摘要:
The invention relates to (per)fluoropolyether block copolymers comprising: A) a fluoropolyoxyalkylene segment (chain Ra) comprising one or more units of formula (CHXCF2CF2O)— in which X is hydrogen or fluorine; B) a (per)fluoropolyoxyalkylene segment (chain Rf), that is to say a segment comprising recurring units having at least one catenary ether bond and at least one fluorocarbon moiety, said (per)fluoropolyoxyalkylene segment being different from chain Ra and having a molecular weight higher than 400 g/mol. These copolymers are endowed with improves lubricant properties or with improved water and oil-repellence properties.
摘要:
The invention relates to (per)fluoropolyether block copolymers comprising: A) a fluoropolyoxyalkylene segment (chain Ra) comprising one or more units of formula (CHXCF2CF2O)— in which X is hydrogen or fluorine; B) a (per)fluoropolyoxyalkylene segment (chain Rf), that is to say a segment comprising recurring units having at least one catenary ether bond and at least one fluorocarbon moiety, said (per)fluoropolyoxyalkylene segment being different from chain Ra and having a molecular weight higher than 400 g/mol. These copolymers are endowed with improves lubricant properties or with improved water and oil-repellence properties.
摘要:
An inner salt of L-carnitine is prepared by reduction, with a suitable reducing agent, of a compound of formula (I): 1 where X1 and X2, which may be the same or different, are hydroxy, C1-C4 alkoxy, phenoxy, halogen, or X1 and X2, when taken together are an oxygen atom and the resulting compound is a derivative of succinic anhydride; Y is halogen, a mesyloxy or a tosyloxy group, and subsequent treatment with water, then with a base and then with trimethylamine.
摘要:
Halofluorinated alkylene monomers are made by a method comprising the steps of: (a) subjecting a first polymer which is the reaction product of a fluorinated vinyl monomer and a vinyl comonomer to dehydrohalogenation to form a second polymer; (b) treating the second polymer with an oxidizing agent to form an oxidation product consisting of a .alpha., .omega.-dicarboxylic acid or an ester derivative thereof; and (c) treating said oxidation product with a reducing agent to form a reduction product consisting of a a .alpha., .omega.-diol. Preferably, the first polymer has a structure of --[CH.sub.2 CYZ(CF.sub.2 CFX).sub.n ].sub.m -- wherein X and Y=F, Cl or Br; X and Y may be the same or different; Z=H, F, Cl, Br, alkyl or perfluoroalkyl containing from about 1 to about 10 carbon atoms; n=an integer larger than about 1; and m is an integer between about 2 and about 10.sup.5. The .alpha., .omega.-dicarboxylic acids and .alpha., .omega.-diols produced herein can be directly used as polycondensation monomers. Alternatively, the .alpha., .omega.-dicarboxylic acids and .alpha., .omega.-diols can be further derivitized to tri-, tetra- or other multifunctional alcohols which may be directly used as condensation monomers or they may be converted to acrylates which may be photocured in the presence of a radical photoinitiator into transparent polymers which are useful as optical waveguiding materials.
摘要翻译:通过包括以下步骤的方法制备卤代亚烷基单体:(a)使作为氟化乙烯基单体和乙烯基共聚单体的反应产物的第一聚合物进行脱卤化氢以形成第二聚合物; (b)用氧化剂处理第二聚合物以形成由α,ω-二羧酸或其酯衍生物组成的氧化产物; 和(c)用还原剂处理所述氧化产物以形成由α,ω-二醇组成的还原产物。 优选地,第一聚合物具有 - [CH 2 CYZ(CF 2 CFX)n] m - 的结构,其中X和Y = F,Cl或Br; X和Y可以相同或不同; Z = H,F,Cl,Br,含有约1至约10个碳原子的烷基或全氟烷基; n =大于1的整数; m为约2至约105的整数。本文生产的α,ω-二羧酸和α,ω-二醇可直接用作缩聚单体。 或者,可以将α,ω-二羧酸和α,ω-二醇进一步衍生为可以直接用作缩合单体的三元,四元或其它多官能醇,或者它们可以转化成丙烯酸酯,其可以在 将自由基光引发剂存在于用作光波导材料的透明聚合物中。
摘要:
The present invention relates to an optically active .alpha.-substituted carboxylic acid derivative represented by the general formula (I): ##STR1## (wherein R.sub.1 is a hydroxyl group, ##STR2## R.sub.2 is a methyl group or a chlorine atom; R.sub.3 is a hydrogen atom or an alkyl group with 1-6 carbon atoms; n is an integer of 1 or 2; and * represents an asymmetric carbon atom, provided that R.sub.2 is a chlorine atom when R.sub.1 is a hydroxyl group); and a method for producing the optically active .alpha.-substituted carboxylic acid derivative represented by the general formula (I) and antipodes thereof using a culture, cells or a material obtainable from cells of a microorganism having an ability to asymmetrically hydrolyze ester bonds. The optically active .alpha.-substituted carboxylic acid derivatives and antipodes thereof provided by the invention are useful as raw materials for various liquid crystals and as synthetic intermediates for various optically active medicines or agricultural chemicals.
摘要:
SATURATED ALIPHATIC ACIDS UNSUBSTITUTED IN THE A-POSITION ARE BROMINATED IN THE ALPHA POSITION BY REACTING THE ACID WITH ELEMENTAL BROMINE IN THE PRESENCE OF A CARBONYL HALIDE OF THE FORMULA
R-CO-X
WHEREIN X IS BROMINE OR CHLORINE AND R IS BROMINE OR CHLORINE.