High-strength impact-resistant modified polypropylene plastic and application thereof in durable toys

Abstract

The invention relates to the technical field of polypropylene, and discloses a high-strength impact-resistant modified polypropylene plastic and application thereof in durable toys, the high-strength impact-resistant modified polypropylene plastic comprises 100 parts by weight of polypropylene, 10-30 parts by weight of hyperbranched polyurethane elastomer, 2-8 parts by weight of a filler, and 0.3-0.5 part by weight of an antioxidant; the hyperbranched polyurethane elastomer contains an alkyl long chain with good compatibility with polypropylene, and meanwhile, in the high-temperature melt extrusion process, the alkyl long chain and a polypropylene molecular chain form a physical chain winding effect, so that the compatibility between the polyurethane elastomer and the polypropylene is remarkably improved, and the interfacial force between the polyurethane elastomer and the polypropylene is improved; the hyperbranched polyurethane elastomer has a better toughening effect, and the tensile property, the bending strength and the impact strength are obviously improved.

Description

Technical Field

[0001] The invention relates to the technical field of polypropylene, in particular to a high-strength impact-resistant modified polypropylene plastic and application thereof in durable toys. Background Art

[0002] Polypropylene is non-toxic and odorless, transparent in appearance, light in texture, and has good insulation performance. It is widely used in the fields of toys, household appliances, building materials, medical supplies, etc. It is of great significance to toughen and modify polypropylene and improve its mechanical strength. Usually, inorganic fillers, nanomaterials, rubber elastomers, etc. are added to polypropylene to improve its mechanical properties. Polyurethane is a high-toughness, high-strength polymer resin material that can be made into hyperbranched polymers, elastomeric materials, elastic fibers, etc. It has a good toughening effect on materials such as epoxy resins, polyphenylene sulfide, polyoxymethylene, and polylactic acid. Chinese patent CN116554553B discloses reacting functionalized boron nitride nanosheets, polyester diols, hexamethylene diisocyanate, and chain extenders to obtain P-BNNS modified polyurethane elastomers, which are mixed with polypropylene resins, etc. The obtained polypropylene insulating material has good insulation, flame retardant and other properties. However, the patent does not improve the bending, impact resistance and other properties of polypropylene materials. Summary of the invention

[0003] (I) Technical problems to be solved: In view of the deficiencies of the prior art, the present invention provides a modified polypropylene plastic with good mechanical strength and good impact resistance.

[0004] (II) Technical solution: A high-strength impact-resistant modified polypropylene plastic, comprising 100 parts by weight of polypropylene, 10-30 parts by weight of hyperbranched polyurethane elastomer, 2-8 parts by weight of filler, and 0.3-0.5 parts by weight of antioxidant.

[0005] The preparation method of the hyperbranched polyurethane elastomer is as follows: add dry polytetramethylene glycol, diisocyanate monomer, and dibutyltin dilaurate into a reaction container, introduce nitrogen, heat to 80-90° C., react for 2-3 hours, and then react with a general structural formula The mixture is mixed with a chain extender, wherein n is any integer between 12 and 20, poured into a mold at a temperature of 100° C., first reacted at 90-100° C. for 1.5-2 hours, then reacted at 110-120° C. for 4-5 hours, cooled and discharged to obtain a hyperbranched polyurethane elastomer.

[0006] The preparation method of high-strength impact-resistant modified polypropylene plastic is as follows: polypropylene, hyperbranched polyurethane elastomer, filler and antioxidant are mixed in a mixer, and then the mixture is extruded and pelletized through a twin-screw extruder with a 1-6 section temperature of 150-185°C and a screw speed of 100-200 r / min to obtain high-strength impact-resistant modified polypropylene plastic.

[0007] Furthermore, the filler includes any one of talc, calcium carbonate, and glass microspheres.

[0008] Furthermore, the antioxidant includes any one of antioxidant 1010 , antioxidant 1076 , and antioxidant 168 .

[0009] Furthermore, the molar ratio of polytetramethylene glycol, diisocyanate monomer and chain extender is 1:(2.6-3):(1.2-1.6). The diisocyanate monomer includes any one of toluene-2,4-isocyanate and diphenylmethane-4,4'-diisocyanate.

[0010] Further, the preparation method of the chain extender is:

[0011] (1) Add ethanol, terephthalaldehyde and 2-amino-1,3-propanediol in a molar ratio of 1:(2-2.2) to a reaction vessel, heat to 70-80°C, react for 18-24 hours, condense and reflux during the reaction, cool to room temperature, add sodium borohydride, react for 4-6 hours, remove ethanol by rotary evaporation, separate and purify by silica gel column, and obtain terephthalimino-1,3-propanediol. The preparation reaction formula is:

[0012]

[0013] (2) Add ethanol, p-terephthalimino-1,3-propanediol and 1-bromoalkane in a molar ratio of 1:(2.2-2.4) to a reaction vessel, heat to 70-80°C, react for 12-18 hours, condense and reflux during the reaction, remove ethanol by rotary evaporation, wash with water, and separate and purify by silica gel column to obtain a chain extender. The structural formula of 1-bromoalkane is Br-C n H 2n+1 , n is any integer between 12 and 20. The preparation reaction formula is:

[0014]

[0015] Furthermore, high-strength impact-resistant modified polypropylene plastics are used in durable toys.

[0016] (III) Technical Effect: A chain extender containing multiple hydroxyl groups and alkyl long chains was prepared using cheap and readily available terephthalaldehyde, 2-amino-1,3-propanediol, and 1-bromoalkane as reactants, which were then copolymerized and chain extended with diisocyanate monomers and polytetramethylene glycol to obtain a hyperbranched polyurethane elastomer. Finally, it was melt-extruded with fillers such as polypropylene and calcium carbonate to obtain a high-strength impact-resistant modified polypropylene plastic.

[0017] The hyperbranched polyurethane elastomer of the invention contains an alkyl long chain with good compatibility with polypropylene. Simultaneously, in the process of high-temperature melt extrusion, the alkyl long chain and the polypropylene molecular chain form a physical chain entanglement effect, which significantly improves the compatibility between the polyurethane elastomer and the polypropylene, increases the interface force between the two, and enables the hyperbranched polyurethane elastomer to have a better toughening effect, and the tensile property, bending strength and impact strength are significantly improved. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] The polypropylene in the embodiment of the present invention is of grade K7726, produced by Shanghai Qianfu Industrial Co., Ltd. Glass microspheres, model 3M hollow glass microspheres VS5500, produced by Shanghai Waidian International Trade Co., Ltd. Calcium carbonate, average particle size 2000 mesh Talc, average particle size 600 mesh.

[0020] Embodiment 1:

[0021] (1) Add 300 mL of ethanol, 60 mmol of terephthalaldehyde, and 132 mmol of 2-amino-1,3-propanediol to a reaction container, heat to 80° C., react for 18 h, condense and reflux during the reaction, cool to room temperature, add 144 mmol of sodium borohydride, react for 6 h, remove ethanol by rotary evaporation, and separate and purify by silica gel column to obtain terephthalimino-1,3-propanediol.

[0022] (2) Add 250 mL of ethanol, 50 mmol of 1,3-diol, and 116 mmol of 1-bromooctadecane to a reaction container, heat to 70° C., and react for 18 h. During the reaction, condense and reflux, and remove ethanol by rotary evaporation. After washing with water, separate and purify on a silica gel column to obtain a chain extender.

[0023] (3) Add 50 mmol of dried polytetramethylene glycol 2000, 130 mmol of diphenylmethane-4,4'-diisocyanate, and 0.07 g of dibutyltin dilaurate into a reaction container, introduce nitrogen, heat to 90° C., react for 2 h, then mix with 64 mmol of a chain extender, pour into a mold at 100° C., react at 90° C. for 2 h, then react at 120° C. for 4 h, cool and discharge to obtain a hyperbranched polyurethane elastomer.

[0024] (4) 5 kg of polypropylene, 0.5 kg of hyperbranched polyurethane elastomer, 0.1 kg of calcium carbonate, and 18 g of antioxidant 1076 are mixed in a mixer, and then passed through a twin-screw extruder with the temperatures of sections 1-6 being 150° C., 160° C., 175° C., 185° C., 185° C., and 180° C. and the screw speed being 200 r / min, and extruded and pelletized to obtain a high-strength impact-resistant modified polypropylene plastic.

[0025] Embodiment 2:

[0026] (1) Add 300 mL of ethanol, 60 mmol of terephthalaldehyde, and 120 mmol of 2-amino-1,3-propanediol to a reaction container, heat to 70° C., react for 24 h, condense and reflux during the reaction, cool to room temperature, add 156 mmol of sodium borohydride, react for 4 h, remove ethanol by rotary evaporation, and separate and purify by silica gel column to obtain terephthalimino-1,3-propanediol.

[0027] (2) Add 300 mL of ethanol, 50 mmol of 1,3-diamino-1-terephthalylidene glycol, and 110 mmol of 1-bromoeicosane into a reaction container, heat to 80° C., and react for 12 h. During the reaction, condense and reflux, and remove ethanol by rotary evaporation. After washing with water, separate and purify with a silica gel column to obtain a chain extender.

[0028] (3) Add 50 mmol of dried polytetrahydrofuran ether diol 2000, 150 mmol of toluene-2,4-isocyanate, and 0.08 g of dibutyltin dilaurate into a reaction container, introduce nitrogen, heat to 85° C., react for 3 h, then mix with 80 mmol of a chain extender, pour into a mold at 100° C., first react at 100° C. for 1.5 h, then react at 120° C. for 4 h, cool and discharge to obtain a hyperbranched polyurethane elastomer.

[0029] (4) 5 kg of polypropylene, 0.8 kg of hyperbranched polyurethane elastomer, 0.22 kg of talcum powder, and 25 g of antioxidant 168 are mixed in a mixer, and then passed through a twin-screw extruder with the temperatures of sections 1-6 being 150° C., 160° C., 175° C., 185° C., 185° C., and 180° C. and the screw speed being 200 r / min, and extruded and pelletized to obtain a high-strength impact-resistant modified polypropylene plastic.

[0030] Embodiment 3:

[0031] (1) According to the method of Example 1, terephthalimino-1,3-propanediol was prepared.

[0032] (2) Add 250 mL of ethanol, 50 mmol of 1,3-diol, and 120 mmol of 1-bromododecane to a reaction container, heat to 80° C., and react for 12 h. During the reaction, condense and reflux, and remove ethanol by rotary evaporation. After washing with water, separate and purify on a silica gel column to obtain a chain extender.

[0033] (3) Add 50 mmol of dried polytetramethylene glycol 2000, 140 mmol of diphenylmethane-4,4'-diisocyanate, and 0.07 g of dibutyltin dilaurate into a reaction container, introduce nitrogen, heat to 90° C., react for 2 h, then mix with 66 mmol of a chain extender, pour into a mold at 100° C., react at 90° C. for 2 h, then react at 120° C. for 4 h, cool and discharge to obtain a hyperbranched polyurethane elastomer.

[0034] (4) 5 kg of polypropylene, 1.2 kg of hyperbranched polyurethane elastomer, 0.4 kg of glass microspheres, and 15 g of antioxidant 1010 were mixed in a mixer, and then passed through a twin-screw extruder with the temperatures of sections 1-6 being 150° C., 160° C., 175° C., 185° C., 185° C., and 180° C. and the screw speed being 200 r / min, and extruded and pelletized to obtain a high-strength impact-resistant modified polypropylene plastic.

[0035] Embodiment 4:

[0036] (1) According to the method of Example 1, terephthalimino-1,3-propanediol was prepared.

[0037] (2) Add 350 mL of ethanol, 50 mmol of 1,3-diphenylene glycol, and 120 mmol of 1-bromotetradecane to a reaction container, heat to 75° C., and react for 18 h. During the reaction, condense and reflux, and remove ethanol by rotary evaporation. After washing with water, separate and purify on a silica gel column to obtain a chain extender.

[0038] (3) Add 50 mmol of dried polytetrahydrofuran ether diol 2000, 150 mmol of toluene-2,4-isocyanate, and 0.07 g of dibutyltin dilaurate into a reaction container, introduce nitrogen, heat to 80° C., react for 3 h, then mix with 80 mmol of a chain extender, pour into a mold at 100° C., first react at 100° C. for 1.5 h, then react at 110° C. for 5 h, cool and discharge to obtain a hyperbranched polyurethane elastomer.

[0039] (4) 5 kg of polypropylene, 1.5 kg of hyperbranched polyurethane elastomer, 0.1 kg of calcium carbonate, and 18 g of antioxidant 1076 were mixed in a mixer, and then passed through a twin-screw extruder with the temperatures of sections 1-6 being 150° C., 160° C., 175° C., 185° C., 185° C., and 180° C. and the screw speed being 100 r / min, and extruded and pelletized to obtain a high-strength impact-resistant modified polypropylene plastic.

[0040] Comparative Example 1:

[0041] (1) 5 kg of polypropylene, 0.1 kg of calcium carbonate and 18 g of antioxidant 1076 were mixed in a mixer, and then passed through a twin-screw extruder with the temperatures of sections 1-6 being 150° C., 160° C., 175° C., 185° C., 185° C. and 180° C., and the screw speed being 200 r / min, and extruded and pelletized to obtain a high-strength impact-resistant modified polypropylene plastic.

[0042] Comparative Example 2:

[0043] (1) Add 50 mmol of dried polytetramethylene glycol 2000, 130 mmol of diphenylmethane-4,4'-diisocyanate, and 0.07 g of dibutyltin dilaurate into a reaction container, introduce nitrogen, heat to 90° C., react for 2 h, then mix with 64 mmol of stearyl diethanolamine, pour into a mold at a temperature of 100° C., first react at 90° C. for 2 h, then react at 120° C. for 4 h, cool and discharge to obtain a polyurethane elastomer.

[0044] (2) 5 kg of polypropylene, 0.5 kg of polyurethane elastomer, 0.1 kg of calcium carbonate, and 18 g of antioxidant 1076 are mixed in a mixer, and then passed through a twin-screw extruder with the temperatures of sections 1-6 being 150° C., 160° C., 175° C., 185° C., 185° C., and 180° C. and the screw speed being 200 r / min, and extruded and pelletized to obtain a high-strength impact-resistant modified polypropylene plastic.

[0045] Comparative Example 3:

[0046] (1) According to the method of Example 1, terephthalimino-1,3-propanediol was prepared.

[0047] (2) Add 250 mL of ethanol, 50 mmol of 1,3-diamino-1-terephthalylidene glycol, and 116 mmol of 1-bromopropane into a reaction container, heat to 70° C., and react for 18 hours. During the reaction, condense and reflux, and remove ethanol by rotary evaporation. After washing with water, separate and purify on a silica gel column to obtain a chain extender.

[0048] (3) Add 50 mmol of dried polytetramethylene glycol 2000, 130 mmol of diphenylmethane-4,4'-diisocyanate, and 0.07 g of dibutyltin dilaurate into a reaction container, introduce nitrogen, heat to 90° C., react for 2 h, then mix with 64 mmol of a chain extender, pour into a mold at 100° C., react at 90° C. for 2 h, then react at 120° C. for 4 h, cool and discharge to obtain a hyperbranched polyurethane elastomer.

[0049] (4) 5 kg of polypropylene, 0.5 kg of hyperbranched polyurethane elastomer, 0.1 kg of calcium carbonate, and 18 g of antioxidant 1076 are mixed in a mixer, and then passed through a twin-screw extruder with the temperatures of sections 1-6 being 150° C., 160° C., 175° C., 185° C., 185° C., and 180° C. and the screw speed being 200 r / min, and extruded and pelletized to obtain a high-strength impact-resistant modified polypropylene plastic.

[0050] The modified polypropylene plastic was injected into a sample strip using an injection molding machine. The tensile properties were tested according to GB / T 1040.1-2018. The bending properties were tested according to GB / T 9341-2008. The impact properties were tested according to GB / T 1043.1-2008.

[0051] Table 1 Modified polypropylene plastic performance test

[0052]

[0053] After testing, the tensile properties, bending strength and impact strength of the polypropylene plastic in Comparative Example 1 are relatively low. In Examples 1-4, a hyperbranched polyurethane elastomer with excellent mechanical properties is added to toughen and modify the polypropylene. The hyperbranched polyurethane elastomer contains a long alkyl chain with good compatibility with polypropylene. At the same time, during the high-temperature melt extrusion process, the long alkyl chain forms a physical chain entanglement with the polypropylene molecular chain, which significantly improves the compatibility between the polyurethane elastomer and the polypropylene, and increases the interfacial force between the two, so that the hyperbranched polyurethane elastomer has a better toughening effect, and the tensile properties, bending strength and impact strength are significantly improved.

[0054] Comparative Example 2 uses stearyl diethanolamine as a chain extender, which contains a long alkyl chain. The obtained polyurethane elastomer has high compatibility and interfacial force with polypropylene, and has a good toughening effect. The tensile properties, flexural strength and impact strength of polypropylene are higher than those of Comparative Example 1. However, stearyl diethanolamine contains only two hydroxyl polymerization chain extension sites, and the obtained polyurethane elastomer does not have a hyperbranched structure, resulting in poor mechanical properties, limited toughening effect on polypropylene, and tensile properties, impact strength and other properties are lower than those of the embodiments.

[0055] In Comparative Example 3, 1,3-propanediol and 1-bromopropane are used as reactants, and the obtained chain extender does not contain long alkyl chains, resulting in poor compatibility and interfacial force between the hyperbranched polyurethane elastomer and polypropylene, and general toughening effect. The tensile properties, impact strength and other properties of polypropylene are lower than those of the embodiments.

Claims

1. A high-strength impact-resistant modified polypropylene plastic, characterized in that: The invention comprises 100 parts by weight of polypropylene, 10-30 parts by weight of hyperbranched polyurethane elastomer, 2-8 parts by weight of filler and 0.3-0.5 parts by weight of antioxidant; The preparation method of the hyperbranched polyurethane elastomer is as follows: adding dry polytetramethylene glycol, diisocyanate monomer and dibutyltin dilaurate into a reaction container, introducing nitrogen, heating to 80-90° C., reacting for 2-3 hours, and then reacting with a general structural formula The mixture is mixed with a chain extender, poured into a mold, reacted at 90-100°C for 1.5-2h, then reacted at 110-120°C for 4-5h, cooled and discharged to obtain a hyperbranched polyurethane elastomer; In the general structural formula, n is any integer between 12 and 20.

2. The high-strength impact-resistant modified polypropylene plastic according to claim 1, characterized in that: The filler includes any one of talc, calcium carbonate and glass microspheres.

3. The high-strength impact-resistant modified polypropylene plastic according to claim 1, characterized in that: The antioxidant includes any one of antioxidant 1010 , antioxidant 1076 , and antioxidant 168 .

4. The high-strength impact-resistant modified polypropylene plastic according to claim 1, characterized in that: The molar ratio of the polytetramethylene ether diol, the diisocyanate monomer and the chain extender is 1:(2.6-3):(1.2-1.6).

5. The high-strength impact-resistant modified polypropylene plastic according to claim 4, characterized in that: The diisocyanate monomer includes any one of toluene-2,4-isocyanate and diphenylmethane-4,4'-diisocyanate.

6. The high-strength impact-resistant modified polypropylene plastic according to claim 4, characterized in that: The preparation method of the chain extender is: (1) adding ethanol, terephthalaldehyde and 2-amino-1,3-propanediol in a molar ratio of 1:(2-2.2) to a reaction vessel, heating to 70-80° C., reacting for 18-24 hours, condensing and refluxing during the reaction, cooling to room temperature, adding sodium borohydride, reacting for 4-6 hours, rotary evaporation, and separation and purification by silica gel column to obtain terephthalimino-1,3-propanediol; (2) Add ethanol, p-terephthalimino-1,3-propanediol and 1-bromoalkane in a molar ratio of 1:(2.2-2.4) to a reaction container, heat to 70-80° C., react for 12-18 hours, condense and reflux during the reaction, rotary evaporate, wash, and separate and purify on a silica gel column to obtain a chain extender.

7. The high-strength impact-resistant modified polypropylene plastic according to claim 6, characterized in that: The structural formula of the 1-bromoalkane is Br-C n H 2n+1 , n is any integer between 12 and 20.

8. A method for preparing the high-strength impact-resistant modified polypropylene plastic according to any one of claims 1 to 7, characterized in that: The preparation method comprises the following steps: mixing polypropylene, hyperbranched polyurethane elastomer, filler and antioxidant in a mixer, and then extruding and pelletizing through a twin-screw extruder with the temperature of sections 1-6 being 150-185°C and the screw speed being 100-200 r / min to obtain high-strength impact-resistant modified polypropylene plastic.

9. Use of the high-strength impact-resistant modified polypropylene plastic obtained by the preparation method as claimed in claim 8 in durable toys.

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