Abstract: A viscosity index improver for addition to lubricating oil or the like, which comprises a graft copolymer having structural units of an oil-soluble polymer (a) comprising an olefin polymer and structural units of a copolymer (b) of a monomer having a peroxide bond with a (meth)acrylate or the like or a copolymer (c) of a monomer having a peroxide bond with 2-hydroxyethyl(meth)acrylate or the like. The improver is excellent in the effect of improving the viscosity index, the thickening effect, the fluidity at low temperatures and the shear stability, and has no fear of causing phase separation in lubricating oil.

Abstract: A resin composition for polymerization casting containing:20 to 60% by weight of a monomer (1) represented by the formula (1) ##STR1## wherein R.sup.1 stands for a hydrogen atom or a methyl group, R.sup.2 stands for an alkylene group having 2 to 4 carbon atoms, m and n each is an integer of 2 to 5;10 to 40% by weight of a monomer (2) represented by the formula (2) ##STR2## wherein R.sup.3 stands for a hydrogen atom or a methyl group, R.sup.4 and R.sup.5 are the same or different groups and each stands for an alkylene group having 2 to 4 carbon atoms, j and k each is 0 or 1; and5 to 70% by weight of a monomer (3), the monomer (3) being identical with neither monomers (1) nor (2), and containing at least one vinyl group in a molecule thereof.

Abstract: A vulcanizable rubber composition which contains an iodine- or bromine-containing rubber and an organic peroxide of the formula. ##STR1## wherein R.sup.1 is a hydrogen atom, a chlorine atom or methyl group, R.sup.2 is a linear or branched alkyl group having 2 to 5 carbon atoms, and n is an integer of 1 to 3, generates only a small amount of methyl iodide or methyl bromide during the vulcanization.

Abstract: A 1-cyclohexyl-1-methylethylperoxy carbonate represented by the formula: ##STR1## (wherein n.sub.1 stands for 1 or 2 and, when n.sub.1 is 1, R.sub.1 stands for an alkyl group of up to 14 carbon atoms, an aralkyl group of up to 14 carbon atoms, an alkoxyalkyl group of up to 14 carbon atoms, a cycloalkyl group of up to 14 carbon atoms, or an aryl group of up to 14 carbon atoms, and when n.sub.1 is 2, R.sub.1 stands for an alkylene group of up to 16 carbon atoms, an aralkylene group of up to 16 carbon atoms, an oxaalkylene group of up to 16 carbon atoms, a cycloalkylene group of up to 16 carbon atoms, or a phenylene group of up to 16 carbon atoms) is a novel compound. It is produced by causing a chloroformate represented by the formula: ##STR2## (wherein n.sub.2 has the same meaning as n.sub.1 in the preceding formula) to react with 1-cyclohexyl-1-methylethylhydroperoxide.

Abstract: A composition for cross-linking of ethylene.polymer comprises 2,4-diphenyl-4-methyl-1-pentene and at least one peroxide selected from the group consisting of [1] peroxides represented by the formula (I): ##STR1## (wherein R.sup.1 stands for one member selected from the group consisting of alkyl groups, aryl groups, and alkyl-substituted aryl groups having 1 to 9 carbon atoms, R.sup.2 for one member selected from the group consisting of phenylene group, ethylene group, --C.tbd.C--, and alkyl groups, aryl groups, and alkyl-substituted aryl groups having 1 to 9 carbon atoms, and n for 1 or 2) and [2] peroxides represented by the formula (II): ##STR2## (wherein two R.sup.3 's independently stand for one member selected from the group consisting of alkyl groups, aryl groups, and alkyl-substituted aryl groups of 1 to 9 carbon atoms or jointly stand for an ethylene group, R.sup.4 and R.sup.5 independently stand for a linear or branched alkyl group of 1 to 6 carbon atoms or --(CH.sub.2).sub.m C(O)OR.sup.6 [wherein R.

Abstract: A vulcanizable rubber composition which contains an iodine- or bromine-containing rubber and an organic peroxide of the formula: ##STR1## wherein R.sup.1 is a hydrogen atom, a chlorine atoms or methyl group, R.sup.2 is a linear or branched alkyl group having 2 to 5 carbon atoms, and n is an integer of 1 to 3, generates only a small amount of methyl iodide or methyl bromide during the vulcanization.

Abstract: An organic peroxide consisting of 1 to 30 repeating units represented by the formula ##STR1## wherein R stands for one group selected from the class consisting of ethylene, acetylene, cyclohexylene, and phenylene groups and one of 1 and m stands for an integer of at least 1 and 1+m stands for an integer in the range of from 6 to 220. Polymerization initiator for a vinyl monomer consisting of the organic peroxide mentioned above. A method for polymerizing a vinyl monomer by using the polymerization initiator mentioned above.

Abstract: An ester type polymeric peroxide; has a peroxide group of the formula (I): ##STR1## a group of the formula (I') ##STR2## a group of the formula (II) ##STR3## wherein X stands for one member selected from the group consisting of --CH.sub.2 --CH.sub.2 --, --C.tbd.C-- and ##STR4## continuously bound such that I and I' occur randomly in alternation with II, having a (I):(I') molar ratio in the range of from 9:1 to 1:9 and the [(I)+(I')]:(II) molar ratio in the range of from 6:4 to 4:6, and having an average molecular weight in the range of from 1,000 to 20,000, a polymerization initiator for vinyl type monomer comprising said ester type polymeric peroxide and method for the production of a block copolymer of vinyl type monomer by said polymerization initiator.

Abstract: A composition for cross linking an ethylene polymer comprises an organic peroxide as a cross linking agent and a compound represented by the formula: ##STR1## wherein R stands for a hydrogen atom or one member selected from the class consisting of alkyl groups of 1 to 9 carbon atoms and n is an integer of 2 or 3. A method for cross linking the ethylene type polymer uses the composition mentioned above. An electric power cable comprises a core coated with resinous layers produced by the method described above.

Abstract: A 1-cyclohexyl-1-methylethyl peroxy ester, a novel compound, represented by the formula: ##STR1## wherein R.sup.1 stands for one member selected from the group consisting of H and alkyl groups and R.sup.2 and R.sup.3 independently stand for an alkyl group, provided that R.sup.2 and R.sup.3 each stand for an alkyl group of 1 to 5 carbon atoms and the sum of the carbon atoms of R.sup.2 and R.sup.3 is in the range of from 2 to 6 where R.sup.1 is H and R.sup.1, R.sup.2, and R.sup.3 each stand for an alkyl group of 1 to 9 carbon atoms and the sum of the carbon atoms of R.sup.1, R.sup.2, and R.sup.3 is in the range of from 3 to 11 where R.sup.1 is an alkyl group, a polymerization initiator for a vinyl group-containing compound monomer and a curing agent for an unsaturated polyester resin, which polymerization initiator and curing agent both contain as an active component thereof the ester mentioned above.

Abstract: A novel dialkyl peroxide is represented by a general formula (I): ##STR1## This peroxide is produced by particular methods and used as a photolysis type or pyrolysis type radical forming agent.

Abstract: A novel peroxy ester represented by the general formula (I): ##STR1## is useful as a polymerization initiator for vinyl chloride monomer.

Abstract: A polyvinyl chloride polymer or copolymer having excellent thermal resistance and being free from FEs and offensive smell can be obtained in a high yield through a polymerization reaction of vinyl chloride monomer alone or together with a vinyl monomer copolymerizable therewith by the use of a combination system polymerization initiator consisting of (A) .alpha.,.alpha.'-bis(neodecanoylperoxy)-diisopropylbenzene, and (B) at least one of peroxy ester, diacyl peroxide and peroxy dicarbonate, each of which has a 10-hour half-life period temperature within the range of 40.degree.-65.degree. C. in its 0.1 mol concentration solution in benzene.

Abstract: A polymeric peroxy ester, which consists of a structural unit represented by the formula (I): ##STR1## and a structural unit represented by the general formula (II): ##STR2## wherein R represents --CH.sub.2 CH.sub.2 --, --C.tbd.C-- or ##STR3## and had an average molecular weight or 1,000-15,000, said structural units (I) and (II) being bonded alternately in a molar ratio within the range of from 6:4 to 4:6, has a 10-hour half-life period temperature of 70.degree.-85.degree. C. and a high activity at relatively high temperature, is safe in the production and handling, is adapted to be used as a polymerization initiator in the polymerization of vinyl monomer, and can produce a vinyl polymer having a high molecular weight.

Abstract: A novel peracid ester represented by the general formula (I): ##STR1## is useful as a polymerization initiator for vinyl chloride monomer, a curing agent for unsaturated polyester resin or a crosslinking agent for polymers.

Abstract: A novel polymeric peroxide used as a free radical polymerization initiator for vinyl monomers is a compound alternately bonding the two particular structural units in random form and having two different thermal decomposition rates.

Abstract: High-purity 1,1,3,3-tetramethylbutyl hydroperoxide can be easily and safely produced without the formation of dangerous acetone peroxide, by the reaction of neopentyldimethylcarbinol with hydrogen peroxide in the presence of sulfuric acid.

Abstract: Excellent polymers of vinyl chloride series monomers having a good thermostability to prevent coloring and not having displeasant odor can be provided with even polymerization speed at high yield by using a specific combination system of a fast initiator and retarded initiators.

Abstract: Two molecules of mono-substituted acetaldehyde having the following general formula (I) and one molecule of organic halide having the following general formula (II) are reacted in an alkaline aqueous solution in the presence of a phase transfer catalyst whereby a .beta.-.gamma.-unsaturated aldehyde having the general formula (III) as shown in the following reaction scheme (A) is obtained directly from the monosubstituted acetaldehyde without forming an .alpha.,.beta.-unsaturated aldehyde ##STR1## wherein R.sub.1 is straight chain or branched chain alkyl, alkenyl, cycloalkyl or aryl, R.sub.2 is allyl, substituted allyl, propargyl, substituted propargyl, benzyl or substituted benzyl, and X is halogen.