TW202413520A - A plastic composite material and a preparation method thereof - Google Patents

Abstract

The present invention provides a plastic composite material and a preparation method thereof. The composite material is made of the following components in weight percentage: 30%-85% polystyrene, 15%-55% synthetic rubber, 3%-45% emulsified synthetic rubber, and 0.1%-10% auxiliary agent. The preparation method comprises crushing recycled materials and/or scraps containing polystyrene, synthetic rubber, and emulsified synthetic rubber; The weight percentage of each component is 30%-85% of the polystyrene, 15%-55% of the synthetic rubber, and 3%-45% of the emulsified synthetic rubber; the weighed polystyrene, the synthetic rubber, and the emulsified synthetic rubber are mixed to obtain a mixed material; the mixed material is fed into the main feed port, and 0.1-10% of the auxiliary agent is fed into the side feed port for granulation to obtain a plurality of granular plastic composite materials. The plastic composite material of the present invention is suitable for application in injection molding process, and compared with extrusion molding, subsequent processing is omitted, production cost is reduced, and production efficiency is improved.

Description

A plastic composite material and a preparation method thereof

The present invention relates to the technical field of composite materials, and in particular to a plastic composite material and a preparation method thereof.

Wood Plastic Composite (WPC) is made by crushing plastic raw materials, grinding wood raw materials such as sawdust or rice husks/wood fiber, mixing them in a certain proportion, extruding them into boards, and then processing them into other products. Since wood plastic composites have the advantages of wood and plastic, they can replace the original solid wood materials or plastic products and can be widely used in the building materials industry, gift industry, automobile industry, interior decoration, furniture industry, etc. Moreover, the raw materials used are derived from recyclable plastics and wood, which can be recycled and reused, and are friendly to the ecological environment.

However, plastic and wood fiber (wood powder) have different polarities and need a coupling agent or adhesive to combine the two. Wood powder used as filler in wood-plastic composites is to make the plastic wood more like real wood, but adding too much will increase the water absorption rate of the plastic wood, reduce the density of the plastic wood, and make the plastic wood easy to rot, break, crack or deform.

In addition, during the extrusion process, the plastic raw materials containing wood powder have high viscosity when melted at high temperature, which is not conducive to extrusion production, and the products after demolding are not easy to form. If calcium carbonate is added during the production process, although it can reduce the viscosity, it will make the plastic wood hard and brittle, and long-term use will easily cause the plastic wood to crack or burst.

Therefore, it is necessary to provide a composite material that does not need to add wood powder components and is suitable for forming and manufacturing, especially a plastic composite material for injection molding.

In view of the above, the present invention aims to provide a plastic composite material, which is made of the following components in weight percentage: polystyrene 30%-85%, synthetic rubber 15%-55%, emulsified synthetic rubber 3%-45%, and auxiliary agent 0.1-10%.

Furthermore, the auxiliary agent includes at least one or a combination of an organic stabilizer, a coupling agent, a thermal stabilizer, a gelling accelerator, a foaming agent, and a light absorber.

Furthermore, the weight percentage of the organic stabilizer is 0.1%-10%, the weight percentage of the coupling agent is 0.1%-5%, the weight percentage of the thermal stabilizer is 0.1%-3%, the weight percentage of the gelling accelerator is 0.1%-10%, the weight percentage of the foaming agent is 0.1%-3%, and the weight percentage of the light absorber is 0.1%-3%.

Furthermore, the polystyrene is derived from recycled materials or scraps of plastic waste.

Furthermore, the synthetic rubber and/or the emulsified synthetic rubber is derived from recycled materials or scraps of rubber waste.

Furthermore, the recycled material and/or the scrap material has at least one of the shapes of strips, blocks, and shavings.

Furthermore, the light absorber absorbs ultraviolet light of 300nm-325nm.

Furthermore, the light absorber absorbs ultraviolet light of 313nm-318nm.

The present invention also provides a method for preparing a plastic composite material, comprising the steps of crushing recycled materials and/or scraps containing polystyrene, synthetic rubber, and emulsified synthetic rubber; weighing 30%-85% of the polystyrene, 15%-55% of the synthetic rubber, and 3%-45% of the emulsified synthetic rubber according to the weight percentage of each component of the composite material; mixing the weighed polystyrene, synthetic rubber, and emulsified synthetic rubber to obtain a mixed material; feeding the mixed material into a main feed port, and feeding 0.1%-10% of an auxiliary agent into a side feed port to perform granulation to obtain a plurality of granular plastic composite materials.

When the plastic composite material of the present invention is heated to a molten state, it has good and stable fluidity and is suitable for injection molding processes with high molding requirements. Since the molding conditions such as the temperature and pressure of the plastic composite material of the present invention used in injection molding are easy to control, the yield rate of the manufactured plastic product is extremely high.

Furthermore, the plastic composite material of the present invention is suitable for application in injection molding, thus eliminating the need for subsequent processing compared to extrusion molding, thereby reducing production costs and improving production efficiency.

Furthermore, the plastic composite material of the present invention does not need to add wood powder, and the finished product does not absorb water, is suitable for humid environments, and is installed outdoors without mold, spots or insects, and can be used for a long time. In addition, since it is made of plastic, it can be completely recycled and reused after being dismantled for a long time, which is friendly to the environment; compared with the use of synthetic plastic wood (WPC), it is difficult to completely decompose after disposal and cannot be recycled.

The following is a specific embodiment to illustrate the implementation of the present invention. People familiar with the art can easily understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different implementations. The details in this specification can also be modified and changed based on different viewpoints and applications without departing from the spirit disclosed by the present invention. In addition, all ranges and values in this document are inclusive and combinable. Any value or point within the range described in this document, such as any integer, can be used as a minimum value or maximum value to derive a lower range, etc.

The following is a more detailed description of the implementation of the present invention with reference to the drawings and component symbols, so that those skilled in the art can implement the invention accordingly after reading this specification.

The present invention provides a plastic composite material, comprising the following components in weight percentage: polystyrene (PS) 30%-85%, synthetic rubber (Styrene-Butadiene Rubber, SBR) 15%-55%, emulsion polymerized butadiene styrene rubber (ESBR) 3%-45%, and auxiliary agent 0.1%-10%.

Polystyrene is a thermoplastic plastic. As one of the components of the plastic composite material of the present invention, it has good light transmittance, hardness, processing dimensional stability, fluidity, and easy processing and dyeing; the synthetic rubber itself is a copolymer of styrene and butadiene, and has the same elasticity as natural rubber; the emulsified synthetic rubber has excellent abrasion resistance, tensile strength, tear strength, and aging resistance.

In an embodiment of the present invention, the plastic composite material further includes 0.1%-10% by weight of an auxiliary agent, wherein the auxiliary agent includes: at least one or a combination of an organic stabilizer, a coupling agent, a thermal stabilizer, a gelling accelerator, a foaming agent, and a light absorber.

Organic stabilizers are used to prevent the mixed materials from changing color or deteriorating during processing, use or recycling. Preferably, organic stabilizers include but are not limited to: calcium/zinc powder stabilizers, barium-zinc/barium-calcium-zinc powder stabilizers, barium-zinc/calcium-zinc liquid stabilizers, organic tin stabilizers, lead stabilizers, phosphorus stabilizers, and hindered phenol stabilizers.

The coupling agent is used to enhance the interface properties of the material, improve the viscosity and dispersion, and can be used as a filling material. The coupling agent includes but is not limited to chromium complex coupling agents, silane coupling agents, titanium ester coupling agents, and organic peroxide coupling agents.

Thermal stabilizers are used to prevent thermal degradation during processing and to prevent aging of products during long-term use. Preferably, thermal stabilizers include but are not limited to: tribasic lead sulfate, dibasic lead phosphite, cadmium stearate, barium stearate, magnesium stearate, zinc stearate, calcium stearate, aluminum stearate, lead stearate, di-n-octyltin maleate, S, S'-bis(isooctyl thioglycolate) di-n-octyltin, and phosphorus-based thermal stabilizers.

The gelling accelerator is used to accelerate the vulcanization reaction in the rubber. Preferably, the gelling accelerator includes, but is not limited to, 1,3-diphenylguanidine, tetraethylthiuram disulfide, copper dimethyldithiocarbamate, N-cyclohexyl-2-benzothiazole sulfenamide, N,N'-dicyclohexyl-2-benzothiazole sulfenamide, tetramethylthiuram disulfide, N-tert-butyl-2-benzothiazole sulfenamide, N-oxydiethyl-2-benzothiazole sulfenamide, dibenzothiazole disulfide, 2-mercaptobenzothiazole, and ultra-low molecular weight polystyrene.

The foaming agent is used to generate continuous or discontinuous micropores in plastics. Preferably, the foaming agent includes but is not limited to azodicarbonamide, 2,2'-azobisisobutyronitrile, diisopropyl azodicarboxylate, barium azodicarboxylate, diethyl azodicarboxylate, azoaminobenzene, N,N'-dinitrosopentamethylenetetramine, N,N'-dimethyl-N,N'-dinitrosoterephthalamide, benzenesulfonylhydrazine, p-toluenesulfonylhydrazine, and sodium bicarbonate.

Light absorbers are used to inhibit or slow down the photodegradation or photoaging of plastics caused by absorbing ultraviolet light, thereby extending the use and storage life of plastic products. Preferably, light absorbers include, but are not limited to, 2,2'-dihydroxy-4-methoxybenzophenone, 2-(2-hydroxy-3,5-di-tert-butylphenyl)-5-chlorobenzotriazole, 4-tert-butylphenyl salicylate, and 2-ethylhexyl-2-cyano-3,3-diphenylacrylate.

Furthermore, the present invention provides a preparation process of a plastic composite material, as shown in FIG1.

Step S110, crushing the recycled materials and/or scraps containing polystyrene, synthetic rubber, and emulsified synthetic rubber;

Step S120, weighing 30%-85% of the polystyrene, 15%-55% of the synthetic rubber, and 3%-45% of the emulsified synthetic rubber according to the weight percentage of each component of the composite material;

Step S130, mixing the weighed polystyrene, the synthetic rubber, and the emulsified synthetic rubber to obtain a mixed material;

Step S140, feeding the mixed material into the main feed port, and feeding 0.1-10% of the auxiliary agent into the side feed port for granulation to obtain a plurality of granular plastic composite materials; and

Preferably, in step S110, polystyrene comes from recycled plastic waste or waste and scraps left over from plastic processing; synthetic rubber and emulsified synthetic rubber come from recycled rubber waste or waste and scraps left over from rubber processing.

In the embodiments of the present invention, whether it is plastic recycled materials and/or waste materials, or rubber recycled materials and/or waste materials, they are not limited to their shapes, that is, the present invention can crush plastic recycled materials and/or waste materials, and rubber recycled materials and/or waste materials in various shapes, such as strips, blocks, shavings, etc.

Then, the recycled materials and/or scraps are crushed by a crusher, and the crushed recycled materials or scraps containing polystyrene are separated from other plastics, and the crushed recycled materials or scraps of synthetic rubber and emulsified synthetic rubber are separated from other rubbers. In this way, the mixed material using recycled materials and/or scraps will not contain unnecessary other types of plastics and rubbers, making the types of materials in the mixed material simple.

Preferably, after obtaining the mixed material, in step S140, the mixed material containing 30%-85% polystyrene, 15%-55% synthetic rubber, and 3%-45% emulsified synthetic rubber is fed into the main feed port, and then 0.1%-10% of the auxiliary agent is fed into the side feed port. Specifically, between 0.1%-10% of the organic stabilizer, between 0.1%-5% of the coupling agent, between 0.1%-3% of the thermal stabilizer, between 0.1%-10% of the gelling accelerator, between 0.1%-3% of the foaming agent, and between 0.1%-3% of the light absorber are added into the side feed port.

In the embodiment of the present invention, the light absorber used absorbs ultraviolet light of 300nm-325nm. Preferably, it absorbs ultraviolet light of 313nm-318nm. The use of light absorbers in the above wavelength range can significantly improve the fission of polystyrene during the production process and the use process.

The mixed material and the auxiliary agent are respectively fed into an extruder, and after being melt-mixed, they are extruded from a die. In the embodiment of the present invention, a cooling and shaping system is also included, which can extrude the melt-mixed material from the die, cut out ester particles through a rotary cutter, and the ester particles are cooled and shaped due to the sudden drop in temperature. In this way, a plurality of granular plastic composite materials are obtained.

Preferably, the method further comprises a screening machine, which filters and screens ester particles of different particle sizes by vibration, and reduces excess powder in the ester particles.

Through the above preparation method, the plurality of plastic composite materials are further fed into an injection molding machine, heated to a molten flow state, and pressurized to eject the plurality of molten polymer raw materials from a die head into a mold, and then cooled and formed to produce a plastic finished product.

When the plastic composite material of the present invention is heated to a molten state, it has good and stable fluidity and is suitable for injection molding processes with high molding requirements. Since the molding conditions such as the temperature and pressure of the plastic composite material of the present invention used in injection molding are easy to control, the yield rate of the manufactured plastic product is extremely high.

Furthermore, the plastic composite material of the present invention is suitable for application in injection molding, thus eliminating the need for subsequent processing compared to extrusion molding, thereby reducing production costs and improving production efficiency.

Furthermore, the plastic composite material of the present invention does not need to add wood powder, and the finished product does not absorb water, is suitable for humid environments, and is installed outdoors without mold, spots or insects, and can be used for a long time. In addition, since it is made of plastic, it can be completely recycled and reused after being dismantled for a long time, which is friendly to the environment; compared with the use of synthetic plastic wood (WPC), it is difficult to completely decompose after disposal and cannot be recycled.

The above embodiments are only illustrative and not intended to limit the present invention. Anyone skilled in the art may modify and alter the above embodiments without violating the spirit and scope of the present invention. Therefore, the scope of protection of the present invention is defined by the scope of the patent application attached to the present invention. As long as it does not affect the effect and implementation purpose of the present invention, it should be covered by the disclosed technical content.

S110: step S120: step S130: step S140: step

FIG. 1 is a schematic diagram of the preparation process of the plastic composite material provided in an embodiment of the present invention.

S110: Step

S120: Step

S130: Step

S140: Step

Claims (9)

A plastic composite material is made of the following components in percentage by weight: 30%-85% polystyrene, 15%-55% synthetic rubber, 3%-45% emulsified synthetic rubber, and 0.1%-10% auxiliary agent. The plastic composite material as described in claim 1, wherein the auxiliary agent includes at least one or a combination of an organic stabilizer, a coupling agent, a thermal stabilizer, a gelling accelerator, a foaming agent, and a light absorber. The plastic composite material as described in claim 2, wherein the weight percentage of the organic stabilizer is 0.1%-10%, the weight percentage of the coupling agent is 0.1%-5%, the weight percentage of the thermal stabilizer is 0.1%-3%, the weight percentage of the gelling accelerator is 0.1%-10%, the weight percentage of the foaming agent is 0.1%-3%, and the weight percentage of the light absorber is 0.1%-3%. The plastic composite material as described in claim 1, wherein the polystyrene comes from recycled materials or scraps of plastic waste. The plastic composite material as described in claim 1, wherein the synthetic rubber and/or the emulsified synthetic rubber is derived from recycled materials or scraps of rubber waste. The plastic composite material as described in claim 4 or 5, wherein the recycled material and/or the scrap material has at least one of the shapes of strips, blocks, and shavings. The plastic composite material as described in claim 2, wherein the light absorber absorbs ultraviolet light of 300nm-325nm. The plastic composite material as described in claim 7, wherein the light absorber absorbs ultraviolet light of 313nm-318nm. A method for producing a plastic composite material using any one of claims 1 to 8, crushing recycled materials and/or scraps containing polystyrene, synthetic rubber, and emulsified synthetic rubber; weighing 30%-85% of the polystyrene, 15%-55% of the synthetic rubber, and 3%-45% of the emulsified synthetic rubber according to the weight percentage of each component of the composite material; mixing the weighed polystyrene, synthetic rubber, and emulsified synthetic rubber to obtain a mixed material; feeding the mixed material into the main feed port, and feeding 0.1-10% of the auxiliary agent into the side feed port, granulating, and obtaining a plurality of granular plastic composite materials.