| 摘要 |
Thermoplastic materials of the vinyl polymer type, such as polyvinyl chloride, polyvinylidene chloride, or vinyl chloride-vinyl chloride copolymers, are rendered porous by incorporating therein as a gas generating agent the reaction products obtained by condensing hydrazine hydrate with benzil, such as benzoyl phenyl hydrazi methylene, and heating the resulting product to liberate nitrogen, a residue of benzyl phenyl ketone remaining. The process may be carried out by homogenizing the resinous material with aluminium stearate, tricresyl phosphate, and the gas generating agent, followed by heating the composition to above 160 DEG C. Before heating, the compositions may be applied to a textile fabric to provide, after heating, a fabric coated with a layer of porous material. |
