METHOD OF SELECTIVELY MODIFYING INNER PROPERTIES OF POLYMER STRUCTURE

摘要

A method for selectively hardening and toughening the bulk mass of predetermined portions of a polymeric structure which includes the steps of contacting the polymeric structure with a multifunctional monomer to diffuse the monomer into the polymeric structure and irradiating the predetermined portions of the polymeric structure with activating radiation to cause the bulk polymeric material at those portions to be hardened and toughened. In a preferred embodiment the character fonts of a print wheel made from nylon 66 are contacted with a multifunctional monomer which is subsequently exposed to electron beam radiation whereby a structural network of monomer or monomer reactive with polymer or mixtures is formed.