KR100350547B1 - Manufacturing process for sponge using used plastics and foamed scraps - Google Patents

Abstract

In the present invention, 10 to 90 parts of sponge scrap (EVA, PP, PE) as a base resin, 10 to 80 parts of waste plastic, 0 to 10 parts of binder polymer are crushed and mixed, and 1 to 5 parts of plasticizer and 0.1 to 10% of crosslinking agent as a member. A sponge scrap foam composition obtained by mixing 5 parts, 1 to 15 parts of foaming agent and 4 to 40 parts of flame retardant, kneading, molding into a sheet, and heating and pressing in a press. According to the present invention, foams which can be used in various fields In particular, in the case of using the invention foam as a sandwich panel, the flexural strength is higher than that of the existing products (PU products and polystyrene products), so that the panel thickness can be made relatively thin and light, and the production cost can be reduced. .

Description

Foam composition using sponge scrap and waste plastic and manufacturing method of the foam {Manufacturing process for sponge using used plastics and foamed scraps}

The present invention relates to a foam composition using sponge scrap and waste plastics and a method for producing the foam.

Sponge scrap and waste plastics are both substances that produce dioxins upon incineration. However, among these waste resources, waste plastics have been used as some recycling resources relatively early, but the treatment of sponge scrap is mostly dependent on incineration due to the lack of recycling technology.

Sponge scrap is a by-product of the footwear industry or the automobile industry, and the waste stream is discharged from large production facilities, and it is easy to collect and identify the composition of the resin. However, since waste plastics are released from the disposal or production facilities of various products such as food packaging containers, beverage packaging containers, toys, household goods, and home appliances, it is difficult to identify plastic components and most of them contain impurities. Cleaning is inevitable.

Foaming techniques for plastics include US Pat. Nos. 3,959,189 and 4,427,059. Polyolefin resins, polyethylene, polypropylene and foams of various olefin copolymers not only have excellent elasticity, flexibility, abrasion resistance, chemical resistance and electrical properties, but the polystyrene foams are rigid, whereas the mechanical properties of these foams are semi-flexible. It is widely used in building materials, automobile interior materials, materials for electrical and electronic parts, and general merchandise.

While the foaming technology of the US patent is a foaming technology of a new plastic material, the foaming technology disclosed in Korean patent applications 10-1997-72401 and 10-1999-038131 is a foaming technology of reusable mixed waste plastic material. It is characterized by using.

Specifically, the waste plastic foaming technology proposed in the patent application 10-1997-72401 is a dominant resin, a polyethylene resin and a pyrolysis material obtained by thermally decomposing waste plastics in wax form under a temperature of 600-800 ° C. and nitrogen at a weight ratio of 100: 80. 2-10% by weight of azodicarbonamide blowing agent and 1-4% by weight of dicumylperoxide crosslinking agent are added thereto, followed by foaming at 205 DEG C or higher over 1-4 minutes, or as an adjuvant of the blowing agent. ZnO is added up to 2% by weight and foamed at a temperature of 130-155 ° C.

However, the foaming technology of waste plastic using the above pyrolysis material can not only use sponge scrap as waste raw material, but also require high heat and high pressure as a high-temperature foaming technology. Due to the high specific gravity of foams, the production of foams is less than that of materials, and it is pointed out that it is difficult to match the physical properties of foams according to products such as building dustproof materials and insulation panels.

It is an object of the present invention to provide a foam composition and a method for producing the foam, which make it possible to obtain a foam having a necessary specific gravity from low specific gravity to high specific gravity using sponge scrap and waste plastic (olefin type).

Specifically, a large amount of sponge scrap is released in EVA sponge (shoes industry), PP or PE sponge (automotive industry) and the like, and in particular, EVA sponge has been difficult in its processing. This invention aims at providing the waste sponge resource-recycling technique of which treatment method is urgent as mentioned above.

Another object of the present invention is the high temperature and high pressure process is introduced due to the different melting point (PE, PP, nylon, PVC, PET) of the waste plastic when the sponge is made of conventional waste plastic only, it is difficult to control the specific gravity of the foam, and as a result Existing EVA and PE sponge processes could not be applied, and the density of foams could not be increased to provide a high quality industrial foam. On the contrary, the present invention can manufacture foams in the process of using the existing sponge manufacturing process (using existing equipment), and can make products of various specific gravity, thereby broadening the field of use of the product, and in particular, the present invention provides EVA scrap. It is a technology that compensates for the shortcomings of the above-mentioned waste plastic foam by using it as a main ingredient and using waste plastic as a secondary ingredient, and it is possible to easily make building materials such as sandwich panels by making it easy to obtain low specific gravity products. Compared to products such as polystyrene and polyurethane, which are core materials for sandwich panel products, it is intended to be able to make excellent foams in terms of cost and physical properties.

1 is an illustration of a pelletization process

Figure 2 is an illustration of the pressure foaming process

3 is an exemplary view of the obtained foam

Figure 4 is an exemplary view of a state in which the panel is attached to both sides of the foam

The present invention relates to a composition of a foam and a method for producing the foam which can be used by making a foam in a sheet form using sponge scrap and waste plastic and cutting (scavenging) to a size and shape according to the use thereof. At the same time, the foams provided in this invention maintain good adhesion with panels (steel plates, tins, flat slits, stainless steel sheets) when used as core material for building sandwich panels, and can be produced with excellent foams even in mechanical strength (bending modulus). It is a foam composition which can be used, and if necessary, it is a foam composition which can impart flame retardancy and make it possible to commercialize.

This foam composition is comprised as a composition of the base resin using waste resources, and the composition of the member which concerns on the physical property of a foam.

① Composition of base resin (combination weight ratio)

Base resin is 10 ~ 90 parts of EVA, PP or PE sponge scrap, 10 ~ 80 parts of waste plastic (washed), and 0 ~ 10 parts of binder polymer (NR, SBR, CR, NBR, Acryl, etc.) -It is made by crushing (particle diameter 1-5mm)

The binder polymer may be added and mixed after grinding the sponge scrap and the plastic as shown in FIG.

Formulation range of this invention base resin

Material compounding ratio (weight number of copies)

EVA sponge scrap 10 to 90 parts

PE, PP or PVC waste plastic 80 ~ 10 parts

NR, SBR, NBR, Acryl, CR (Binder) 0 ~ 10 parts

100 copies in total

The base resin of the present invention can commercialize the base resin of the present invention by crushing the waste materials to a particle size of 1 ~ 5mm as shown in Figure 1 and mixing and molding into pellets in an extruder.

② Composition of the member (mixing ratio is weight part)

The member of the present invention is a physical composition for mixing the waste material base resin and heating and pressing to foam the base resin and at the same time to control the physical properties of the foam.

The absence of this invention is a plasticizer (Oil (Phthal acid derivatives, adipin acid derivatives, sebathin acid derivatives, malein acid derivatives, stearic acid derivatives, citric acid derivatives, epoxy derivatives, polymerization plasticizers), Sub, fatty acids and fatty acid salts, wax, etc.) 1 to 5 parts, 0.1 to 5 parts of crosslinking agents (DCP, BOP, 2,4dichloro benzoyl peroxide, butyl hydro peroxide, butyl cumyl peroxide and other organic peroxides), blowing agent (nitro compound (DPT), azo compound (AC), sodium bicarbonate, BSH (sulfonyl hydrazide), OBSH, etc.) to 1 to 15 parts.

In order to flame-retardant foam, 5 to 40 parts of flame retardant is included in the member.

Flame retardants include antimony trioxide, zinc borate, Al (OH) ₂ , Mg (OH) ₂ , CP wax, TCP, cyclic flame retardants, reactive flame retardants, and paraffin chloride.

The flame retardant also functions as a foam density regulator because it lowers the density of the foam depending on the components (particularly when the liquid phase (oil phase) is included).

An appropriate amount of pigment may be included in the foaming composition to color the foam.

Compounding range of this invention member

Flame retardant (antimony trioxide, zinc borate, Al (OH) ₂ , Mg (OH) ₂ , CP wax, TCP, retardant flame retardant, reactive flame retardant, paraffin chloride)

1 ~ 5 parts of plasticizer (Oil, Sub, fatty acid and fatty acid salt, wax, etc.)

Crosslinking agents (DCP, BOP, 2,4dichloro benzoyl peroxide, Butyl hydro peroxide,

Butyl hydro peroxide, Butyl cumyl peroxide, and other organic peroxides)

1 to 15 parts as blowing agent (DPT, AC, sodium bicarbonate, BSH, OBSH, etc.)

Correct amount of pigment (if necessary)

The waste material base resin and the member are kneaded in a roll or a closed mixer (kneader, Bunbary, etc.), molded into a sheet, heated, pressurized in a press, and depressurized to foam to obtain a sheet-like foam.

An example of the pressurized foaming process is shown in FIG. 2, the obtained foam is shown in FIG. 3, and the state in which panels are attached to both sides of the foaming is cited in FIG.

This invention can obtain the foam of the required physical properties by controlling the blending of materials as in the following examples.

Example 1

Material Compounding Weight Ratio Remarks

Base resin 100 ingredients

EVA scrap 60

Waste Plastic 30

RSS # 3 10

Stearic Acid 1 Activator

Antimony Trioxide 5 Flame Retardant

Aluminum hydroxide 15 flame retardant and filler

CP wax 3 flame retardant and processing aid

DCP 0.5 Crosslinker

AC # 7000 7 Foaming Agent

Total 131.5

Resin Blend Ratio 76%

Physical property test values of Example 1 are as follows.

Item Unit Property Remarks

Foam density g / cm3 0.05

Compressive strength kg / mm2 0.10 KSM3831, ASTM D1621-94

Absorption g / ㎠ 0.90 KSM3808, ASTM D2842-97

Combustibility see 108 KSM3808, ASTM D3014-94

Flexural Strength kg / ㎠ 0.035

Panel Flexural Strength kg / mm2 0.085 Sandwich Panel Strength

Example 2

Material Compounding Weight Ratio Remarks

Base resin 100 ingredients

EVA scrap 60

Waste Plastic 30

RSS # 3 10

Stearic Acid 1.5 Activator

TCP 10 liquid flame retardant (at the same time lowers viscosity)

Al (OH) ₂ 10 flame retardants and fillers

CP wax 3 flame retardant and processing aid

DCP 0.5 Crosslinker

AC # 7000 10 Foaming Agent

Total 135

Resin blending ratio 74%

Physical property test values of Example 2 are as follows.

Item Unit Property Remarks

Foam Density g / cm 3 0.035

Compressive strength kg / mm2 0.08 KSM3831, ASTM D1621-94

Absorption g / ㎠ 0.11 KSM3808, ASTM D2842-97

Combustibility see 168 KSM3808, ASTM D3014-94

Flexural Strength kg / ㎠ 0.030

Panel Flexural Strength kg / ㎠ 0.080 Sandwich Panel Strength

Example 3

Material Compounding Weight Ratio Remarks

Base resin 100 ingredients

EVA scrap 50

Waste Plastic 40

RSS # 3 10

Stearic Acid 1 Activator

Antimony Trioxide 5 Flame Retardant

P-HEMA 15 Flame Retardant

Mg (OH) ₂ 20 flame retardants and fillers

CP wax 3 flame retardant and processing aid

DCP 0.7 crosslinker

AC # 7000 7 Foaming Agent

Total 151.7

Resin Blend 66%

Physical property test values of Example 3 are as follows.

Item Unit Property Remarks

Foam density g / cm 3 0.12

Compressive Strength kg / ㎡ 0.12 KSM3831, ASTM D1621-94

Absorption g / ㎠ 1.00 KSM3808, ASTM D2842-97

Combustibility see 250 KSM3808, ASTM D3014-94

Flexural Strength kg / ㎠ 0.038

Panel Flexural Strength kg / mm2 0.089 Sandwich Panel Strength

In Example 3, the flame retardancy was greatly increased by the increase of the flame retardant, and the mechanical strength was improved as the density was increased.

As described above, the present invention provides a foam composition and a method for producing the foam, which make it possible to obtain a foam having a specific specific gravity from low to high specific gravity, which can be used in various fields using sponge scrap and waste plastic (olefin-based). In particular, when the foam composition of the present invention is used as a sandwich panel, the flexural strength is higher than that of existing products (PU products and polystyrene products), so that the panel thickness can be made relatively thin and light, and the production cost can be reduced. It is an invention that can contribute to resource utilization.

Claims (3)

10 to 90 parts of sponge scrap (EVA, PP, PE) as waste material base resin, 10 to 80 parts of waste plastic, 0 to 10 parts of binder polymer are crushed and mixed in parts by weight, and as a member, 1 to 5 parts of plasticizer and crosslinking agent 0.1 A foam composition using sponge scrap and waste plastic, which is configured to be kneaded with 5 parts by weight and 1 to 15 parts of a foaming agent together with a base resin, molded into a sheet, and heated and pressurized in a press and depressurized. The foam according to claim 1, wherein 5 to 40 parts of a flame retardant selected from antimony trioxide, Al (OH) ₂ , Mg (OH) ₂ , CP wax, TCP, an incombustible flame retardant, a reactive flame retardant, and paraffin chloride are added to the member by weight part. Foam composition using a sponge scrap and waste plastic to impart flame retardancy. 10 to 90 parts of sponge scrap (EVA, PP, PE) as waste material base resin, 10 to 80 parts of waste plastic, 0 to 10 parts of binder polymer are crushed and mixed, and 1 to 5 parts of plasticizer and 0.1 to 5 crosslinking agent as a member. 1, 15 parts of the blowing agent and 4 to 40 parts of the flame retardant are kneaded together with the base resin by weight part, molded into a sheet form, heated and pressurized in a press, depressurized and foamed into a sheet to prepare a foam using waste plastic. Way.