4 phenylene ether poly 2 6 diethyl 1 4 phenylene ether or mixtures thereof with polystyrene these polyphenyleneethers preferably have a degree of polymerization in the range of 20 to 800 a polyarylate to be used in the present composition has a polymeric chain represented by the general formula of str4 and preferable has a degree of polymerization of 10 to 1 000 a thermoplastic polysulfone can also be used in the present composition and has at least some units represented by the general formula of str5 wherein z is oxygen sulfur or an aromatic diol residue such units can be exemplified by any of the following repeating units str6 the halogen containing thermoplastic resins which can be used in the present composition include tetrafluoroethylene polymer chlorotrifluoroethylene polymer and vinylidene fluoride polymer a homopolymer or copolymer derived from vinylidene chloride can also be used in the present composition preferred halogen containing thermoplastic resins are a homopolymer or copolymer of vinylidene fluoride as well as crystalline vinylidene chloride copolymer the nitrile resins to be used in the present composition are those containing 50 by weight or more of an u03b1 u03b2 olefinic unsaturated mononitrile the u03b1 u03b2 olefinic unsaturated mononitrile has a structural formula of str7 wherein r is hydrogen an alkyl group having 1 to 4 carbon atoms or a halogen the most preferable olefinic unsaturated nitriles are acrylonitrile methacrylonitrile and mixtures thereof the above mentioned engineering thermoplastic resins can be used alone or in combination the resins can be introduced with sulfonic acid group amino group nitro group a halogen group etc or copolymerized with an unsaturated organic acid or an acid anhydride as necessary to satisfactorily cover the ends of fibrous or lamellate.