Polycarbonate resin composition

Abstract

The present invention aims at modifying a polyblend mainly comprising a polycarbonate resin and a polystyrene resin into a thermoplastic resin composition having flowability and impact strength equivalent to those of a polyblend comprising a polycarbonate resin and an ABS resin, and at providing a harmless flame-retardant thermoplastic resin composition based on the resulting modified composition. Specifically, the present invention relates to a thermoplastic resin comprising 100 parts by weight of a resin mixture comprising 30 to 95% by weight of a polycarbonate resin (a), 5 to 70% by weight of a polystyrene resin (b), 0.5 to 20 parts by weight of a specific block copolymer (c) and, if necessary, 0.1 to 20 parts by weight of a polyalkylene terephthalate (d), and/or 0.1 to 20 parts by weight of a polyphenylene ether resin (e), and a flame-retardant thermoplastic resin composition prepared by blending the above composition with 1 to 40 parts by weight of an organophosphorus compound (f) and, if necessary, 0.05 to 5 parts by weight of a fluoroethylene polymer (g).

1 . A thermoplastic resin composition comprising 100 parts by weight of a resin mixture comprising 30 to 95% by weight of a polycarbonate resin (a) and 5 to 70% by weight of a polystyrene resin (b), and 0.5 to 20 parts by weight of at least one member (c) selected from the group consisting of (I) block copolymers (C), wherein both a polymeric block (A) mainly made from an aromatic vinyl compound and a polymeric block (B) mainly made from a conjugated diene compound are present in each molecule, and/or partially hydrogenated derivatives thereof (D), (II) epoxidized block copolymers (E) derived from the block copolymers (C) and/or the partially hydrogenated derivatives (D), epoxidized through the epoxidation of double bonds resulting from the conjugated diene compound, and (III) acid-modified block copolymers (F) derived from the block copolymers (C) and/or the partially hydrogentated derivatives (D).  
     
     
         2 . The thermoplastic resin composition as claimed in  claim 1 , wherein the component (b) is a rubber-modified polystyrene resin satisfying the following requirements 1) to 3): 
 1) the content of rubbery polymer in the rubber-modified polystyrene resin is 15 to 25% by weight,    2) the volume mean particle diameter of rubbery polymer contained in the rubber-modified polystyrene resin is 0.3 to 5.0 μm, and    3) the gel content of the rubber-modified polystyrene resin is 15 to 70% by weight.    
     
     
         3 . The thermoplastic resin composition as claimed in  claim 1 , wherein the component (c) is one or more of the epoxidized block copolymers (II).  
     
     
         4 . The thermoplastic resin composition as claimed in  claim 1 , which further contains 0.1 to 20 parts by weight of a polyalykylene terephthalate (d).  
     
     
         5 . The thermoplastic resin composition as claimed in  claim 1 , which further contains 0.1 to 20 parts by weight of a polyphenylene ether resin (e).  
     
     
         6 . The thermoplastic resin composition as claimed in  claim 1 , which further contains 1 to 40 parts by weight of (f) an organophosphorus compound.  
     
     
         7 . The thermoplastic resin composition as claimed in  claim 1 , which further contains 0.05 to 5 parts by weight of a fluoroethylene polymer (g).  
     
     
         8 . A thermoplastic resin composition comprising 100 parts by weight of a resin mixture comprising 10 to 94.9% by weight of the component (a), 5 to 70% by weight of the component (b) and 0.1 to 20% by weight of an aromatic polyester (h) and 0.5 to 20 parts by weight of (II) as defined in  claim 1 .  
     
     
         9 . The thermoplastic resin composition as claimed in  claim 8 , which further contains 1 to 150 parts by weight of (i) a flame retardant.  
     
     
         10 . The thermoplastic resin composition as claimed in  claim 8 , which further contains 1 to 40 parts by weight of (f) an organophosphorus compound.  
     
     
         11 . The thermoplastic resin composition as claimed in  claim 8 , which further contains 0.05 to 5 parts by weight of a fluoroethylene polymer (g).