Fluorinated polymers containing perfluoropolyoxyalkylene sequences and having thermoplastic elastomeric properties

Fluorinated polymers having thermoplastic elastomeric properties, comprising perfluoropolyoxyalkylene sequences having the formula:

• --CF.sub.2 O--(CF.sub.2 CF.sub.2 O).sub.m --(CF.sub.2 O).sub.n --CF.sub.2 --(I)
• wherein
• (i) the ratio m/n is from 0.2 to 5, and
• (ii) the number average molecular weight of the perfluoropolyoxyalkylene sequences is from 500 to 10,000;
• the perfluoropolyoxyalkylene sequences being linked to each other by organic groups derived from one or more condensation monomers having a functionality equal to 2;
• the fluorinated polymers having a number average molecular weight at least 50% higher than that of the corresponding polymers obtained by polycondensation of perfluoropolyoxyalkylenes with sequences corresponding to formula (I) and having a functionality equal to or lower than 1.96;
• wherein the fluorinated polymers are obtained by reacting the condensation monomers with perfluoropolyoxyalkylene starting materials having the formula:
• Z--CF.sub.2 O--(CF.sub.2 CF.sub.2 O).sub.m --(CF.sub.2 O).sub.n --CF.sub.2 --Z (VI)
• wherein
• (a) the ratio m/n is from 0.2 to 5 and each Z is a reactive group which will react in a polycondensation reaction with the condensation monomers;
• (b) the perfluoropolyoxyalkylene starting materials have a functionality equal to at least 1.97 and a number average molecular weight for the perfluoropolyoxyalkylene sequences between the Z groups of from 500 to 10,000.