KR20180056430A - a plastic pellet forming method with SEBS in artificial turf - Google Patents

Abstract

The present invention relates to a method of recycling a waste artificial turf filler. The purpose of the present invention is to provide a method which is capable of recycling the waste artificial turf filler (SEBS) as a method of manufacturing plastic pallets using the SEBS according to the present invention. The method according to the present invention comprises: a mixing step of mixing 10 to 20 parts by weight of an active additive and 30 to 90 parts by weight of the SEBS (styrene-ethylene-butylene-styrene) with respect to 100 parts by weight of polypropylene; a remixing step of injecting 10 to 20 parts by weight of water into a mixture passing through the mixing step, and mixing the mixture with water for 20 to 40 minutes by using a stirrer; an injection step of injecting a mixture passing through the remixing step into a plastic injection machine to inject the mixture by using a screw rotated to a rotation speed of 100 to 300 rpm at 200 to 250°C; a cooling step of cooling a molten mixture discharged through the injection step in water of 40 to 50°C; and a cutting step of cutting a mixture passing through the cooling step to 5 to 20 mm.

Description

Technical Field [0001] The present invention relates to a plastic pellet forming method using SEBS in artificial turf,

The present invention relates to a method for producing plastic pellets using waste artificial grass filler (SEBS), and more particularly, to a method for recycling SEBS, which is widely used as a filler for artificial turf, as plastic pellets.

Artificial turf has been developed for use in areas where it is difficult to grow natural grass, such as in the open-aired area to the north of a tall building with very limited sunshine hours.

These artificial turf are generally made of synthetic fibers. They are made of basic polypropylene (PP), polyethylene (PE), nylon (pile), and natural grass, (Rubber powder) which is sprayed for the purpose of preventing an injury, a silica sand and a crushed stone layer capable of supporting an artificial turf, and a surface treatment layer for fixing an artificial turf.

Particularly, in the case of fillers, SBR (Styrene Butadiene Rubber), SBS (Styrene-Butadiene-Styrene), SEBS (Styrene-Ethylene-Butylene-Styrene), EPDM rubber (Ethylene Propylene Diene Monomer ) Are mainly used, and most of them are based on fossil fuels.

Recently, there has been a controversy about the harmfulness to such fillers. In general, the fillers generated in disassembly of artificial turf are not decomposed even after 100 years of disposal through landfill. Most of them are used as a heat source for incineration because of the possibility of discharging the material. However, this method also requires an environmentally appropriate treatment method for discharging carbon dioxide.

In Korea, artificial turf is a kind of artificial turf that is used for athletic field, soccer field, hockey field baseball field, cycling field, tennis court, wrestling field, simple athletic field (village sports facility), gymnasium (Gogi gymnasium, There are about 20,000 places to be divided into the shooting range, the national archery, the two countries, the equestrian track, the golf driving range, the canoeing yard, the yacht yard, the ice rink, the snowing stadium and other facilities. .

It is estimated that artificial turf is estimated to be about 3,000 tons in 2016 and about 20,000 tons in case of filling material in the data of artificial turf generation data of national schools and public athletic facilities in 2016. Considering that the artificial turf life is about 7 years, , The same amount of artificial turf and filler will be generated over the next 10 years.

Therefore, considering the environmental aspect, it is necessary to approach from the viewpoint of recycling the filler material in the present filler material processing method which is treated by the incineration heat source, and the technology which can be recycled as a product having the same quality as the currently utilized product Development is needed.

Prior art related to the recycling of artificial turf is filed by the Korean Intellectual Property Office, Application No. 10-2011-0061657 (filed on June 24, 2011), Application No. 10-2011-0096519 (filed on September 23, 2011) have.

Recently, in the polystyrene-based TPE industry, the SEBS system has been increasingly used due to improvement in weatherability and heat resistance, which are shortcomings of the SBS system. However, these prior arts do not have a technology for recycling SEBS (Styrene-Ethylene-Butylene-Styrene) It is true.

A method for producing a plastic pellet using a waste artificial grass filler (SEBS) according to the present invention aims at providing a method for recycling waste artificial grass filler (SEBS).

The method for producing plastic pellets using the waste artificial grass filler (SEBS) according to the present invention comprises 10 to 20 parts by weight of an active additive, 30 to 50 parts by weight of a styrene-ethylene-butylene-styrene (SEBS) A mixing step of mixing 10 to 20 parts by weight of water into the mixture after the mixing step and mixing for 20 to 40 minutes using an agitator; A cooling step of cooling the molten mixture discharged through the injection step in water of 40 to 50 degrees Celsius; cooling the molten mixture discharged through the injection step in water of 40 to 50 degrees Celsius; And a cutting step of cutting the mixture after the step to 5 to 20 mm.

Here, the active additive is one of pearlite and fired tin.

The method of producing plastic pellets using the waste artificial grass filler (SEBS) according to the present invention is advantageous in that SEBS used as a synthetic grass filler is recently produced in the form of plastic pellets and can be recycled as a plastic product having similar performance to polypropylene have.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a method for producing a plastic pellet using waste artificial grass filler (SEBS) according to a preferred embodiment of the present invention. FIG.
FIG. 2 is a photograph of a test specimen prepared using a pellet produced by a method of manufacturing a plastic pellet using a waste artificial grass filler (SEBS) according to a preferred embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The thermoplastic elastomer is an elastomer such as rubber. The thermoplastic elastomer can be divided into six products such as a styrene type, a PVC type, an olefin type, a polyester type, a polyamide type and a urethane type. , SBS, SIS, and SEBS in soft phase butadiene, polyisoprene, polyethylene, and polybutylene.

Styrene-butadiene styrene (-SBS-), SIS-based styrene-polyisoprene-styrene (-S-PI-S-), SEBS-based (styrene-polyethylene / polybutylene- styrene-) .

Such SEBS is known as excellent elastic recovery property and non-toxic product, and has recently been used as an artificial turf filler material, and a technique for reprocessing synthetic turf is required when the life time of artificial turf is exhausted.

In the present invention, it is intended to provide a method for recycling such SEBS as a plastic product having a performance similar to that of a PP (polypropylene) product.

1 is a block diagram showing a method of manufacturing a plastic pellet using a waste artificial grass filler (SEBS) according to a preferred embodiment of the present invention.

As shown in FIG. 1, the method of manufacturing a plastic pellet using a waste artificial grass filler (SEBS) according to the present invention includes a mixing step S100, a remixing step S200, an injection step S300, a cooling step S400, And a cutting step S500.

First, in the mixing step (S100), 10 to 20 parts by weight of the active additive and 30 to 90 parts by weight of styrene-ethylenic double bond styrene (SEBS) are mixed with 100 parts by weight of the polypropylene.

When the SEBS exceeds 90 parts by weight, continuous injection is not performed in the injection step to be described later, and when the amount is less than 30 parts by weight, there arises a problem that commercial recycling costs are excessively required. Which increases production costs and undermines SEBS recycling efficiency.)

Next, the active additive will use either pearlite or calcined tin, and this active additive will be used for the purpose of minimizing porosity formation during mixing, allowing homogeneous mixing, and enhancing the binding force between PP and SEBS .

10 to 20 parts by weight of water is added to the mixture obtained through the mixing step (S100), and the mixture is subjected to a mixing step (S200) in which the mixture is mixed for 20 to 40 minutes using an agitator.

The water re-mixing process for such wet mixing has a problem in that uniform stirring is not performed when stirring is performed for 20 minutes or less.

The mixture having been subjected to the re-mixing step (S200) is injected into a plastic injection machine and then subjected to an injection step (S300) in which the mixture is injected using a screw rotating at 200 to 250 degrees centigrade and 100 to 300 RPM.

The injection step S300 is a step of melting the mixture through the re-mixing step and injecting the mixture into a strand through a screw injector. The molten mixture discharged through the injection step S300 is injected in a molten state of 40 to 50 And then solidified through a cooling step (S400) in which the water is cooled in water.

In the cooling step (S400), the object water in the form of noodles (or yarn) discharged through the injection step is allowed to pass through the cooling bath to solidify the object.

Finally, the mixture having undergone the cooling step (S400) is subjected to a cutting step (S500) in which the mixture is cut into a uniform size of 5 to 20 mm.

The pellet after the cutting step S500 is used as a raw material for molding the plastic product.

As for various embodiments of the plastic pellet manufacturing method using the waste artificial grass filler (SEBS)

≪ Example 1 >

10 parts by weight of an active additive and 60 parts by weight of a waste synthetic artificial grass filler (SEBS: Styrene-Ethylene Butyrene-styrene) were mixed with 100 parts by weight of polypropylene, and 10 parts by weight of water was re- And then molded into a plastic product.

FIG. 2 is a photograph of a test specimen made using a pellet produced by a method of manufacturing a plastic pellet using a waste artificial grass filler (SEBS) according to a preferred embodiment of the present invention.

The test results of the product shown in FIG. 2 by the test method of ASTM (American Society for Testing and Materials) are shown in Table 1 below.

Specifically, it can be understood that the elastic strength is sharply reduced when the SEBS is increased by a certain amount or more (SEBS 60 parts by weight or more relative to 100 parts by weight of polypropylene), so that it is difficult to apply the composition as a plastic product.

It can be confirmed that the other properties are significantly reduced when the SEBS content is 60 parts by weight or more.

PHYSICAL TEST METHOD TYPICAL VALUE UNIT Melt Flow Index, 190 DEG C, 2.16 kg ASTM D1238 2.0 g / 10 min Izod Impact ASTMD256 9.3 to 10 gf.cm / cm Tensile strength ASTM D638 123 ~ gf / cm 2 elongation at break ASTM D638 29  % Yield ASTM D638 125 gf / cm 2 Flexural modulus ASTM D790 7,700 gf / cm 2

≪ Example 2 >

10 parts by weight of an active additive and 30 parts by weight of a waste synthetic artificial grass filler (SEBS: Styrene-Ethylene Butyrene-styrene) were mixed with 100 parts by weight of polypropylene, re-alloyed with 10 parts by weight of water, And then molded into a plastic product.

PHYSICAL TEST METHOD TYPICAL VALUE UNIT Melt Flow Index, 190 DEG C, 2.16 kg ASTM D1238 5.68 g / 10 min Izod Impact ASTMD256 7.0 to 7.6 gf.cm / cm Tensile strength ASTM D638 125 ~ gf / cm 2 elongation at break ASTM D638 26  % Yield ASTM D638 136 gf / cm 2 Flexural modulus ASTM D790 8,400 gf / cm 2

≪ Example 3 >

10 parts by weight of an active additive and 60 parts by weight of a waste synthetic artificial grass filler (SEBS: Styrene-Ethylene Butyrene-styrene) were mixed with 100 parts by weight of polypropylene, and 10 parts by weight of water was re- And then molded into a plastic product.

As compared with Example 2, it can be confirmed that the increase in the elastic strength is not large and the strength performance is almost similar to that of the polypropylene product.

PHYSICAL TEST METHOD TYPICAL VALUE UNIT Melt Flow Index, 190 DEG C, 2.16 kg ASTM D1238 7.8 g / 10 min Izod Impact ASTMD256 6.3 to 7.1 gf.cm / cm Tensile strength ASTM D638 130 ~ gf / cm 2 elongation at break ASTM D638 30  % Yield ASTM D638 140 gf / cm 2 Flexural modulus ASTM D790 8,500 gf / cm 2

As described above, the present invention provides a method of manufacturing a plastic pellet using a waste artificial grass filler (SEBS) as a main technical idea, and since the above-described embodiment is only one embodiment with reference to the drawings, The true scope should be determined by the claims.

S100: mixing step
S200: Re-mixing step
S300: injection step
S400: cooling step
S500: Cutting step

Claims (2)

Mixing 10 to 20 parts by weight of an active additive and 30 to 90 parts by weight of a waste synthetic artificial grass filler (SEBS: Styrene-Ethylene Butyrene-styrene) per 100 parts by weight of polypropylene;
A mixing step of adding 10 to 20 parts by weight of water to the mixture after the mixing step and mixing the mixture for 20 to 40 minutes using an agitator;
Injecting the mixture obtained through the re-mixing step into a plastic injection machine and injecting the mixture using a screw rotated at 200 to 250 degrees centigrade and 100 to 300 RPM;
A cooling step of cooling the molten mixture discharged through the injection step in water of 40 to 50 degrees Celsius;
And a cutting step of cutting the mixture having passed through the cooling step to 5 to 20 mm. The method for manufacturing a plastic pellet using the waste artificial grass filler (SEBS).
The method according to claim 1,
The active additive may comprise,
Pearlite, and fired tin. The method of manufacturing a plastic pellet using waste artificial grass filler (SEBS).

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