JPS6280035A - Composite molded body - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The composite molded product of the present invention can be used as lining insulation material for refrigerator bodies and doors, door materials for show window cases and unit baths that require heat insulation, It is useful for automobile interior materials such as automobile bumpers and door trims that require cushioning properties, and for surfing boats. Acrylonitrile-butadiene-styrene copolymer (commonly known as rABsJ) sheets, which are styrenic resins, are vacuum-formed, pressure-formed, or formed using a combination of vacuum and pressure-air (hereinafter referred to as The lining material is obtained by molding (collectively referred to as thermoforming) or injection molding. In addition, ABS made in-house lumber has excellent surface gloss, low water absorption, and
The use of polypropylene lining material, which is economically advantageous, has been proposed.

In order to improve the heat insulation properties of these lining materials, it has been proposed to interpose foamed polyurethane between the structural base material and the lining material (C JP-A No. 60-97841).

In addition, door materials for unit baths are currently made of polyvinyl chloride sheets, but when used at high temperatures,
There is a problem in which the sash frame is corroded by the chlorine gas generated by decomposition, so in order to improve this problem, two polypropylene sheets are attached to the aluminum sash frame instead of using a polyvinyl chloride sheet, and the aluminum sash frame and sheet are used to surround it. Consideration is being given to filling the empty space with polyurethane foam to give it more rigidity as a door.

Furthermore, with the transition from metal to resin for interior materials such as automobile door trims, filling polyurethane foam by injection method is being considered for the purpose of cushioning or heat insulation.

As described above, there is a demand for composites of sugar beet materials and foamed polyurethane in resin products having various complex shapes.

[Problem that the invention seeks to solve]

However, the resin material is usually a sheet or a molded sheet by thermoforming or injection molding, and when polyolefin resin in such a shape is used, the adhesive strength with polyurethane foam is insufficient. Therefore, voids are formed, which has the disadvantage that the purpose of rigidity and heat insulation cannot be fully achieved.

In order to improve the adhesive strength between this resin material and foamed polyurethane, it is possible to apply a liquid adhesive or adhesive liquid or to treat the surface with chemicals (@Kaisei No. 60-97841), but the number of coating and surface treatment steps increases. The addition of complicated steps is not desirable. Further, the adhesive resin layer that adheres to the urethane foam needs to be resistant to corrosion by Freon gas mixed into the urethane.

The present invention eliminates such a treatment step and improves the adhesive strength with urethane foam by blending a styrene-based tIt resin such as ABS with an olefin resin that adheres to urethane foam and is not easily corroded by Freon gas.

[Structure of the invention]

The present invention provides a composite molded article having a structure in which urethane foam and the following resin layers are laminated together. A) Component olefin resins include non-polar olefin resins such as polyethylene, polypropylene, ethylene/propylene copolymer, ethylene/propylene/butene copolymer, ethylene/acrylic acid random copolymer, ethylene/methacrylic acid, etc. Random copolymer, acrylic acid kraft polyethylene, methacrylic acid kraft polyethylene, maleic anhydride kraft polyethylene, maleic anhydride grafted polypropylene,
Carboxyl group-containing olefin resins such as maleic anhydride grafted ethylene/vinyl acetate copolymer and itaconic acid kraft polyethylene can be used, and these can be used alone or as a mixture. Among these, propylene/ethylene block copolymers with an ethylene content of 2 to 12% by weight or polypropylene of 50 to 90% by weight are particularly suitable! 4
And polyethylene 50-10 weight! A mixture of 4 is preferred.

This olefin resin may be blended with a resin such as an ethylene/vinyl acetate copolymer, a stabilizer, a rubber, a pigment, or an inorganic filler.
ABS, SBS, SA, HIP8, etc. can be used. Among these, ABS has higher adhesion between the urethane foam and the adhesive layer.

The adhesive layer is melt-kneaded using an extruder, fed to an extrusion die, extruded into a sheet or parison, and then vacuum-formed, compression-molded, or blow-molded to be used as refrigerator lining material or for surfboards. Sareki.

Molded objects such as bumpers are manufactured by injection molding.

The wall thickness of the molded body is 0.5 to 15 m, preferably tIiz to
5I, and the surfaces of these molded bodies may be subjected to corona discharge treatment, flame treatment, or plasma treatment if necessary.

(?J! Composite molded body) A composite molded body is one in which a urethane foam and a resin layer are bonded together.

In the case of a surfing board, a foaming urethane liquid is injected into the hollow part of the hollow-molded molded body and the surfboard is foamed.

When used as interior material for a refrigerator, as shown in Fig. 1, a formwork (1) made of decorative steel plate and the vacuum-formed laminate (2) are used.
A foamable urethane solution (4) is injected into the cavity (3) formed by the foaming urethane solution (4), and then foamed and hardened to form the mold (
A multi-layered structure in which 1), urethane foam (4), and lining material (2) are integrated is manufactured.

Hereinafter, the present invention will be explained in more detail with reference to Examples. Note that parts and parts in the examples are based on weight.

Sheet manufacturing example Example 1 Resin to be adhered to urethane foam: ethylene content 5 parts by weight, MFRo, sf 710 minutes, boiling hebutane extraction residue 98 parts by weight crystalline propylene-ethylene block copolymer 50 parts by weight, AB8 manufactured by Mitsubishi Monsando Chemicals
A mixture of "Tufflex 157" (trade name) (trade name) 50 weight grams was kneaded using an extruder, extruded into strands, and cut into pellets.

Using an extruder with a diameter of 90+mg, the above pellet was
The mixture was melt-kneaded at 0°C and supplied to a manifold die with a width of 700 m. The molten flat sheet extruded from the die was sequentially cooled and solidified using three rolls each having a width of 800 m to obtain a sheet. The temperature of the roll is 80℃, 9 from the roll to the die.
5℃, 100℃, and the rotation speed of the roll is 1.5
m/min. The sheet thickness was 1.5 mm.

A sheet was obtained in the same manner.

The abbreviations in the table are as follows.

PP: Propylene/ethylene block copolymer (contains ethylene! 5-layer width) Tuflex 157: ABS made by Mitsubishi Monsanto Kasei Taflex 461: ABC made by Mitsubishi Monsanto Kasei (
Product name) PS: Styrene HH102: Polystyrene 1 Dialex HL-1102' manufactured by Mitsubishi Monsanto Kasei ■ (Product name) i-IT 516, Polystyrene 1 Dialex HT516'' manufactured by Mitsubishi Monsanto Chemical ■ (Product name) Toughbrain N: Asahi Kasei ■ Example of the product name of 8BS made by Manufacturer! The sheet obtained in Example 1 was molded using a combination vacuum and air pressure molding machine.
It was introduced into a heating furnace set at about 230°C and heated with IE air (5, O
Kg/cyl) and reduced pressure (-a o (1+mHIZ
) was used in combination with plug assist molding (drawing ratio H/
D=1/2). The release properties of the sheet were good, and the plug was easily separated from the sheet.

After drilling an injection port in a part of this shaped sheet, this sheet is inserted into a stainless steel frame that is the frame of the refrigerator body, and then the space formed by the frame and the shaped sheet is (Polyurethane Kagaku Kasei@Agricultural 2-component foaming polyurethane solution i1HM-1510 is poured into the cavity from the injection port.
When 1 (trade name) was injected, foaming started 10 seconds later, and the space was completely filled with urethane foam 1 minute later. The density of this urethane foam is α05f
/cd. The same operation was repeated 20 times to obtain 20 composite molded body samples.

After 24 hours, the sheet with the urethane foam adhered to it was cut out, and the adhesion between the urethane foam and the sheet was measured by the following method.

After manually separating the urethane foam from the sample piece, the remaining 7-ohm urethane sheet was pierced with a knife for 10 ohms.
After cutting 0 1st gourd squares, adhesive tape was applied onto the squares, and when the adhesive tape was carefully pulled away from the sheet, the squares of urethane foam remaining on the sheet side were examined.

The results are shown in Table 1.

The evaluation criteria are as follows.

d゛A state in which urethane foam cohesive failure and interfacial peeling with the urethane foam coexist on the peeling surface.

It is weak and the sheet easily peels off from the interface with the urethane foam.

(-~-!!-) Examples 2 to 8, Comparative Examples 1 to 4 Composite molded bodies were obtained in the same manner except that the soaked layer sheets were replaced with those of Examples 2 to 12 instead of those of Example 1. .

Table 1 shows the adhesion between the urethane foam and the sheet of these composite molded bodies.

(Leaving space below) Example 9 One piece of a mixture of the propylene/ethylene block copolymer 50 weight 81 used in Example 1 and AB8 "Tufflex 157" 50 weight was bound and molded using an 800 ton injection molding machine. A molded body for a bumper was obtained by injection molding into a mold at a temperature of 70°C at a temperature of about 230°C and an injection pressure of 100 to 9/-.

This molded body was surrounded by a frame, and a two-component urethane liquid was injected into the frame and foamed to obtain a bumper for an automobile. The adhesion between the urethane foam and the molded article was stronger than that of Example 1.

[BRIEF DESCRIPTION OF THE DRAWINGS] The figure is a sectional view showing one embodiment of the present invention, in which 1 is a stainless steel frame, 2 is a resin sheet, 3 is a cavity,
4 is a urethane foam, and 5 is an injection port.

Claims (1)

[Claims] 1) A composite molded resin composition having a structure in which urethane foam and the following resin layers are integrally laminated A) Olefin resin 50 to 80% by weight B) Styrene resin 50 to 20% by weight weight%. 2) The olefin resin has an ethylene content of 2 to 12% by weight.
The composite molded article according to claim 1, which is a propylene/ethylene block copolymer. 3) The composite molded article according to claim 1, wherein the olefin resin is a mixture of polypropylene and polyethylene, and the blending ratio is 50 to 90% by weight of polypropylene and 50 to 10% by weight of polyethylene. 4) The composite molded article according to claim 1, wherein the styrene resin is an acrylonitrile-butadiene-styrene copolymer.