PROCESS FOR THE STABILIZATION OF FLUOROPOLYMERS

摘要

Melt-processible copolymers of at least two halogenated comonomers from a defined class, especially perhalogenated comonomers, and particularly perfluorinated comonomers, of improved thermal stability are obtained by first contacting the copolymers with a stabilizing agent selected from bases (ammonia or amines) having a boiling point at normal pressure of at most 130 DEG C and tertiary alcohols having up to 8 carbon atoms, to form an intermediate, drying the intermediate at about 70-150 DEG C, and fluorinating the intermediate at a temperature between 20 DEG C and the lowest temperature at which the copolymer exhibits a solid state transition, then removing excess fluorine and by-products and recovering the stabilized copolymer. Such stabilized copolymers are useful for a variety of technically important applications, including as cladding for optical fibers, substrates for electronic components, thermal laminates, pipes, tubes, and fittings, etc.