Abstract: The subject is to provide a polymer material which enables to improve planarity and planarization efficiency of a polished surface and is useful as a polishing pad which generates only a few scratches. The said subject is solved by a polymer material having a tensile modulus at 50° C. after saturation swelling with 50° C. water of 130 to 800 MPa, a loss tangent at 50° C. of not more than 0.2, and a contact angle with water of not more than 80°.

Abstract: The subject is to provide a polymer material which enables to improve planarity and planarization efficiency of a polished surface and is useful as a polishing pad which generates only a few scratches. The said subject is solved by a polymer material having a tensile modulus at 50° C. after saturation swelling with 50° C. water of 130 to 800 MPa, a loss tangent at 50° C. of not more than 0.2, and a contact angle with water of not more than 80°.

Abstract: The present invention aims to provide a polyurethane foam, suitably usable as a polishing pad, having a uniform foam structure, which can achieve the improvements in the flatness of the surface of polished materials and in the planarization efficiency, and can extend the polishing pad life longer than that of the conventional polyurethane foams. This aim can be achieved by providing a polyurethane foam having a density of 0.5 to 1.0 g/cm3, a cell size of 5 to 200 ?m and a hardness [JIS-C hardness] of not less than 90, comprising a thermoplastic polyurethane which is obtained by a reaction of a high polymer polyol, an organic diisocyanate and a chain extender, contains not less than 6% by weight of a nitrogen atom derived from the isocyanate group, and has a storage elastic modulus measured at 50° C. [E?50] of not less than 5×109 dyn/cm2.

Abstract: The present invention aims to provide a polyurethane foam, suitably usable as a polishing pad, having a uniform foam structure, which can achieve the improvements in the flatness of the surface of polished materials and in the planarization efficiency, and can extend the polishing pad life longer than that of the conventional polyurethane foams. This aim can be achieved by providing a polyurethane foam having a density of 0.5 to 1.0 g/cm3, a cell size of 5 to 200 &mgr;m and a hardness [JIS-C hardness] of not less than 90, comprising a thermoplastic polyurethane which is obtained by a reaction of a high polymer polyol, an organic diisocyanate and a chain extender, contains not less than 6% by weight of a nitrogen atom derived from the isocyanate group, and has a storage elastic modulus measured at 50° C. [E′50] of not less than 5×109 dyn/cm2.

Abstract: Incorporation in a thermoplastic resin of a mass of mica flakes having a median shape factor of not less than 0.76, an average particle size of not more than 2,000 .mu.m and an average aspect ratio of not less than 10 followed by molding gives moldings which are high not only in mechanical strength but also in strength at weld parts. Incorporation of said mica flake mass in a thermosetting resin followed by molding affords moldings very high in strength as well as in modulus of elasticity.