Preparation method of anti-aging agent and application of anti-aging agent in plastics

Abstract

The invention relates to the technical field of anti-aging agents, and discloses a preparation method of an anti-aging agent and application of the anti-aging agent in plastics, the anti-aging agent contains styrene groups, and can be well fused and grafted with polyolefin such as polypropylene under the action of an initiator dibenzoyl peroxide or dicumyl peroxide, so that the anti-aging agent has a good anti-aging effect. The influence on the mechanical strength of the polyolefin plastic is very small, and the problem that physical blending can cause great influence on the mechanical strength and the use performance of the plastic can be avoided. Meanwhile, a phenol triazine structure contained in the anti-aging agent has a unique ultraviolet absorption effect, and a hindered amine structure is contained, so that the photo-oxygen degradation reaction of the polyolefin plastic can be inhibited through multiple ways of capturing free radicals and decomposing hydroperoxide, and through an accelerated aging experiment of xenon lamp irradiation, the plastic keeps very high tensile strength, and the anti-aging effect is good. And excellent thermo-oxidative aging resistance and ultraviolet radiation aging resistance are shown.

Description

Technical Field

[0001] The present invention relates to the technical field of anti-aging agents, and specifically to a preparation method of an anti-aging agent and its application in plastics. Background Art

[0002] Polyolefin plastics mainly include polyethylene, polyvinyl chloride, polypropylene, polystyrene, etc. They have good chemical resistance, electrical insulation, and excellent high-strength mechanical properties, and are widely used. However, polyolefin plastics such as polyvinyl chloride and polypropylene have poor thermal-oxidative aging resistance and ultraviolet aging resistance. After long-term heat treatment or light exposure, their properties will be affected.

[0003] Usually, antioxidants, ultraviolet absorbers, etc. are added during the processing of polyolefins to improve the thermal-oxidative aging resistance, ultraviolet aging resistance, etc. of polyolefins. Currently, the main anti-aging agents include phosphite antioxidants, hindered amine light stabilizers, benzophenone ultraviolet absorbers, and triazine ultraviolet absorbers. Developing new bifunctional anti-aging agents for application in polyolefin plastics is a research hotspot.

[0004] The patent with the publication number CN109134928B discloses an N-substituted triazine hindered amine light stabilizer, which can be used as a stabilizer for organic substances sensitive to degradation caused by light, heat, or oxidation and a flame retardant for organic substances. The patent with the publication number CN110724165B discloses a hexahydrotriazine compound with thermal-oxidative resistance. The molecular structure of this aging resistance agent contains a large number of benzene rings, hindered phenols, triazine ring structures, etc., which can improve the aging resistance of polyvinyl chloride. However, directly physically blending antioxidants, ultraviolet absorbers, anti-aging agents with polyolefin plastics such as polypropylene and polyvinyl chloride will result in poor compatibility between the anti-aging agents and the matrix, which will affect the mechanical strength and service performance of the plastics, and there will also be a phenomenon of precipitation and migration of antioxidants and anti-aging agents. Summary of the Invention

[0005] The present invention solves the following technical problems: It provides a preparation method of a bifunctional anti-aging agent, which solves the problem of poor anti-aging performance of polyolefin plastics such as polypropylene.

[0006] The present invention provides the following technical solution:

[0007] A preparation method of an anti-aging agent, the structural formula of the anti-aging agent is shown as formula (Ⅰ);

[0008]

[0009] The preparation method is as follows:

[0010] S1. At -5 to 0 °C, add a solvent, 2-amino-4,6-dichlorotriazine, 4-vinylbenzoyl chloride, and the catalyst pyridine to a flask, react at 15 - 25 °C for 3 - 6 h, after the reaction, concentrate by rotary evaporation, wash with n-hexane, and dry to obtain Intermediate 1;

[0011] S2. Add chloroform solvent, Intermediate 1, 2,4-dihydroxytoluene, and the catalyst aluminum trichloride to a flask, after the reaction, concentrate by rotary evaporation, wash successively with saturated sodium chloride solution and acetone, and dry to obtain Intermediate 2;

[0012] S3. Add n-butanol solvent, aqueous formaldehyde solution, Intermediate 2, and 2,2,6,6-tetramethylpiperidinamine to a flask, after the reaction, concentrate by rotary evaporation, add water and ethyl acetate, extract and separate, concentrate the organic layer by rotary evaporation, wash with acetone, and recrystallize the product with a mixed solution of ethanol and ethyl acetate with a volume ratio of 1:1 to obtain the anti-aging agent.

[0013] Further, the solvent in S1 includes ethyl acetate, 1,4-dioxane, acetone, and tetrahydrofuran.

[0014] Further, the ratio of 2-amino-4,6-dichlorotriazine, 4-vinylbenzoyl chloride, and pyridine in S1 is 1 mol:(2 - 2.2) mol:(2 - 2.4) mol.

[0015] Further, the ratio of Intermediate 1, 2,4-dihydroxytoluene, and aluminum trichloride in S2 is 1 mol:(3.6 - 4.8) mol:(3.5 - 4.5) mol.

[0016] Further, the reaction temperature in S2 is 20 - 35 °C, and the reaction time is 6 - 12 h.

[0017] Further, the ratio of formaldehyde, Intermediate 2, and 2,2,6,6-tetramethylpiperidinamine in S3 is (6 - 7.2):1 mol:(2.6 - 3.5) mol.

[0018] Further, the reaction temperature in S3 is 85 - 100 °C, and the reaction time is 10 - 18 h.

[0019] Further, place polyolefin, anti-aging agent, and the initiator dibenzoyl peroxide or diisopropylbenzene peroxide in a twin-screw extruder for melt grafting, the temperature of each section of the extruder is 180 - 210 °C, the screw speed is 100 - 150 r / min, extrude, then dissolve the material in xylene, add acetone for precipitation, filter, wash with acetone, and dry to obtain the anti-aging plastic.

[0020] Further, the ratio of polyolefin, anti-aging agent, and initiator is 1 g:(1 - 6) mg:(0.3 - 3) mg.

[0021] Furthermore, the polyolefin includes polyethylene, polyvinyl chloride, polypropylene, polystyrene, ethylene-vinyl acetate copolymer, acrylonitrile-butadiene-styrene copolymer.

[0022] The technical effects produced by the present invention are as follows:

[0023] Using 2-amino-4,6-dichlorotriazine, 4-vinylbenzoyl chloride, 2,2,6,6-tetramethylpiperidineamine, 2,4-dihydroxytoluene, etc. as reaction raw materials, through esterification reaction, Friedel-Crafts reaction and Mannich reaction, a novel anti-aging agent is prepared, which has the advantages of novel and efficient preparation method, simple operation, high yield of the product and novel structure. Using 2,4-dihydroxytoluene as a raw material, a methyl group is introduced at the 3-position of the benzene ring, and intermediate 2 is obtained by reaction, which can avoid the reaction of 2,2,6,6-tetramethylpiperidineamine with the carbon atom at the 3-position of its benzene ring in the subsequent reaction, reduce the complexity of the reaction system, and thus obtain an anti-aging agent product with high yield.

[0024] The anti-aging agent prepared by the present invention contains a styrene group, and under the action of initiator dibenzoyl peroxide or diisopropylbenzene peroxide, it can be well melt-grafted with polyolefins such as polypropylene and polyethylene, and has little influence on the mechanical strength of polyolefin plastics such as polypropylene and polyethylene, which can avoid the problem that physical blending will have a greater impact on the mechanical strength and service performance of polyolefin plastics such as polypropylene and polyethylene. At the same time, the structure of phenol-based triazine contained in the anti-aging agent has a unique ultraviolet absorption effect and contains a hindered amine structure, and can inhibit the photo-oxidative degradation reaction of plastics such as polypropylene and polyethylene by various ways such as capturing free radicals and decomposing hydroperoxides. After the xenon lamp irradiation accelerated aging experiment, plastics such as polypropylene and polyethylene maintain a very high tensile strength and show excellent thermal-oxidative aging resistance and ultraviolet irradiation aging resistance. The anti-aging agent prepared by the present invention has broad application prospects in the field of polyolefin plastics. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is the preparation route of the anti-aging agent.

[0026] Figure 2 is the infrared spectrum of the anti-aging agent. DETAILED DESCRIPTION OF THE INVENTION

[0027] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

[0028] Polyolefin, antioxidant, benzoyl peroxide or diisopropylbenzene peroxide initiator are placed in a twin-screw extruder in a ratio of 1 g:(1 - 6) mg:(0.3 - 3) mg for melt grafting. The polyolefin includes polyethylene, polyvinyl chloride, polypropylene, polystyrene, ethylene-vinyl acetate copolymer, acrylonitrile-butadiene-styrene copolymer; the temperature of each section of the extruder is 180 - 210 °C, the screw speed is 100 - 150 r / min, and then extruded. Then the material is dissolved in xylene, acetone is added for precipitation, filtered, washed with acetone, and dried to obtain the anti-aging plastic.

[0029] Example 1

[0030] At 0 °C, 20 mL of acetone solvent, 6 mmol of 2-amino-4,6-dichlorotriazine, 12 mmol of 4-vinylbenzoyl chloride and 12 mmol of catalyst pyridine are added to a flask, and the reaction is carried out at 25 °C for 3 h. After the reaction, it is rotary evaporated and concentrated, washed with n-hexane, and dried to obtain Intermediate 1. The theoretical yield is 1.77 g (6 mmol), the actual yield is 1.47 g, and the yield is 83.1%.

[0031] 10 mL of chloroform solvent, 4 mmol of Intermediate 1, 14.4 mmol of 2,4-dihydroxytoluene, and 14 mmol of catalyst aluminum trichloride are added to a flask, and the reaction is carried out at 25 °C for 10 h. After the reaction, it is rotary evaporated and concentrated, washed successively with saturated sodium chloride solution and acetone, and dried to obtain Intermediate 2. The theoretical yield is 1.88 g (4 mmol), the actual yield is 1.70 g, and the yield is 90.4%.

[0032] 10 mL of n-butanol solvent, an aqueous solution containing 24 mmol of formaldehyde, 4 mmol of Intermediate 2 and 10.4 mmol of 2,2,6,6-tetramethylpiperidineamine are added to a flask, and the reaction is carried out at 100 °C for 10 h. After the reaction, it is rotary evaporated and concentrated, water and ethyl acetate are added for extraction and separation, the organic layer is rotary evaporated and concentrated, washed with acetone, and the product is recrystallized with a mixed solution of ethanol and ethyl acetate with a volume ratio of 1:1 to obtain the antioxidant. The theoretical yield is 3.11 g (4 mmol), the actual yield is 1.81 g, and the yield is 58.2%.

[0033] Specification Figure 2 The infrared spectrum of the antioxidant shows that: 3384 cm -1 is the absorption peak of the secondary amine bond N-H; 1561 cm -1 and 1492 cm -1 are the absorption peaks of the C=N bond and C=C bond in the triazine ring respectively; 1361 cm -1 and 1198 cm -1 are the out-of-plane vibration peak and contraction vibration peak of the phenolic hydroxyl group respectively.

[0034] Example 2

[0035] At -5°C, 25 mL of ethyl acetate solvent, 6 mmol of 2-amino-4,6-dichlorotriazine, 12.6 mmol of 4-vinylbenzoyl chloride, and 13 mmol of catalyst pyridine were added to a flask, and the reaction was carried out at 15°C for 6 h. After the reaction, it was concentrated by rotary evaporation, washed with n-hexane, and dried to obtain Intermediate 1. The theoretical yield was 1.77 g (6 mmol), the actual yield was 1.64 g, and the yield was 92.7%.

[0036] 10 mL of chloroform solvent, 4 mmol of Intermediate 1, 16.8 mmol of 2,4-dihydroxytoluene, and 16 mmol of catalyst aluminum trichloride were added to a flask, and the reaction was carried out at 35°C for 6 h. After the reaction, it was concentrated by rotary evaporation, washed successively with saturated sodium chloride solution and acetone, and dried to obtain Intermediate 2. The theoretical yield was 1.88 g (4 mmol), the actual yield was 1.79 g, and the yield was 95.2%.

[0037] 15 mL of n-butanol solvent, an aqueous solution containing 26.5 mmol of formaldehyde, 4 mmol of Intermediate 2, and 12.5 mmol of 2,2,6,6-tetramethylpiperidineamine were added to a flask, and the reaction was carried out at 90°C for 12 h. After the reaction, it was concentrated by rotary evaporation, water and ethyl acetate were added, and extraction and separation were carried out. The organic layer was concentrated by rotary evaporation, washed with acetone, and the product was recrystallized with a mixed solution of ethanol and ethyl acetate with a volume ratio of 1:1 to obtain the anti-aging agent. The theoretical yield was 3.11 g (4 mmol), the actual yield was 2.19 g, and the yield was 70.4%.

[0038] Example 3

[0039] At 0°C, 30 mL of tetrahydrofuran solvent, 6 mmol of 2-amino-4,6-dichlorotriazine, 13.2 mmol of 4-vinylbenzoyl chloride, and 14.4 mmol of catalyst pyridine were added to a flask, and the reaction was carried out at 20°C for 4 h. After the reaction, it was concentrated by rotary evaporation, washed with n-hexane, and dried to obtain Intermediate 1. The theoretical yield was 1.77 g (6 mmol), the actual yield was 1.58 g, and the yield was 89.3%.

[0040] 15 mL of chloroform solvent, 4 mmol of Intermediate 1, 19.2 mmol of 2,4-dihydroxytoluene, and 18 mmol of catalyst aluminum trichloride were added to a flask, and the reaction was carried out at 20°C for 12 h. After the reaction, it was concentrated by rotary evaporation, washed successively with saturated sodium chloride solution and acetone, and dried to obtain Intermediate 2. The theoretical yield was 1.88 g (4 mmol), the actual yield was 1.81 g, and the yield was 96.3%.

[0041] Add 20 mL of n-butanol solvent, an aqueous solution containing 28.8 mmol of formaldehyde, 4 mmol of intermediate 2, and 14 mmol of 2,2,6,6-tetramethylpiperidineamine to a flask, react at 85 °C for 18 h. After the reaction, concentrate by rotary evaporation, add water and ethyl acetate, extract and separate. Concentrate the organic layer by rotary evaporation, wash with acetone, and recrystallize the product with a mixed solution of ethanol and ethyl acetate with a volume ratio of 1:1 to obtain the anti-aging agent. The theoretical yield is 3.11 g (4 mmol), the actual yield is 2.09 g, and the yield is 67.2%.

[0042] Example 4

[0043] Place 100 g of polypropylene resin, 0.1 g of anti-aging agent (prepared in the same way as in Example 2), and 0.03 g of initiator diisopropylbenzene peroxide in a twin-screw extruder for melt grafting. The temperatures of the 1st - 5th sections of the extruder are 180, 195, 210, 210, 210 °C respectively, the screw speed is 120 r / min, extrude, then dissolve the material in xylene, add acetone for precipitation, filter, wash with acetone, and dry to obtain the anti-aging polypropylene plastic.

[0044] Example 5

[0045] The difference between this example and Example 4 is that the initiator is 0.03 g of benzoyl peroxide, and the anti-aging polypropylene plastic is obtained.

[0046] Example 6

[0047] The difference between this example and Example 4 is that the dosage of the anti-aging agent is 0.4 g and the dosage of the initiator diisopropylbenzene peroxide is 0.17 g, and the anti-aging polypropylene plastic is obtained.

[0048] Example 7

[0049] The difference between this example and Example 4 is that the dosage of the anti-aging agent is 0.6 g and the dosage of the initiator diisopropylbenzene peroxide is 0.3 g, and the anti-aging polypropylene plastic is obtained.

[0050] Comparative Example 1 is pure polypropylene resin.

[0051] Comparative Example 2

[0052] Place 100 g of polypropylene resin and 0.1 g of anti-aging agent (prepared in the same way as in Example 2) in a twin-screw extruder for melt blending. The temperatures of the 1st - 5th sections of the extruder are 180, 195, 210, 210, 210 °C respectively, the screw speed is 120 r / min, extrude to obtain polypropylene plastic.

[0053] Comparative Example 3

[0054] 100 g of polypropylene resin and 0.1 g of 2,2,6,6-tetramethylpiperidineamine were placed in a twin-screw extruder for melt blending. The temperatures of the 1st - 5th sections of the extruder were 180, 195, 210, 210, and 210 °C respectively, the screw speed was 120 r / min, and extrusion was carried out to obtain polypropylene plastic.

[0055] The polypropylene plastics of Examples 4 - 7 and Comparative Examples 2 - 3, as well as the pure polypropylene resin of Comparative Example 1, were placed in a flat vulcanizing machine and molded at 10 MPa and 200 °C for 6 min; according to the method of GB / T 1622.2 - 2014, xenon lamp aging experiments were carried out in an accelerated aging test chamber, controlling the xenon lamp power at 600 W, the temperature at 65 °C, the relative humidity at 65%, and the aging times were 0, 24 h, 48 h, 96 h, 192 h, and 384 h respectively.

[0056] The tensile properties of the polypropylene plastic were tested according to the method of GB / T 1040.2 - 2006.

[0057]

[0058]

[0059] In Examples 4 and 5, benzoyl peroxide or diisopropylbenzene peroxide was used to melt-graft the prepared anti-aging agent with polypropylene. Compared with the tensile strength (36.7 MPa) of the pure polypropylene in Comparative Example 1, there was almost no difference in the tensile strength of Examples 4 and 5, indicating that after grafting the anti-aging agent, it had no effect on the mechanical properties of polypropylene. At the same time, the structure of the phenol-based triazine contained in the anti-aging agent has a unique ultraviolet absorption effect and contains a hindered amine structure, and can inhibit the photo-oxidative degradation reaction of polypropylene through multiple ways such as capturing free radicals and decomposing hydroperoxides. After 384 h of xenon lamp ultraviolet irradiation, the retention rate of its tensile strength reached more than 96%.

[0060] In Examples 6 and 7, as the amount of the anti-aging agent increased, the initial tensile strength (xenon lamp irradiation for 0 h) of polypropylene showed a downward trend, but after xenon lamp ultraviolet irradiation, its retention rate gradually increased, reaching a maximum of 97.7%.

[0061] Comparative Example 1 was pure polypropylene with an initial tensile strength of 36.7 MPa. After 384 h of xenon lamp ultraviolet irradiation, its tensile strength was 25.1 MPa, and the retention rate was only 68.4%, showing the worst anti-aging performance.

[0062] Comparative Example 2 The prepared anti-aging agent was physically blended with polypropylene. The initial tensile strength of polypropylene was 32.7 MPa, significantly lower than that of Example 3 (36.4 MPa), probably because the compatibility between the anti-aging agent and polypropylene was poor, and the mechanical properties of polypropylene plastics would be affected after physical blending.

[0063] Comparative Example 3 2,2,6,6-Tetramethylpiperidineamine was added as a light stabilizer, which did not contain the ultraviolet-resistant structure of phenol-based triazine and had poor ultraviolet aging resistance. After 384 h of xenon lamp ultraviolet irradiation, the tensile strength of the polypropylene plastic was 28.6 MPa, and the retention rate was only 81.2%.

[0064] Example 8

[0065] 100 g of polyethylene resin, 0.4 g of anti-aging agent (prepared in the same way as in Example 2), and 0.17 g of initiator dicumyl peroxide were placed in a twin-screw extruder for melt grafting. The temperatures of the 1st - 5th sections of the extruder were 180, 190, 205, 205, and 200 °C respectively, the screw speed was 100 r / min, and then extrusion was carried out. Then the material was dissolved in xylene, acetone was added for precipitation, filtration was carried out, and then washing with acetone and drying were carried out to obtain anti-aging polyethylene plastic.

[0066] Comparative Example 4

[0067] 100 g of polyethylene resin and 0.4 g of anti-aging agent (prepared in the same way as in Example 2) were placed in a twin-screw extruder for melt grafting. The temperatures of the 1st - 5th sections of the extruder were 180, 190, 205, 205, and 200 °C respectively, the screw speed was 100 r / min, and then extrusion was carried out to obtain polyethylene plastic.

[0068] Comparative Example 5 was pure polyethylene resin.

[0069] The polyethylene plastics of Example 8 and Comparative Example 4, and the pure polyethylene resin of Comparative Example 5 were respectively placed in a flat vulcanizing machine, and molded at 10 MPa and 200 °C for 5 min; according to the method of GB / T 1622.2 - 2014, xenon lamp aging experiments were carried out in an accelerated aging test chamber, controlling the xenon lamp power at 600 W, the temperature at 65 °C, the relative humidity at 65%, and the aging times were 0, 24 h, 48 h, 96 h, 192 h, and 384 h respectively.

[0070] The tensile properties of the polyethylene plastics were tested according to the method of GB / T 1040.2 - 2006.

[0071]

[0072] Example 8: The polyethylene resin was melt grafted with an antioxidant. After 384 h of xenon lamp ultraviolet irradiation, the tensile strength retention rate of the polyethylene plastic reached 96.9%.

[0073] Comparative Example 4: The antioxidant was physically blended with the polyethylene resin, and the initial tensile strength of the polyethylene plastic was only 27.1 MPa.

[0074] Comparative Example 5: The pure polyethylene resin was irradiated with a xenon lamp ultraviolet for 384 h, and the tensile strength retention rate was only 70.2%.

Claims

1. A method for preparing an anti-aging agent, characterized in that, The structural formula of the anti-aging agent is shown in Formula (Ⅰ); The preparation method is as follows: S1. At -5 to 0 °C, add a solvent, 2-amino-4,6-dichlorotriazine, 4-vinylbenzoyl chloride, and the catalyst pyridine to a flask, react at 15 - 25 °C for 3 - 6 h, after the reaction, concentrate by rotary evaporation, wash with n-hexane, and dry to obtain Intermediate 1; S2. Add chloroform solvent, Intermediate 1, 2,4-dihydroxytoluene, and the catalyst aluminum trichloride to a flask, after the reaction, concentrate by rotary evaporation, wash successively with saturated sodium chloride solution and acetone, and dry to obtain Intermediate 2; S3. Add n-butanol solvent, aqueous formaldehyde solution, Intermediate 2, and 2,2,6,6-tetramethylpiperidinamine to a flask, after the reaction, concentrate by rotary evaporation, add water and ethyl acetate, extract and separate, concentrate the organic layer by rotary evaporation, wash with acetone, and recrystallize the product with a mixed solution of ethanol and ethyl acetate with a volume ratio of 1:1 to obtain the anti-aging agent.

2. The preparation method of the anti-aging agent according to claim 1, characterized in that, The solvent in S1 includes ethyl acetate, 1,4-dioxane, acetone, and tetrahydrofuran.

3. The preparation method of the anti-aging agent according to claim 1, characterized in that, The ratio of 2-amino-4,6-dichlorotriazine, 4-vinylbenzoyl chloride, and pyridine in S1 is 1 mol:(2 - 2.2) mol:(2 - 2.4) mol.

4. The preparation method of the anti-aging agent according to claim 1, characterized in that, The ratio of Intermediate 1, 2,4-dihydroxytoluene, and aluminum trichloride in S2 is 1 mol:(3.6 - 4.8) mol:(3.5 - 4.5) mol.

5. The preparation method of the anti-aging agent according to claim 1, characterized in that, The reaction temperature in S2 is 20 - 35 °C, and the reaction time is 6 - 12 h.

6. The preparation method of the anti-aging agent according to claim 1, wherein, The ratio of formaldehyde, Intermediate 2, and 2,2,6,6-tetramethylpiperidinamine in S3 is (6 - 7.2):1 mol:(2.6 - 3.5) mol.

7. The preparation method of the anti-aging agent according to claim 1, characterized in that, The reaction temperature in S3 is 85 - 100 °C, and the reaction time is 10 - 18 h.

8. Use of an anti-aging agent prepared by the preparation method according to any one of claims 1-7 in plastics, characterized in that: Place polyolefin, anti-aging agent, and initiator dibenzoyl peroxide or diisopropylbenzene peroxide in a twin-screw extruder for melt grafting. The temperature of each section of the extruder is 180 - 210 °C, the screw speed is 100 - 150 r / min, extrude, then dissolve the material in xylene, add acetone for precipitation, filter, wash with acetone, and dry to obtain the anti-aging plastic.

9. Use of the anti-aging agent according to claim 8 in plastics, characterized in that: The ratio of polyolefin, anti-aging agent, and initiator is 1 g:(1 - 6) mg:(0.3 - 3) mg.

10. The application of the anti-aging agent according to claim 8 in plastics, characterized in that: Polyolefins include polyethylene, polyvinyl chloride, polypropylene, polystyrene, ethylene-vinyl acetate copolymer, and acrylonitrile-butadiene-styrene copolymer.

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