AU2020101213A4

AU2020101213A4 - Polystyrene composite material and preparation method thereof

Info

Publication number: AU2020101213A4
Application number: AU2020101213A
Authority: AU
Inventors: Jianjian DAI; Jinfeng FU; Huanxiang GUAN; Baokui Huang; Xianbo Huang; Lei Tang; Xiaoyun Yang; Nanbiao Ye
Original assignee: Kingfa Science and Technology Co Ltd
Current assignee: Kingfa Science and Technology Co Ltd
Priority date: 2018-12-27
Filing date: 2020-07-01
Publication date: 2020-08-06
Anticipated expiration: 2028-07-01
Also published as: CN109971107A; WO2020134844A1

Abstract

The invention discloses a polystyrene composite material, which is characterized in that it comprises the following components by weight: 100 parts of polystyrene-polybutadiene graft copolymer, 5-70 parts of polyacrylate polymer and 1-15 parts of styrene-acrylate copolymer. The polystyrene composite material has the advantages of good willfulness and good appearance.

Description

Editorial Note 2020101213 There is only five pages of the description

Polystyrene composite material and preparation method thereof

Technical Field The invention relates to the technical field of polymer materials, in particular to a polystyrene composite material and a preparation method thereof.

Background Technique Polystyrene is a kind of polymer synthesized by free radical polymerization of styrene monomer. Polystyrene includes ordinary polystyrene, expanded polystyrene, high impact polystyrene and syndiotactic polystyrene. HIPS is a graft copolymer of styrene and polybutadiene rubber. As a rubber toughener, polybutadiene improves the impact strength and makes HIPS have high strength and good toughness at the same time. It is widely used in household appliances, electronic appliances and packaging industry. However, high impact polystyrene contains rubber with large particle size structure, which makes the material surface soft. When it is used for shell materials, the products will inevitably collide and rub with hard objects in the process of preparation, transportation and use, which makes the surface easy to appear obvious scratches, affects the surface beauty and hinders its application. The general method is to add scratch resistance agent to increase the scratch resistance, but only add scratch resistance agent, can only reduce the clarity of the scratch, can not improve the material surface resistance to sharp objects. In addition, the excessive addition of scratch resistant agent also increases the risk of precipitation during use and reduces the durability. Another way is to add a large number of fillers to increase the scratch resistance, but fillers will seriously reduce the surface gloss of the material and affect the aesthetics of the parts. Moreover, it can also reduce the toughness of the material.

Summary of The Invention The invention aims to overcome the above technical defects and provide a polystyrene composite material, which has the advantages of good toughness and good appearance. Another object of the invention is to provide a preparation method of the polystyrene composite material. The invention is realized by the following technical scheme: A polystyrene composite material comprises the following components by weight: Polystyrene polybutadiene graft copolymer (HIPS) 100 phr; Polyacrylate polymer 5-70 phr; Styrene acrylate copolymer 1-15 phr. The addition of polyacrylate polymer can improve the surface hardness of HIPS and improve the scratch resistance. However, the compatibility between HIPS and polyacrylate polymers is very poor. When more polyacrylate polymers are added, they will condense to form tiny clusters, which not only leads to a sharp decline in toughness, but also leads to "dark lines", and the glossiness decreases, and the surface has pearly luster, which affects the appearance. The existing compatibilizers can not make them compatible well (styrene nylon 6 graft copolymer, styrene ethylene / propylene diblock copolymer have good compatibility with HIPS, but they are not compatible with Polyacrylate Polymers, so they can not play a good role in compatibilizing Polyacrylate Polymers; SBS or SEBS have good compatibility with HIPS, but they are compatible with Polyacrylate Polymers Poor compatibility, at the same time will have a great impact on gloss). The invention finds that styrene acrylate copolymer, as a compatibilizer, can effectively improve the compatibility of HIPS and polyacrylate, thereby improving the phenomenon of dark lines and pearlescent, improving the surface glossiness, improving the surface hardness and ensuring the toughness of the composite. The polyacrylate polymer is selected from at least one of methyl acrylate polymer, ethyl acrylate polymer, propyl acrylate polymer, butyl acrylate polymer and amyl acrylate polymer; It is preferred that the polyacrylate polymer is selected from at least one of polyacrylate methyl ester polymer and polyacrylate ethyl ester polymer. The hardness and glossiness of the polystyrene composite can be adjusted according to the Polyacrylate Polymers with different substituents. The hardness and glossiness of the two kinds of polyacrylate polymers are comprehensive high, and can meet the requirements of improving the hardness and glossiness in common cases with a small amount of addition. The weight average molecular weight of the polyacrylate polymer MW is 800OOg / mol-300000 g / mol; Taking the comprehensive properties of the hardness and processability of the polystyrene composite as the priority index, the weight average molecular weight of the polyacrylate polymer is 140000g / mol-190000g / mol. The higher the weight average molecular weight of polyacrylate polymer is, the higher the hardness is, and the better the hardness of polystyrene composite is. However, the molecular weight of polyacrylate polymer is too large, which will lead to too hard and increase the processing difficulty. The styrene acrylate copolymer is selected from at least one of styrene acrylate copolymer and styrene butadiene acrylate copolymer. In general, styrene acrylate copolymer is usually used to prepare core-shell structure for toughening. Specifically, styrene butadiene acrylate copolymers are generally used to prepare core-shell MBS and toughen PVC. Styrene acrylate copolymer can be prepared into emulsion type for coating. Up to now, there is no report on the compatibilization application of HIPS and Polyacrylate Polymers, and styrene acrylate copolymer has a certain gloss, which can further improve the glossiness of polystyrene composites and achieve the good appearance effect of high gloss. Preferably, the content of acrylate in the styrene acrylate copolymer is in the range of 20-60%. When the content of acrylate is in the range of 20-60%, the compatibility of styrene acrylate copolymer to HIPS and polyacrylate is better. Preferably, the weight average molecular weight Mw of the polystyrene polybutadiene graft copolymer is 80000 g / mol to 180000 g / mol, and the content of polybutadiene is 10% to 40% based on the total weight of the polystyrene polybutadiene graft copolymer chain segment. When the parameters of ps-pbg are in the above range, the material can obtain better comprehensive mechanical properties and processing properties, which can meet the practical application needs. The test result of weight average molecular weight of general polymer is a "inverted U-shaped curve" similar to normal distribution in a wide range, with a maximum value, which falls into the protection range of the invention as long as the maximum value is within the required range of the invention.

The scratch resistance agent can also include 0-3 parts of scratch resistance agent by weight; the scratch resistance agent is selected from at least one of stearate scratch resistance agent and silicone scratch resistance agent. It also includes 0.1-10 parts of Auxiliaries by weight; the auxiliaries are selected from at least one of flame retardant, heat stabilizer, antioxidant, flame retardant synergist, anti dropping agent, light stabilizer, plasticizer, filler and colorant. The lubricant is stearic acid metal salt lubricant, stearic acid alkyl ester lubricant, stearic acid pentaerythritol ester lubricant, paraffin or lignite wax. The heat stabilizer is an organic phosphite, preferably a triphenyl phosphite, a tris (2,6-Dimethylphenyl) phosphite, a tris nonylphenyl phosphite, a dimethylphenylphosphonate or a trimethyl phosphite. The antioxidant is an organic phosphite ester, alkylated monophenol or polyphenol, alkylation reaction product of polyphenol and diene, butyl reaction product of p-cresol or dicyclopentadiene, alkylated hydroquinone, hydroxylated thiodiphenyl ether, alkylene bisphenol, benzyl compound or polyol ester antioxidant. The flame retardant synergist is a silicon containing compound or a fluorinated compound, preferably siloxane, two methyl siloxane, phenyl siloxane, methoxy siloxane, polytetrafluoroethylene, acrylonitrile butadiene copolymer SAN coated polytetrafluoroethylene, polycarbonate PC coated polytetrafluoroethylene, emulsion polytetrafluoroethylene or Perfluorosulfonate. The light stabilizer is at least one of benzotriazole light stabilizers or benzophenone light stabilizers. The plasticizer is phthalate ester. The colorant is pigment or dye. The preparation method of the polystyrene composite material comprises the following steps: Weigh the raw materials according to the ratio, mix the polystyrene polybutadiene graft copolymer, polyacrylate, styrene acrylate copolymer and additives evenly at high speed, and then melt and extrude in the main machine to obtain polystyrene composite material. The screw temperature is 210-230 C. The invention has the following beneficial effects The invention improves the hardness of the composite material by adding polyacrylate into the polystyrene polybutadiene graft copolymer (HIPS), and then improves the compatibility of the polystyrene polybutadiene graft copolymer and the polyacrylate by adding the special compatibilizer styrene acrylate copolymer, thus ensuring the toughness of the material and further improving the hardness (scratch resistance) Can be good, can keep good appearance for a long time), eliminate dark lines, pearlescent, and improve the surface gloss. In conclusion, the polystyrene composite material of the invention has the advantages of high toughness and good appearance.

Detailed Description of preferred Embodiment The invention is further described by the following embodiments, but the invention is not limited by the following embodiments. The raw materials used in the invention all come from commercially available products. The weight average molecular weight is about 140000 g / mol, and the content of polybutadiene is about 33%; Styrene acrylate copolymer A: the content of acrylate is about 46%; The content of styrene acrylate copolymer B: acrylate is about 76%; PMMA-a: the highest weight average molecular weight is about 161000g /mol; PMMA-b: the highest weight average molecular weight is about 129000g /mol; The highest weight average molecular weight of PEBA is about 154000g / mol; Poly (butyl methacrylate) (PMBA): the highest weight average molecular weight is about 189000g / mol; Poly (butyl methacrylate) (PBMA): the highest weight average molecular weight is about 146000g / mol; Other compatibilizer A: styrene ethylene / propylenediblock copolymer; Other compatibilizer B: SEBS; Antioxidant: pentaerythritol ester antioxidant, phosphite ester antioxidant; Lubricant: ethylene distearamide. Embodiment and preparation method of proportioned polystyrene composite: weigh the raw materials according to the proportioning, mix the polystyrene polybutadiene graft copolymer, polyacrylate, styrene acrylate copolymer (or other compatibilizer) and auxiliary agent uniformly at high speed, melt and extrude them into the host machine to obtain polystyrene composite, and screw temperature is 210-230 C. Performance test methods: (1) Impact strength: according to GB 1843-1996 plastic cantilever beam impact test method, pendulum energy 2.75J, room temperature test. (2) Hardness: Rockwell hardness shall be tested according to gb230.1-2004 Rockwell hardness test method, and the test sample shall be a disc with a diameter of 6 mm; pencil hardness shall be tested according to GB / T 6739-2006 "paints and varnishes Determination of paint film hardness by pencil method". (3) Hundred grid: inject 100 X 100mm square plate with dermatoglyph, and make a hundred grid according to the grid test of paint film for paints and varnishes (GB9286-1998). Then observe thescratch A L under the microscope, and the smaller the A L,thebetter. (4) Glossiness: the glossiness shall be tested at an angle of 60 ° in accordance with GB / T 8807-1988 test method for specular gloss of plastics. (5) Dark lines: the rectangular plates with a length of 200 mm, a width of 50 mm and a thickness of 2 mm were injected, and the surface dark lines were observed by visual inspection.

Table 1: distribution ratio of each group (weight portion) and performance test results of polystyrene composite material in the embodiment El E2 E3 E4 E5 E6 E7 E8 HIPS 100 100 100 100 100 100 100 100 PMMA-A 12 - - - - 25 50 12 PMMA-B - 12 - - - - -

PEBA - - 12 - - - -

PMBA - - - 12 - - -

PBMA - - - - 12 - - Styrene acrylate 6 6 6 6 6 10 15 - copolymer A Styrene acrylate 6 copolymer B Impact strength, 8.8 8.5 9.2 8.6 7.9 7.1 6.6 8.3 kJ / m2 Rockwell 107 104 105 108 105 110 114 105 hardness After one hundred 0.48 0.75 0.53 0.42 0.58 0.38 0.21 0.67 grid A L gloss 82 78 74 73 81 85 91 80 Dark Lines No No No No No No No No

Table 2: distribution ratio (weight fraction) and performance test results of proportioned Polystyrene Composites CEl CE2 CE3 HIPS 100 100 100 PMMA-A 12 12 12 Styrene ethylene / propylene 6 diblock copolymer SEBS - - 6 Impact strength, kJ / m2 4.6 4.9 5.3 Rockwell hardness 102 97 94 After one hundred grid A L 0.92 1.16 1.32 gloss 67 58 47 Dark Lines Yes Yes Yes

It can be seen from the proportion and examples that adding styrene acrylate copolymer as compatibilizer can maximize the toughness of the composite and obtain good appearance quality. It can be seen from the ratio of 2-3 and the embodiment that styrene acrylate copolymer as compatibilizer has the best compatibilizing effect on HIPS and Polyacrylate Polymers, and can greatly improve the gloss. It can be seen from examples 1-5 that the hardness and glossiness of the product added with polymethyl polyacrylate are relatively high. It can be seen from example 1 and example 2 that when the comprehensive performance of hardness and processability of polystyrene composite is taken as the priority index, the weight average molecular weight Mw of polyacrylate polymer is 140000g / mol-190000 g / mol. From examples 1 and 8, it can be seen that the styrene acrylate copolymer has good performance in the preferred range, especially for the notch impact strength.

Claims

Editorial Note 2020101213 There is only one page of the claim

1. A polystyrene composite material, which is characterized in that it comprises the following components by weight: Polystyrene-polybutadiene graft copolymer 100 phr; Polyacrylate polymer 5-70 phr; Styrene-acrylate copolymer 1-15 phr.

2. The polystyrene composite material according to claim 1, which is characterized in that the polyacrylate polymer is selected from at least one of methyl acrylate polymer, ethyl acrylate polymer, propyl acrylate polymer, butyl acrylate polymer and amyl acrylate polymer; preferably, it is selected from at least one of methyl acrylate polymer and ethyl Polyacrylate Polymers.

3. The polystyrene composite material according to claim 1 or 2, which is characterized in that the weight average molecular weight of the polyacrylate polymer Mw is 80000 g / mol-300000 g / mol; preferably, the weight average molecular weight of the polyacrylate polymer Mw is 140000 g / mol-190000 g / mol.

4. The polystyrene composite material according to claim 1, which is characterized in that the styrene-acrylate copolymer is selected from at least one of the styrene-acrylate copolymer and the styrene-butadiene-acrylate copolymer.

5. The polystyrene composite material according to claim 1 or 4, which is characterized in that the content of acrylate in the styrene-acrylate copolymer is in the range of 20-60%.

6. The polystyrene composite material according to claim 1, which is characterized in that the weight average molecular weight of the polystyrene-polybutadiene graft copolymer Mw is 800OOg / mol to 180000g / mol, and the polybutadiene content is 10% to 40% based on the total weight of the chain segment of the polystyrene-polybutadiene graft copolymer.

7. The polystyrene composite material according to claim 1, which is characterized in that it also comprises 0-3 parts of scratch resistant agent by weight; the scratch resistant agent is selected from at least one of stearate scratch resistant agent and silicone scratch resistant agent.

8. The polystyrene composite material according to claim 1, which is characterized in that it also comprises 0.1-10 parts of auxiliaries by weight; the auxiliaries are selected from at least one of flame retardant, heat stabilizer, antioxidant, flame retardant synergist, anti dropping agent, light stabilizer, plasticizer, filler and coloring agent.

9. The preparation method of the polystyrene composite material according to claim 8, which is characterized in that it comprises the following steps: The raw materials were weighed according to the ratio, and then the polystyrene-polybutadiene graft copolymer, polyacrylate, styrene-acrylate copolymer and additives were mixed uniformly at high speed, and then the polystyrene composite was obtained by melting extrusion granulation in the main machine, and the screw temperature was 210-230 C.