摘要:
1,1,1,2-tetrafluoroethane (134a) is prepared by reacting, in the gas phase, trichloroethylene with 1,1,1-trifluorochloroethane (133a) and hydrofluoric acid with trichloroethylene/133a molar ratios ranging from 5/95 to 50/50, in the presence of a catalyst consisting of Cr.sub.2 O.sub.3 carried on AlF.sub.3.The process provides 134a yields higher than 90% and permits an exceptionally long life of the catalyst. In this way it is possible to realize a continuous process by recycling the unreacted trichloroethylene and 133a, thereby making up for the relatively low global conversion of the reagents.
摘要:
This invention relates to perfluoropolyethers having neutral end groups by a process based on the photooxidation of C.sub.3 F.sub.6 and/or C.sub.2 F.sub.4, thereby obtaining controlled molecular weight products having perfluoroalkyl or perfluorochloroalkyl neutral end groups, with high yields of useful products.
摘要:
Amino-derivative (poly)peroxycarboxylic acids which have the formula: ##STR1## wherein the symbols have the following meanings: R, R.sub.1, and R.sub.2, which may be equal to or different from one another, represent hydrogen atoms, alkyl groups or groups selected from R, R.sub.1 and R.sub.2, which taken together with the nitrogen atom to which they are linked, give rise to an aliphatic heterocyclic group, all of them being optionally substituted;A represents a (cyclo) alkylene group, an arylene group which may also be condensed with cycloaliphatic groups, a cycloalkylene-alkylene or an alkylene-cycloalkylene group, an arylene-alkylene or an alkylene-arylene group, which may be condensed with cyclo-aliphatic groups, wherein said alkylene group may also be interrupted by --CONR.sub.3 groups, wherein R.sub.3 represents a hydrogen atom or an alkyl or aryl group;X- represents HSO.sub.4.sup.- or CH.sub.3 SO.sub.3.sup.- ;a process for their preparation; and their use as bleaching agents.
摘要:
A process for preparing fluorinated compounds belonging to the classes:XH--Y--CZ.sub.1 Z.sub.2 --(CF.sub.2).sub.n F (I)andYH--X--(CF.sub.2).sub.n --CZ.sub.1 Z.sub.2 F (II)wherein:X is NR.sub.x, O, S, CFR.sub.x, C(R.sub.x).sub.2, or CF.sub.2 ;Y is NR.sub.x, O, S, CFR.sub.x, C(R.sub.x).sub.2, or CF.sub.2 ;X is different from Y;R.sub.x is a perhalogenated alkyl group, containing from 1 to 4 carbon atoms;n is either 0 or 1;Z.sub.1 and Z.sub.2, which may be either equal to, or different from, each other, represent F, Cl, Br, H or R.sub.x.The process is characterized in that a fluorinated cyclic compound of the formula: ##STR1## is reacted, at a temperature within the range of from -80.degree. to +300.degree., with HF in the presence of a Lewis acid. Some of the so-obtained compounds per se are novel.
摘要:
Amino-derivative (poly)peroxycarboxylic acids which have the formula: ##STR1## wherein the symbols have the following meanings: R, R.sub.1, and R.sub.2, which may be equal to or different from one another, represent hydrogen atoms, alkyl groups or groups selected from R, R.sub.1 and R.sub.2, which taken together with the nitrogen atom to which they are linked, give rise to an aliphatic heterocyclic group, all of them being optionally substituted;A represents a (cyclo) alkylene group, an arylene group which may also be condensed with cycloaliphatic groups, a cycloalkylene-alkylene or an alkylene-cycloalkylene group, an arylene-alkylene or an alkylene-arylene group, which may be condensed with cyclo-aliphatic groups wherein said alkylene group may also be interrupted by --CONR.sub.3 groups, wherein R.sub.3 represents a hydrogen atom or an alkyl or aryl group;X.sup.- represents HSO.sub.4.sup.- or CH.sub.3 SO.sub.3.sup.- ; a process for their preparation; and their use as bleaching agents.
摘要:
Fluoroelastomers characterized by the presence of iodine or bromine atoms at the end of the polymeric chain in an amount equal to or lower than 1 iodine or bromine atom per polymeric chain, and by a bromine content in the chain ranging from 0.05 to 2% by weight referred to the total weight of the monomeric units.Said fluoroelastomers exhibit improved characteristics of processability, particularly as regards the utilization in injection molding processes and the detaching from the molds, as well as of stability to heat.A process for preparing fluoroelastomers containing iodine or bromine atoms at the ends of the polymeric chain, in an amount equal to or lower than 1 iodine or bromine atom per polymeric chain, which process comprises polymerizing mixes of fluorinated monomers (VDF, TFE, HFP, FVE) in bulk, in suspension, in aqueous emulsion, or in solution of organic solvents by means of radical starters, in the presence of compounds capable of providing I.sup.- or Br.sup.- ions in the polymerization medium and conditions.
摘要:
An antirust additive for lubricants based on perfluoropolyethers, comprising one of the fluoropolyether compounds having functionalized end groups selected from --CN, --CH.sub.2 NR.sub.1 R.sub.2 and ##STR1## and in particular a combination of these with small amounts of a fluoropolyether with acid end groups.
摘要翻译:一种用于基于全氟聚醚的润滑剂的防锈添加剂,其包含具有选自-CN,-CH 2 NR 1 R 2和的官能化端基的氟聚醚化合物之一,特别是这些与少量具有酸端基的含氟聚醚的组合。
摘要:
Functional polyolefins containing a terminal functional group; the block copolymers that can be obtained from such polyolefins by reaction with polymers reactive with the functional groups and the precursors used for the preparation of the functionalized polyolefins, which are made of olefin polymers terminated at one end with ZnR groups where R is an alkyl or aryl radical with 1-10 carbon atoms.
摘要:
Heterocyclic (poly)peroxycarboxylic acids having a N-amidic heteroatom, which have the formula:R--(CH.sub.2) .sub.m --R' (I)wherein: R and R', alike or different from each other, represent hydrogen atoms or a group: ##STR1## with the proviso that at least one of R and R' shall be different from H, and wherein the other symbols have the following meaning:R" represents a hydrogen atom or any other substituent non-reactive in the presence of the active oxygen of the peroxycarboxylic group and/or under the preparation conditions;m represents a number between 1 to 12;n represents a number selected from 0, 1 and 2;p represents a number between 1 and 3;their process of preparation and their use as bleaching agents.
摘要:
Maleic anhydride is grafted onto unsaturated elastomeric terpolymers consisting of monomeric units coming from at least two different monomers having the formula R--CH.dbd.CH.sub.2 (R=hydrogen or an alkyl group containing from 1 to 6 carbon atoms) and from a conjugated or non-conjugated dienic monomer by mass reaction, which is carried out by heating at 120.degree.-350.degree. C. a mixture of said maleic anhydride with the terpolymer in the presence of a catalyst consisting of a compound having the formula:M.sub.n X.sub.zwherein:M=a metal of group VIII of the periodic system, and in particular Rh and Ru;X=a counterion,N=valence of the counterion; andZ=valence of the metal.