KR20030093546A - Waste plastic/ground rubber tire composite and forms using the same - Google Patents

Abstract

PURPOSE: Provided is waste plastic/ground rubber tire complex material having high elasticity and excellent in tensile strength, flexural strength, and impact absorption, which can be used for engineering and construction material like waterways, drain pipes, and septic tanks and median strips of roads. CONSTITUTION: The waste plastic/ground rubber tire complex material is obtained by a process comprising the steps of: mixing 10-50wt% of ground rubber tire powder to waste polyethylene resin; adding 5-20wt% of polypropylene as an organic additive and 5-20wt% of an adhesive resin comprising a polyolefin resin and maleic anhydride in the ratio of 1:0.3-0.4 to the waste polyethylene/ground rubber tire mixture; mixing and melting at 130-180deg.C. And the molded product of the waste plastic/ground rubber tire is produced by injecting or extrusion-molding the complex material.

Description

Waste plastic / ground rubber tire composite and forms using the same}

The present invention relates to a waste plastic (Waste Plastic) / waste rubber (Ground Rubber Tire; GRT) composite material and a molding obtained by using the same, more specifically, by mixing 10 to 50% by weight of waste tire powder to waste polyethylene A waste polyethylene / waste tire mixture is obtained, and 5-20 wt% of an organic additive polypropylene, 5-20 wt% of a polyolefin resin and a viscous resin mixed with maleic anhydride 1: 0.3 to 0.4 are added, mixed and melted. The present invention relates to a composite material obtained by molding, and a molded article having a plate-like or tubular shape obtained by injection, extrusion, or molding thereof.

Waste plastics and waste tires are not direct malignant wastes such as being inhaled by the human body or polluting the soil, but are relatively easy to recover. Various researches have been conducted in the field, and especially in the developed countries, efforts are being made to continuously generate demand through environmentally friendly recycling, which can lead to the exponential increase of such waste resources.

In the past, landfilling was mainly used as a method of treating waste tires, but this is not only a large volume of waste tire, which occupies much of the landfill volume of the land, but also it takes a long time to completely decompose due to hard decomposability. There are problems such as risks and pollution of the soil. Currently, waste tires are recycled for processing and heat use. However, among these, the heat use method that exceeds 65.2% of the waste tire recycling rate is not suitable for continuous utilization as it generates air pollutants such as SO _x , NO _x and HCl when the waste tire is incinerated. Therefore, continuous research is being carried out as technology development through waste tire powder processing method that not only induces continuous demand for waste tire powder but also guarantees convenience in processing and transportation is recognized as the most efficient way. It is also used as a construction material, such as to manufacture sidewalk blocks and rubber bricks.

On the other hand, the amount of waste plastic is increasing year by year, but there is a limit to the separation of mixed waste plastic and mixed use with other materials, the recycling rate is low until now due to the fall of processing technology. In the case of plastics, polypropylene (PP) and high density polyethylene (HDPE) account for 54.8% of total waste plastics. Currently used plastic recycling methods are divided into three types: simple regeneration (mixed regeneration), heat use method and chemical decomposition (emulsification treatment). Among them, heat use method generates environmental pollution emission sources and induces chemical decomposition. Regeneration method through opaque treatment process is uncertain due to rising labor cost, high price of sorting machine and uncertainty of its efficiency. Therefore, the most preferable of these methods is a mixed regeneration method. Currently, composite materials using plastic and powdered waste tires have been developed, and recycling to new uses has been attempted not only in Korea but also in many countries such as the US and Australia. The research trends in Korea and abroad are as follows.

Blood in the United States. P. Rajalingam and W. this. We Baker examines the properties of linear low density polyethylene (LLDPE) and high density polyethylene (HDPE) mixed with waste tires and uses styrene block copolymers, EVA (ethylene-co-vinyl acetate) and EAA (ethylene- When the coupling agent (co-acrylic acid) and the like (coupling agent) is added it was confirmed that the impact energy (impact energy) of the composite can be improved. Also, this. L. Baudrieguez (E. L. Bodriguez) has confirmed that the strength of the composite is improved by adding various types of silane coupling agent and sand to cryogenic waste tire (CGR) and polyester composite.

In Australia, this is a government-sponsored project (GIRD; Generic Industry Research & Development-Project No. 150657), which is a combination of industry, universities (RMIT, Polymer Technology Centre) and research institutes (CSIRO Division of Building, Construction & Eng.). The company is speeding up the development of materials and research is underway to use waste tires as fillers for polyolefin moldings in Canada.

In Korea, researches using waste tires and plastics have been continuously conducted, and Korean Patent No. 0149845 and Korean Patent No. 0180216 mix waste tire powder and plastic resin, and improve the fluidity of ethyl-vinyl acetate polymer. , Composite material prepared by adding cumene hydroperoxide or dicumyl peroxide (DCP) as a crosslinking agent for high temperature crosslinking before extrusion and ethylene-propylene-diene polymer for enhanced compatibility to the mixture A composition, a manufacturing method, and a molding manufactured by using the same are disclosed, but this method focuses on the use of building materials such as sidewalk blocks and flooring materials through injection molding, rather than the production of perfusion through extrusion molding. Physical properties such as tensile strength and impact strength of the molded molding There is a problem that is difficult to put to practical use as a substitute.

As described above, research on the development of waste plastic / waste tire composite materials has been conducted at home and abroad, but these have not been put to practical use. Therefore, there is an urgent need for the development of waste plastic / waste tire composite materials for the efficient recycling of waste tires and waste plastics, which are rapidly increasing, and there is a demand for the development of a method of mixing waste plastics and waste tires.

Therefore, in the present invention, as a result of the development of excellent composite materials mixed with waste plastics and waste tires and researches for obtaining molded products thereof, 10 to 50 wt% of waste tires are mixed with waste polyethylene, and poly-organic additives are added thereto. By adding, mixing, and melting a propylene resin, a polyolefin resin, and a maleic anhydride mixed at 1: 0.3 to 0.4, a waste plastic / waste tire composite material having excellent physical properties such as tensile strength and bending strength could be obtained. This invention was completed.

Accordingly, an object of the present invention is to increase the recycling rate of waste tires and waste plastics that are incinerated or buried to cause environmental pollution, and to provide a waste plastic / waste tire composite material having excellent physical properties.

Another object of the present invention is to provide a molded article manufactured using the composite material.

Waste plastic / waste tire composite material of the present invention for achieving the above object is mixed with waste tire powder 10 to 50% by weight of waste polyethylene, 5 to 20 weight of polypropylene as an organic additive to the waste polyethylene / waste tire mixture It is obtained by mixing and melting at a temperature of 130 to 180 ° C. by adding 5 to 20% by weight of a tackifying resin in which%, polyolefin resin and maleic anhydride are mixed at 1: 0.3 to 0.4.

In order to achieve the above another object, the molding of the present invention is obtained by injection or extrusion of a waste plastic / waste tire composite material prepared according to the above method.

Hereinafter, the present invention will be described in more detail.

As described above, in the present invention, 10 to 50% by weight of waste tires are mixed with waste polyethylene, and there is added a tacky resin containing polypropylene, an polyolefin resin, and maleic anhydride 1: 0.3 to 0.4 as an organic additive. The present invention relates to a waste plastic / waste tire composite material produced by mixing and melting at 130 to 180 ° C. and a molding obtained by injection or extrusion molding the same.

The waste plastics of the present invention are pelletized by melting waste vinyl, and are high density polyethylene, linear low density polyethylene, or low density polyethylene, which occupy most of the waste plastic, and preferably high density polyethylene.

The waste tire of the present invention differs depending on the manufacturer, but the main component is 25 to 45% natural rubber, 40 to 45% styrene butadiene rubber, 10 to 15% butadiene rubber, 10 to 13% Solvent solubles such as a crosslinking agent component, sulfur, zinc oxide and carbon black, and ground to -40 mesh were used.

The waste plastic / waste tire composition according to the present invention is intended to replace plastic molding by mixing waste tire with 10 to 50% by weight of waste polyethylene, and when the amount of the waste tire is added is less than 10% by weight, there is no effect of waste tire recycling. If it exceeds 50% by weight, the rubber properties are close.

In addition, in the present invention, in order to improve the physical properties of the composition, a pressure-sensitive resin obtained by mixing maleic anhydride with polypropylene which is a commercially available organic additive and a polyolefin resin is used. The physical properties of the polypropylene has a melt index of 8.5 g / 10 min, a softening point of 152 ° C., a tensile strength of 350 kgf / cm 2, and the physical properties of the tacky resin mixed with maleic anhydride in the polyolefin with a melting index of 4.5 g / 10 min, a softening point of 95 ° C., Tensile strength is 230 kgf / cm 2. The amount of the polypropylene which is the organic additive is 5 to 20% by weight, preferably 5 to 15% by weight, based on the waste polyethylene / waste tire mixture, and when the amount of the polypropylene is less than 5% by weight, almost no improvement in physical properties is observed. If it exceeds 20% by weight, there is a problem that the compatibility with the waste tire is lowered and the physical properties of the molded product is lowered. On the other hand, the addition amount of the adhesive resin mixed with maleic anhydride to the polyolefin resin is 5 to 20% by weight, preferably 10 to 20% by weight, less than 5% by weight of the role as the adhesive resin is insignificant, 20% by weight If it exceeds, the improvement of physical properties is insignificant, but it is relatively expensive, so there is a problem in economic efficiency because it does not meet the purpose of recycling waste. The polypropylene has the best compatibility among polyethylene and plastics, and particularly, has excellent stress crack resistance and mechanical properties, thereby improving tensile strength and compressive strength, and mixing maleic anhydride with polyolefin resin. One adhesive resin is a key polymer with a polar (reactive) group, which promotes commercialization with plastics, thereby increasing adhesion in the manufacture of waste plastic / waste tire mixtures, and serves as an interfacial strengthening, and facilitates kneading between two materials. This will increase the strength.

According to the present invention, waste tire powder (-40 mesh) is mixed with 10 to 50% by weight of waste polyethylene pellets, and 5 to 20% by weight of polypropylene, polyolefin-based resin and maleic anhydride are used in the waste polyethylene / waste tire composition. : 5 to 20% by weight of the adhesive resin mixed with 0.3 to 0.4 was added, and the mixed composition was introduced into a hopper (extruder inlet) to be injected or extruded.

The mixture introduced into the hopper is stirred and extruded through a screw in a heated extruder, wherein the temperature inside the extruder is preferably 130 to 180 ° C.

More specifically, the extrusion molding process waste polyethylene / waste tires by primary mixing and melting using a twin screw to make pellets, polypropylene and polyolefin-based organic additives to the pellets The adhesive resin which mixed maleic anhydride with resin was secondary-mixed and melted using the single screw, and the moldings, such as plate flow and a perfusion, were obtained.

The waste polyethylene / waste tire composite material prepared according to the present invention and the molded product obtained by using the same were superior in terms of physical properties such as tensile strength and flexural strength as compared with the conventional composite material in which waste plastic and waste tire were mixed.

Hereinafter, the present invention will be described in more detail with reference to the following Examples, but the scope of the present invention is not limited to the following Examples.

Example 1

Both waste plastics and waste tires were purchased from a resource recycling project. Waste plastics were collected by washing and drying waste vinyl high density polyethylene (HDPE), and then melted and pelletized. The pellets were 2 to 4 mm in size. Was -40mesh powder. In addition, polypropylene (PP) is a product of Daehan Emulsification Standard 4017, and the adhesive resin which mixed maleic anhydride with polyolefin resin used the adpoly EM-550 of Honam Petrochemical.

10 to 50% by weight of waste tires are mixed with the waste polyethylene in the composition shown in Tables 1a and 1b, and 5 to 20% by weight of an organic additive polypropylene and 5 to 20% by weight of an adpoly are added and mixed. Put it in. The temperature inside the extruder was extruded to 130 to 180 ° C. to extract tubular moldings.

Example 2

The tubular moldings obtained in accordance with Example 1 were prepared from specimens of tubes having an outside diameter of 17 mm, a thickness of 2.0 mm, and a nominal diameter of 10 according to KS M 3407. The specimens were measured for tensile strength and flexural strength by using a universal testing machine (UTM), and are shown in Tables 1a-b.

Waste Polyethylene / Waste Tires Polypropylene (%) Ad poly (%) Tensile Strength (㎏f / ㎠) Flexural Strength (㎏f / ㎠) 100/0 · · 191.9 87.7 90/10 0 · 152.9 71.8 5 · 157.6 72.2 10 · 165.7 76.7 15 · 158.7 77.8 20 · 142.2 74.6 · 0 152.9 71.8 · 5 155.6 72.7 · 10 158.0 73.7 · 15 159.0 74.0 · 20 159.5 71.9 5 5 183.4 88.0 10 10 194.9 81.6 80/20 0 · 130.1 52.7 5 · 131.0 55.3 10 · 131.1 57.8 15 · 127.2 61.3 20 · 116.6 64.7 · 0 130.1 52.7 · 5 131.0 53.0 · 10 132.1 53.8 · 15 132.2 51.9 · 20 133.1 50.7 5 5 133.4 69.4 10 10 152.5 76.7 70/30 0 · 101.4 39.2 5 · 102.8 40.4 10 · 108.1 43.2 15 · 100.3 44.2 20 · 91.0 48.9 · 0 101.4 39.2 · 5 101.5 40.5 · 10 102.3 41.8 · 15 102.8 41.6 · 20 103.5 40.8 5 5 116.3 46.2 10 10 124.1 57.1

Waste Polyethylene / Waste Tires Polypropylene (%) Ad poly (%) Tensile Strength (㎏f / ㎠) Flexural Strength (㎏f / ㎠) 60/40 0 · 90.3 31.7 5 · 93.5 32.4 10 · 94.1 33.5 15 · 87.4 35.9 20 · 80.1 39.9 · 0 90.3 31.7 · 5 91.2 32.3 · 10 93.7 33.1 · 15 97.2 35.8 · 20 102.7 37.9 5 5 97.3 35.8 10 10 103.5 42.6 50/50 0 · 76.6 24.2 5 · 74.1 25.3 10 · 74.8 27.2 15 · 73.7 27.4 20 · 71.4 32.2 · 0 76.6 24.2 · 5 76.9 24.9 · 10 77.2 28.8 · 15 79.8 27.2 · 20 79.4 27.6 5 5 78.4 28.5 10 10 81.7 35.3

As can be seen from Table 1a-b, the tensile strength and bending compared with the case where the addition of the polypropylene of the organic additive or the adpoly of the adhesive resin mixed with maleic anhydride to the polyolefin-based resin is not added It was confirmed that the strength was improved, especially when the polypropylene and the ad poly was used at the same time, it showed more excellent physical properties.

As described above, the composite material prepared according to the present invention and a molded product thereof are a low-cost waste tire mixed with waste plastic, and a polypropylene and an polyolefin resin, which is an organic additive, are mixed with maleic anhydride. By adding, it was possible to economically obtain a composite material having superior physical properties than conventional molded products using waste plastics and waste tires, which can be commercialized in various injection and extrusion products such as drain pipes, sewers, septic tanks, and central road separators. will be.

Claims (6)

10 to 50% by weight of the waste tire powder is mixed with the waste polyethylene resin, and 5 to 20% by weight of the organic additive polypropylene, polyolefin-based resin and maleic anhydride are mixed at a ratio of 0.3 to 0.4 to the waste polyethylene / waste tire mixture. A waste plastic / waste tire composite material, which is obtained by adding 5 to 20% by weight of one adhesive resin and mixing and melting at a temperature of 130 to 180 ° C. The composite material of claim 1, wherein the polypropylene has a melt index of 8.5 g / 10 min, a softening point of 152 ° C., and a tensile strength of 350 kgf / cm 2. The composite material according to claim 1, wherein the polypropylene is added in an amount of 5 to 15% by weight. The composite material according to claim 1, wherein the amount of the adhesive resin added is 10 to 20% by weight. Waste plastic / waste tire molding, characterized in that produced by injection or extrusion molding the composite material according to any one of claims 1 to 4. 5. The molding according to claim 4, wherein the waste plastic / waste tire molding is a drain, a sewer pipe, a septic tank, or a road central separator.