The present invention relates to a monomeric composition and a polymer obtained by the polymerization thereof or, more particularly, to a monomeric composition capable of being polymerized into a curable polymer which gives a rubbery elastomer having excellent heat and cold resistance and oil resistance as well as a polymer obtained from the monomeric composition.
So-called acrylic rubbers belong to a class of synthetic rubbers obtained by the copolymerization of an acrylic monomer such as ethyl acrylate, n-butyl acrylate, 2-methoxyethyl acrylate, 2-ethoxyethyl acrylate and the like with a comonomer which gives crosslinking points in the molecules of the copolymer. Acrylic rubbers obtained from ethyl acrylate as the principal comonomer have excellent oil resistance and heat resistance but the cold resistance thereof is poor. Acrylic rubbers obtained from n-butyl acrylate as the principal comonomer have excellent heat and cold resistance but the oil resistance thereof is poor. Further, acrylic rubbers obtained from 2-methoxyethyl or 2-ethoxyethyl acrylate as the principal comonomer have excellent cold resistance and oil resistance but they have rather poor heat resistance. Thus, none of the conventional acrylic rubbers satisfies the requirements for the oil resistance and cold resistance simultaneously.