Low viscosity fluoroelastomers

摘要

The invention pertains to a low viscosity curable (per)fluoroelastomer [fluoroelastomer (A)] having a number-averaged molecular weight of 3 000 to 45 000, said (per)fluoroelastomer comprising at least 1% moles, with respect to the total moles of recurring units, of recurring units derived from at least one (per)fluoromethoxyalkylvinylether of formula (I):
CFX′═CX″OCF2ORf  formula (I)
wherein X′ and X″, equal to or different from each other, are independently H or F; and Rf is selected from the group consisting of C1-C6 (per)fluoroalkyls, linear or branched; C5-C6 cyclic (per)fluoroalkyls; and C2-C6 (per)fluorooxyalkyls, linear or branched, comprising from 1 to 3 catenary ethereal oxygen atoms [monomer (M)].

主权项

1. A low viscosity curable fluoroelastomer or (per)fluoroelastomer [fluoroelastomer (A)] having a number-averaged molecular weight of 3,000 to 45,000, said fluoroelastomer (A) comprising:
at least 1% moles, with respect to the total moles of recurring units, of recurring units derived from at least one (per)fluoromethoxyalkylvinylether of formula (I):
CFX′═CX″OCF2ORf  formula (I)wherein X′ and X″, equal to or different from each other, are independently H or F; and Rf is selected from the group consisting of C1-C6 (per)fluoroalkyls, linear or branched; C5-C6 cyclic (per)fluoroalkyls; and C2-C6 (per)fluorooxyalkyls, linear or branched, comprising from 1 to 3 catenary ethereal oxygen atoms [monomer (M)],
recurring units derived from vinylidene fluoride (VDF), from tetrafluoroethylene (TFE), or from a combination thereof, and optionally recurring units derived from at least one additional (per)fluorinated monomer [comonomer (C)], wherein comonomer (C) is different from monomer (M), VDF and TFE.