1. Enhances electric property and mechanical strength of EPDM filled with inorganic filler, cross-linked polyethylene and its polymer or resin. Its performance is especially more remarkable under the hygrometric state. Adding it by using the blend method, it can be used as the surface treating agent for the pottery clay and siliceous inorganic filler.   2. Enhances mechanical strength of composite materials such as cross-linked polyester, inorganic filler filled or reinforced polyester and so on under the hygrometric state. A-172 can reduce the water absorbability, electric property and mechanical strength of the cross-linked polyester mould pressing materials.