Abstract:
Use for improving the hydro- and oil-repellence properties of substrata having a low surface energy of (per)fluoropolyether mono- and bifunctional derivatives having the structures:WnullLnullYFCnullOnullRfnullCFYnullLnullWnullnull(I)RfnullCFYnullLnullWnullnull(II)wherein: L is a linking organic group nullCOnullNRnullnull(CH2)qnull, with RnullnullH or C1-C4 alkyl; q is comprised between 1 and 8; YnullF, CF3; W is a nullSi(R1)null(OR2)3-null group with nullnull0,1,2, R1 and R2 equal to or different from each other are C1-C6 alkyl groups, C6-C10 aryl groups, C7-C12 alkyl-aryls or aryl-alkyls; Rf has a number average molecular weight in the range 200-5,000 and comprises repeating units having at least one of the following structures:(CFXO), (CF2CF2O), (CF(CF3)CF2O), (CF2CF(CF3)O),wherein XnullF, CF3.
Abstract:
Perfluoropolyethers having structural formulaR1Onull(CF2O)nnull(CF2CF2O)mR2nullnull(I)wherein: R1 is nullCH3 or nullC2H5; R2 is equal to R1 or nullCF2H n is 0 or an integer from 1 to 100; m is an integer from 1 to 100 or, when R2 is nullCF2H, m can also be 0; the oxyfluoro-alkylene units null(CF2CF2O)null and null(CF2O)null are statistically distributed along the polymer chain.
Abstract:
Mixtures of fluoropolymer dispersion, wherein: a) a dispersion is formed by TFE (co)polymers with average particle sizes in the range 180-400 nm; b) another dispersion selected from: 1) (co)polymer dispersion of TFE; 2) thermoplastic copolymers of TFE; the average particle sizes of dispersion b) range from 20 to 60 nm; the ratio between the particle sizes of dispersion b) compared with those of dispersion a) is lower than 0.3.
Abstract:
Method for removing water from surfaces of various materials, comprising the steps of covering said surface with a composition having specific weight higher than that of water and subsequently removing water from the composition by skimming, wherein a composition essentially consisting of the following components is used: a fluorinated non ionic additive component A) of formula: T-ORf(CFY)-L nullnull(I) a (per)fluoropolyether component B), wherein the ratio by weight (K) between the (per)fluorinated part and the hydrogenated L part of the additive is in the range 1.50-4.00 and the ratio KI between the number average molecular weight of the fluoropolyether part T-ORf- of the additive and the number average molecular weight of the component B) is higher than 1.60.