the market according to the weight ratio of claims 1 to 6; Step B, uniformly mixing the radiation curable composition obtained in step A and a thermoplastic resin using a mixing device; the mixing device is an open mixer, a kneading mill, a internal mixer, a screw granulator, an extruder, a calender or an injection molding machine; Step C, continuing the mixing operation, while turning on UV light or electron beam radiation to irradiate the mixed materials, so that the radiation-curable composition in the materials undergoes a radiation curing reaction, thereby obtaining a dynamic radiation-cured polymer alloy; Step D, pelletizing the material extruded by the screw granulator in step C to obtain a dynamic radiation-cured polymer alloy pellet with a weight of less than or equal to 1.0 g per pellet; or cutting, chopping, grinding, tearing or crushing the material obtained by an open mill, kneading mill, internal mixer, extruder, calender or injection molding machine in step C with a pulverizer to obtain a granular dynamic radiation-cured polymer alloy; or further granulating the obtained granular dynamic radiation-cured polymer alloy with a screw granulator to prepare a dynamic radiation-cured polymer alloy pellet with a weight of less than or equal to 1.0 g per pellet; Step E: Processing the material obtained by the extruder in step C into an extruded product of a dynamic radiation-cured polymer alloy; processing the material obtained by the injection molding machine in step C into an injection molded part of a dynamic radiation-cured polymer alloy; or, further thermoplastic processing the material obtained in step D to obtain an injection molded product, an extruded product or a calendered product.

8. The method for preparing a dynamically radiation cured polymer alloy according to claim 7, characterized in that: Step B and step C in claim 7 are carried out once or multiple times, wherein the mixing equipment used is one or more of an open mixer, a kneading mill, an internal mixer, a screw granulator, an extruder, a calender or an injection molding machine.

9. The method for preparing a dynamically radiation cured polymer alloy according to claim 7, characterized in that: The UV light source used for radiation curing is a mercury lamp, an electrodeless lamp, a metal halide lamp or an LED lamp; or the electron beam used for radiation curing is a low-energy electron beam, a medium-energy electron beam or a high-energy electron beam.

10. A dynamically radiation cured polymer alloy according to any one of claims 1 to 6, characterized in that: The dynamically radiation cured polymer alloy is a thermoplastic elastomer, a toughened plastic or a reinforced plastic.

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