公开(公告)号：AU631737B2

公开(公告)日：1992-12-03

申请号：AU7521491

申请日：1991-04-22

Applicant: ATOCHEM NORTH AMERICA, INC.

Inventor： LEONARD ALOYSIUS BARBER

IPC: C08F2/00 ,  C08F2/22 ,  C08F14/22 ,  C08F14/28 ,  C08F214/22 ,  C08F214/28 ,  C08F259/08

Abstract: Melt processable copolymers of vinylidene fluoride and hexafluoropropylene, containing from about 1% to about 20% hexafluoropropylene by weight, are prepared by emulsion polymerization of vinylidene fluoride and hexafluoropropylene in a stirred aqueous reaction medium. The reaction medium is formed by charging to a heated reactor, water, vinylidene fluoride, an initiator to start the polymerization, and a water-soluble surfactant capable of emulsifying both the initiator and the reaction mass during polymerization. Additional amounts of vinylidene fluoride and initiator are fed to the reaction medium to continue polymerization of the vinylidene fluoride monomer until from abut 50% to abut 90% of the total weight of the vinylidene fluoride monomer utilized in the process has been added to the reaction medium. There is then added to the reaction medium (i) from about 1% to about 20% hexafluoropropylene by weight, based upon the combined weight of the hexafluoropropylene and the total weight of the vinylidene fluoride utilized in the process, and (ii) the balance of the vinylidene fluoride utilized in the process. The resulting vinylidene fluoride/hexafluoropropylene copolymers are characterized by improved mechanical properties and a DSC melting point typically in the range of from about 160 DEG C to about 170 DEG C, preferably from about 163 DEG C to about 168 DEG C.