Hydrofluoroethers having at least one hydrogenated-OCFX'CH3 end group wherein X'=F, CF3 and their preparation process

Hydrofluoroethers of formula:

• T—CFX′—O—Rf—CFX—T′ (II)
• wherein:
• T=CH3;
• X, X′, equal to or different from each other, are selected between F, CF3;
• T′=F, Cl, H, C1-C3 perfluoroalkyl, CH3, CH2OH, COCl, CHO, CO2H;
• Rf is selected from:
• C2-C15 perfluoroalkylene;
• —(C2F4O)m(CF2CF(CF3)O)n(CF2O)p(CF(CF3)O)q—
• wherein
• the sum n+m+p+q ranges from 2 to 200, the (p+q)/(m+n+p+q) ratio is lower than or equal to 10:100, preferably comprised between 0.5:100 and 4:100, the n/m ratio ranges from 0.2 to 6, preferably from 0.5 to 3;
• m, n, p, q are equal to or different from each other and when m, n range from 1 to 100, preferably from 1 to 80, then p, q range from 0 to 80, preferably from 0 to 50;
• the units with n, m, p, q indexes being statistically distributed along the chain;
• —(CF2CF2CF2O)r— wherein r ranges from 2 to 200,
• —(CF(CF3)CF2O)s— wherein s ranges from 2 to 200,