Polymer composition for powder molding, powder thereof, foamed articles, and method for producing foamed article

Abstract

A polymer composition for powder molding, containing (A) to (E) described below: (A) a peroxide-crosslinkable olefin-based copolymer having a melt flow rate measured under the conditions of a load of 2.16 kgf and a temperature of 190° C. according to JIS K7210 of 1 g/10 min. or more; (B) 0.1 to 10 parts by weight of a peroxide having a temperature for obtaining a half life of 10 hours of 100° C. or more, per 100 parts by weight of (A); (C) 0.1 to 7 parts by weight of a crosslinking aid per 100 parts by weight of (A); (D) 0.1 to 20 parts by weight of a thermal decomposition type foaming agent per 100 parts by weight of (A); and (E) 0.1 to 10 parts by weight of a foaming aid per 100 parts by weight of (A), a powder and foamed article of the polymer composition, a method for producing the foamed article, and a molded article containing the foamed article, and further the polymer composition is excellent in the storage stability of its uncrosslinked composition, and can provide a foamed article having a high expansion ratio and an excellent surface skin, and hardly having a skin lack of hiding.

1 . A polymer composition for powder molding, containing (A) to (E) described below: 
 (A) a peroxide-crosslinkable olefin-based copolymer having a melt flow rate measured under the conditions of a load of 2.16 kgf and a temperature of 190° C. according to JIS K7210 of 1 g/10 min. or more;    (B) 0.1 to 10 parts by weight of a peroxide having a temperature for obtaining a half life of 10 hours of 100° C. or more, per 100 parts by weight of (A);    (C) 0.1 to 7 parts by weight of a crosslinking aid per 100 parts by weight of (A);    (D) 0.1 to 20 parts by weight of a thermal decomposition type foaming agent per 100 parts by weight of (A); and    (E) 0.1 to 10 parts by weight of a foaming aid per 100 parts by weight of (A).    
     
     
         2 . A powder composed of the polymer composition according to  claim 1 .  
     
     
         3 . The powder according to  claim 2 , wherein a sphere-reduced average particle diameter is 50 to 1200 μm.  
     
     
         4 . A foamed article obtained by crosslinking-foaming the powder of  claim 2 .  
     
     
         5 . A foamed article obtained by crosslinking-foaming the powder of  claim 2  according to slush molding.  
     
     
         6 . A method for producing a foamed article, which comprises crosslinking-foaming the powder of  claim 2 .  
     
     
         7 . A method for producing a foamed article, which comprises crosslinking-foaming the powder of  claim 2  according to slush molding.  
     
     
         8 . A two-layer molded article prepared by laminating a non-foamed layer composed of a thermoplastic polymer composition or a vinyl chloride-based resin composition on a foamed layer composed of the foamed article of  claim 4 .  
     
     
         9 . A multi-layer molded article prepared by laminating a reinforcing layer composed of a thermoplastic resin composition or a thermoplastic elastomer composition on the foamed layer side of the two-layer molded article of  claim 8 .  
     
     
         10 . A multi-layer molded article prepared by laminating a base material layer composed of a thermoplastic resin composition or a thermoplastic elastomer composition on the foamed layer side of the two-layer molded article of  claim 8 .  
     
     
         11 . A multi-layer molded article prepared by laminating a base material layer composed of a thermoplastic resin composition or a thermoplastic elastomer composition on the reinforcing layer side of the multi-layer molded article of  claim 9.