of the thermoplastic polymer system can be a single polymer or a blend alloy typically this thermoplastic polymer system will be chosen from the list of polymer systems such as polyethylene polypropylene polyether block polyamides polyester block co polymers styrenic block co polymers styrene based co and ter polymers such as abs hips asa sibs sebs sbs etc polyesters such as pet ptt petg pbt polycarbonates polyphylene sulfide polysulfones thermoplastic elastomers acrylate polymers specifically ethylene methacrylate thermoplastic urethanes and their blends alloys thereof additionally the polymer system may contain polymeric modifiers and other additives the dicarboxylic acid which can be used in the hard polyesters that are useful in the practice of this invention are typically selected from the group consisting of terephthalic acid isophthalic acid naphthalenedicarboxylic acid diphenyldicarboxylic acid or a mixture of 2 or more thereof the diol used for the polyester is typically an alkylene glycol that contains 2 10 carbon atoms 1 6 cyclohexanediol 1 6 dimethanolcyclohexane or a mixture of two or more thereof in general it is preferred that a polyester having a more crystalline structure be used these polyesters include poly butylenes terephthalate pbt poly ethylene terephthalate pet poly trimethylene terephthalate ptt poly butylenes isophthalate pbi poly cyclohexylene dimethylene terephthalate pct.