Fluorine-containing compounds having polyacetalic structure, and process for preparing them

摘要

1) Disclosed herein are new fluorine-containing compounds having polyacetalic structure, of general formula:[Rfm-CH2O(CH2O)c-CH2-+548 n(I)where: Rf=a perfluorooxyalkylene chain having +E,ovs M+EE n from 500 to 5,000; m=4-25; c=1-10; n=2-100. 2) A process for preparing them which comprises carrying out the polycondensation of diols having formula:HORfOH(II)with formaldehyde, in mass or in the presence of solvents, in an acid medium. The compounds of formula (I) can be oligomeric compounds (polymerization degree +E,ovs x+EE n from 2 to about 20) or polymeric compounds (+E,ovs x+EE n from about 20 to about 100). They exhibit a high stability to heat and to chemical agents, and Tg values slightly different from the ones of the diols utilized for preparing them.