| 摘要 |
<p>Compounds usable as stabilizing additives of perfluoropolyether fluids working at high temperatures, higher than 200°C, and/or in the presence of metals and/or in the presence of Lewis acids, are formed of (per)fluoropolyether chains and of end groups having a heteroaromatic structure, according to the following general formula:
€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ T 1 -CFW 1 -O-R f -CFW 2 -T 2 €ƒ€ƒ€ƒ€ƒ€ƒ(I)
wherein T 1 , T 2 , equal to or different from each other, have the following meanings: F, CF 3 , C 2 F 5 , (C 2 F 4 )Cl -CH 2 -B-Y, -CH(CF 3 )O-Y, wherein: B = O, S; Y is a substituent formed of a ring having a heterocyclic structure having the following formula:
wherein: R 1 , R 2 , R 3 , R 4 , equal to or different from each other are H, linear or branched C 1 -C 8 perfluoroalkyl, NO 2 , CN, preferably H;
with the proviso that at least one of the two end groups T 1 , T 2 is -CH 2 -B-Y or -CH(CF 3 )O-Y, wherein B and Y are as above; W 1 , W 2 , equal to or different from each other, are -F, -CF 3 ;
Rf is a (per)fluoropolyoxyalkylene chain having a number average molecular weight between 500 and 10,000, preferably between 800 and 5,000.</p> |
