CN112778675A - Oil-resistant high-gloss polystyrene material and preparation method and application thereof - Google Patents
Oil-resistant high-gloss polystyrene material and preparation method and application thereof Download PDFInfo
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- CN112778675A CN112778675A CN202011539775.8A CN202011539775A CN112778675A CN 112778675 A CN112778675 A CN 112778675A CN 202011539775 A CN202011539775 A CN 202011539775A CN 112778675 A CN112778675 A CN 112778675A
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- polystyrene
- polystyrene material
- oil
- thermoplastic elastomer
- density polyethylene
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L51/00—Compositions of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
- C08L51/04—Compositions of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers grafted on to rubbers
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2203/00—Applications
- C08L2203/20—Applications use in electrical or conductive gadgets
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2207/00—Properties characterising the ingredient of the composition
- C08L2207/04—Thermoplastic elastomer
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2207/00—Properties characterising the ingredient of the composition
- C08L2207/06—Properties of polyethylene
- C08L2207/062—HDPE
Abstract
The invention discloses an oil-resistant high-gloss polystyrene material, a preparation method and application thereof, wherein the oil-resistant high-gloss polystyrene material comprises high-impact polystyrene, high-density polyethylene, an interface improver and an antioxidant in a certain proportion, the interface improver is a vinyl and diene thermoplastic elastomer with a certain molecular weight, the high-impact polystyrene is used as a matrix material, has high gloss, and also contains the high-density polyethylene and the interface improver.
Description
Technical Field
The invention relates to the technical field of oil-resistant high-gloss modified polymer materials, in particular to an oil-resistant high-gloss polystyrene material and a preparation method and application thereof.
Background
High Impact Polystyrene (HIPS) is a two-phase system consisting of a rubber phase and a continuous polystyrene phase, and the special 'sea island structure' of the HIPS endows the material with excellent toughness and rigidity and good processability and dimensional stability, and is widely applied to the fields of household appliances, electronic appliances, offices, toys, packaging and the like. The HIPS is required to have high glossiness on the surface in many applications so as to improve the attractiveness and the grade of a product, the HIPS with high glossiness has poor oil resistance, and can contact oil substances in certain use environments, particularly when the HIPS is applied to kitchen appliances such as refrigerators, and the like.
Chinese patent CN 104744868A discloses an impact-resistant styrene polymer composition for refrigerator plates, which is characterized in that a styrene-butadiene-styrene block copolymer is added into HIPS to improve the oil resistance and toughness of HIPS, and although the oil resistance can be improved to a certain extent, the surface gloss is reduced, and if the addition amount of a thermoplastic elastomer is reduced, the oil resistance is reduced, so that the oil resistance and high gloss of the styrene polymer composition cannot be improved at the same time.
Disclosure of Invention
The invention aims to solve the technical problem that the existing modified high impact polystyrene cannot have good oil resistance and high gloss at the same time, and provides an oil-resistant high-gloss polystyrene material which has good oil resistance, high gloss and toughness at the same time.
The invention also aims to provide a preparation method of the oil-resistant high-gloss polystyrene material.
The invention also aims to provide application of the oil-resistant high-gloss polystyrene material.
The above purpose of the invention is realized by the following technical scheme:
the oil-resistant high-gloss polystyrene material comprises the following components in parts by mass:
60-90 parts of high impact polystyrene;
1-20 parts of high-density polyethylene;
1-15 parts of an interface improver;
the average particle size of the high impact polystyrene is less than or equal to 1 um;
the weight average molecular weight of the high-density polyethylene is 20-50 ten thousand;
the interfacial modifier is a thermoplastic elastomer containing vinyl and diene groups and having a weight average molecular weight of 200000 to 300000.
The oil-resistant high-gloss polystyrene material disclosed by the invention selects HIPS (high impact polystyrene) with a smaller particle size as a base material, so that the polystyrene material is ensured to have high gloss and good toughness; the high-density polyethylene with high molecular weight is adopted, the high-density polyethylene has very high crystallinity and tight molecular weight arrangement, can well block the permeation of oil substances, has high molecular weight and better oil resistance, has higher self fluidity, and is easy to migrate to the surface to form an oil-resistant protective layer to block the permeation of oil. In addition, a proper amount of interface improver is added, so that the compatibility of HIPS and high-density polyethylene can be improved, the layering phenomenon is prevented, oil substances are easily adsorbed due to the mesh structure, the erosion of the oil substances is relieved, the oil resistance is good, the overall toughness of the material can be improved by controlling the molecular weight and the using amount of the interface improver, the function of a toughening agent is realized, and the high glossiness and the oil resistance are maintained.
Preferably, the composition comprises the following components in parts by mass:
70-90 parts of high impact polystyrene;
2-12 parts of high-density polyethylene;
1-10 parts of an interface improver.
Preferably, the weight average molecular weight of the thermoplastic elastomer containing vinyl and diene groups is 200000 to 250000.
Preferably, the high impact polystyrene has an average particle diameter of 0.8 μm or less.
Preferably, the high density polyethylene has a weight average molecular weight of 30 to 50 ten thousand.
Preferably, the thermoplastic elastomer containing vinyl and diene groups is one or more of a styrene-butadiene thermoplastic elastomer, a hydrogenated styrene-butadiene thermoplastic elastomer, a styrene-butadiene-styrene thermoplastic elastomer, and an ethylene-styrene-butadiene thermoplastic elastomer.
Preferably, one or more of a flame retardant, an antioxidant, a lubricant, a filler and a colorant are also included.
The antioxidant of the present invention includes, but is not limited to, hindered phenol antioxidants and/or alcohol ester antioxidants.
The antioxidant comprises but is not limited to one or more of a tetra [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid ] pentaerythritol ester and tri [2, 4-di-tert-butylphenyl ] phosphite compound, a tri [2, 4-di-tert-butylphenyl ] phosphite and n-octadecyl beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate compound, a tri [2, 4-di-tert-butylphenyl ] phosphite and a dilauryl thiodipropionate compound, and the compound ratio is 1 (1-3).
The lubricant of the present invention includes, but is not limited to, one or more of stearate lubricants, amide lubricants, and stearate lubricants.
The stearate lubricant provided by the invention comprises one or more of calcium stearate, magnesium stearate and zinc stearate.
The stearate-based lubricants of the present invention include, but are not limited to, glyceryl monostearate and/or pentaerythritol stearate.
The filler of the invention includes but is not limited to one or more of fibrous filler and non-fibrous filler.
The fibrous filler provided by the invention comprises one or more of but not limited to glass fiber, carbon fiber, organic fiber, basalt fiber, bamboo fiber, hemp fiber, cellulose fiber and aramid fiber.
The non-fibrous filler of the present invention includes, but is not limited to, one or more of alumina, carbon black, clay, zirconium phosphate, kaolin, calcium carbonate, copper, diatomaceous earth, graphite, mica, silica, titanium dioxide, zeolite, talc, wollastonite, glass beads, and glass powder.
The invention protects the preparation method of the polystyrene material, which comprises the following steps:
the high impact polystyrene, the high density polyethylene and the interface improver are uniformly mixed, then are melted and blended, and are extruded and granulated to prepare the polystyrene material.
The invention also protects the application of the polystyrene material in preparing the polystyrene material with high gloss and oil resistance for products.
Preferably, the melting and the mixing are carried out in a parallel double-screw extruder, in the aspect of screw combination design, only one reverse thread is arranged in a melting section, a 45-degree kneading block is selected to replace a 90-degree kneading block to weaken shearing, so that the network structure of the interface modifier is protected, the mixing and compatibilization effect of the material is improved, in order to improve the compatibility of two phases, a weak shearing screw is adopted in the preparation method, the surface enrichment of the high-density polyethylene is improved, the network structure of the interface modifier is protected, and the compatibility of the high-impact polystyrene and the high-density polyethylene is improved. And simultaneously, a toothed disc is added, so that the melt mixing effect is improved.
Preferably, the feeding speed of the parallel double-screw extruder is 200-300 rpm, and the screw rotating speed is 300-500 rpm.
Preferably, the temperature of each section of screw of the parallel double-screw extruder is set to be 80-100 ℃ in a first zone, 160-180 ℃ in a second zone, 190-210 ℃ in a third zone, 190-210 ℃ in a fourth zone, 190-210 ℃ in a fifth zone, 180-200 ℃ in a sixth zone, 180-200 ℃ in a seventh zone, 190-210 ℃ in an eighth zone, 190-210 ℃ in a ninth zone and 200-220 ℃ in a head from a feed inlet to the head in sequence.
An oil-resistant product with high gloss is prepared from the polystyrene material.
Compared with the prior art, the invention has the beneficial effects that:
the oil-resistant high-gloss polystyrene material disclosed by the invention takes high-impact polystyrene with small particle size as a base material, has high gloss, also contains high-density polyethylene, can form a better oil-resistant protective layer to prevent oil from permeating, is added with a certain content of interface improver to improve the compatibility of HIPS and high-density polyethylene and the oil resistance of the material, and cannot influence the gloss of the material.
Detailed Description
The present invention will be further described with reference to specific embodiments, but the present invention is not limited to the examples in any way. The starting reagents employed in the examples of the present invention are, unless otherwise specified, those that are conventionally purchased.
The main components used in the examples and comparative examples:
HIPS-1: high impact polystyrene, rubber average particle size of 0.8um, brand PH-888G, purchased in taiwan curiosity;
HIPS-2: high impact polystyrene, the average particle size of rubber is 1.2um, the mark is HIPS 8250, and the high impact polystyrene is purchased from Taiwan;
HDPE-1: high density polyethylene, weight average molecular weight 30 ten thousand; trade designation ELTEX TUB124, available from solvay;
HDPE-2: high density polyethylene, weight average molecular weight 20 ten thousand; trade designation ELTEX TUB131, available from solvay;
HDPE-3: high density polyethylene, weight average molecular weight 50 ten thousand;
HDPE-4: high density polyethylene, weight average molecular weight 10 ten thousand;
HDPE-5: high density polyethylene, weight average molecular weight 70 ten thousand;
interface improver-1: styrene-butadiene thermoplastic elastomer, having a weight average molecular weight of 20 ten thousand and a brand number of LG-501, purchased in LG chemistry of korea;
interface improver-2: a styrene-butadiene thermoplastic elastomer having a weight average molecular weight of 30 ten thousand;
interface improver-3: a styrene-butadiene thermoplastic elastomer having a weight average molecular weight of 15 ten thousand;
interface improver-4: a styrene-butadiene thermoplastic elastomer having a weight average molecular weight of 35 ten thousand;
interface improver-5: hydrogenated styrene-butadiene thermoplastic elastomer, weight average molecular weight 30 ten thousand, model number SEBS 6151, purchased from Taiwan rubber of China;
interface improver-6: styrene-butadiene copolymer, brand KR-03, purchased from korean phillips;
antioxidant: pentaerythritol ester antioxidants and phosphite ester antioxidants;
lubricant: ethylene bis stearamide.
Example 1
An oil-resistant high-gloss polystyrene material comprises the components in parts by mass as shown in the following table 1.
A preparation method of an oil-resistant high-gloss polystyrene material comprises the following steps:
uniformly mixing the high impact polystyrene, the high density polyethylene, the styrene-butadiene thermoplastic elastomer, the antioxidant and the lubricant, then melting by adopting a parallel double-screw extruder with weak shearing, melting, mixing, extruding and granulating; wherein the feeding speed of the extruder is 35rpm, the rotating speed of the screw is 450rpm, the temperature of each section of the screw of the extruder is set to be 100 ℃ in a first region, 180 ℃ in a second region, 200 ℃ in a third region, 200 ℃ in a fourth region, 200 ℃ in a fifth region, 190 ℃ in a sixth region, 190 ℃ in a seventh region, 190 ℃ in an eighth region, 200 ℃ in a ninth region and 210 ℃ in a head from a feeding port to the head, and the oil-resistant high-gloss polystyrene material is obtained.
Examples 2 to 11 and comparative examples 1 to 8
The polystyrene materials of examples 2 to 11 and comparative examples 1 to 8, which include the components in parts by mass shown in the following table 1, were prepared in the same manner as in example 1.
TABLE 1 Components and parts by mass of examples and comparative examples
Performance testing
1. Test method
(1) Gloss: the surface gloss was measured by injection molding into 2mm square plates according to ISO 2813-2014 standard.
(2) Surface cracking after oiling: standard tensile bars were prepared according to ISO 527-1-2012 standard. Fixing the tensile sample strip on a clamp applying 1% strain, uniformly coating three drops of sunflower seed oil on the surface of the sample strip, standing at room temperature for 24h, and observing the cracking condition of the surface of the sample strip.
(3) Elongation at break and elongation retention after oiling: the test speed is 50mm/min according to ISO 527-1-2012 standard. And respectively testing the elongation at break after 24 hours of oiling and 24 hours of oiling, and calculating the retention rate of the elongation at break.
(4) Flexural modulus: the test speed is 2mm/min according to the ISO 178-2010 standard.
2. Test results
TABLE 2 results of performance test of modified polystyrene materials obtained in examples and comparative examples
From the results in table 2, it can be seen that the pure HIPS resin of comparative example 1 has poor oil resistance, and the elongation at break after oiling is only 4.5%, while the polystyrene material of each example has high elongation at break and high elongation retention after oiling for 24 hours, which indicates that the polystyrene material has good oil resistance, and simultaneously maintains high gloss characteristics, and in addition, the polystyrene material has high flexural modulus and good rigidity, and can meet the application requirements of practical products.
As can be seen from comparative examples 2 to 3, the material surface gloss was poor and the oil resistance was also poor without adding high density polyethylene. However, the addition of too much high density polyethylene lowers the elongation at break after oiling although the elongation at break retention is high, and the oil resistance is deteriorated. Meanwhile, the flexural modulus is low, and the use requirement of the material cannot be well met; as can be seen from comparative examples 4 to 5, the oil resistance of the material was also poor without adding a styrene-butadiene copolymer as an interface improver. And the use level of the interface improver is too high, so that the glossiness of the material is obviously reduced. As can be seen from comparative examples 6 to 7, the high density polyethylene having a low molecular weight does not exhibit a good oil resistance. The molecular weight is higher, the influence on the surface gloss of the material is larger, and the molecular weight is higher, so that the material is difficult to well migrate to the surface to form a protective layer, and the oil resistance is not high; from comparative examples 8 to 9, it can be seen that when the molecular weight of the interface improver is low, the oil resistance of the polystyrene material is poor, and when the molecular weight of the interface improver is high, the glossiness of the polystyrene material is low; as can be seen from comparative example 10, when the interface improver was changed to a styrene-butadiene copolymer, the oil resistance of the material was poor. As can be seen from comparative example 11, the rubber average particle size of the high impact polystyrene is too large to improve the surface gloss of the polystyrene material.
It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.
Claims (10)
1. The oil-resistant high-gloss polystyrene material is characterized by comprising the following components in parts by mass:
60-90 parts of high impact polystyrene;
1-20 parts of high-density polyethylene;
1-15 parts of an interface improver;
the average particle size of the high impact polystyrene is less than or equal to 1 um;
the weight average molecular weight of the high-density polyethylene is 20-50 ten thousand;
the interfacial modifier is a thermoplastic elastomer containing vinyl and diene groups and having a weight average molecular weight of 200000 to 300000.
2. The polystyrene material according to claim 1, comprising the following components in parts by mass:
70-90 parts of high impact polystyrene;
2-12 parts of high-density polyethylene;
1-10 parts of an interface improver.
3. The polystyrene material according to claim 1 or 2, wherein the weight average molecular weight of the thermoplastic elastomer containing vinyl groups and diene groups is 200000 to 250000.
4. The polystyrene material of claim 1, wherein the high impact polystyrene has an average particle size of 0.8um or less.
5. The polystyrene material of claim 1, wherein the high-density polyethylene has a weight-average molecular weight of 30 to 50 ten thousand.
6. The polystyrene material of claim 1, wherein the thermoplastic elastomer containing vinyl groups and diene groups is one or more of a styrene-butadiene thermoplastic elastomer, a hydrogenated styrene-butadiene thermoplastic elastomer, a styrene-butadiene-styrene thermoplastic elastomer, and an ethylene-styrene-butadiene thermoplastic elastomer.
7. The polystyrene material of claim 1, further comprising one or more of a flame retardant, an antioxidant, a lubricant, a filler, and a colorant.
8. A method for preparing a polystyrene material as claimed in any one of claims 1 to 7, comprising the steps of:
the high impact polystyrene, the high density polyethylene and the interface improver are uniformly mixed, then are melted and blended, and are extruded and granulated to prepare the polystyrene material.
9. Use of the polystyrene material according to any one of claims 1 to 7 for the preparation of a high gloss polystyrene material for oil resistant articles.
10. An oil-resistant product having high gloss, which is characterized by comprising the polystyrene material according to any one of claims 1 to 7.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6008294A (en) * | 1991-12-20 | 1999-12-28 | The Dow Chemical Company | Thermoformable, chemical resistant polymer blends |
| US20040167279A1 (en) * | 2001-07-27 | 2004-08-26 | Daniel Wagner | Shiny, impact-resistant polystyrol which is resistant to tension cracks |
| CN104098865A (en) * | 2014-07-03 | 2014-10-15 | 合肥杰事杰新材料股份有限公司 | Polystyrene-polyethylene resin alloy material used for refrigerator inner container and preparation method thereof |
-
2020
- 2020-12-23 CN CN202011539775.8A patent/CN112778675B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6008294A (en) * | 1991-12-20 | 1999-12-28 | The Dow Chemical Company | Thermoformable, chemical resistant polymer blends |
| US20040167279A1 (en) * | 2001-07-27 | 2004-08-26 | Daniel Wagner | Shiny, impact-resistant polystyrol which is resistant to tension cracks |
| CN104098865A (en) * | 2014-07-03 | 2014-10-15 | 合肥杰事杰新材料股份有限公司 | Polystyrene-polyethylene resin alloy material used for refrigerator inner container and preparation method thereof |
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