摘要:
A photopolymerizable recording composition for water-washable printing plates, which comprises:(a) a water dispersible elastomeric blend of at least 20 percent by weight of an A-B-M-B-A block copolymer and an A-B-M block copolymer, wherein A is a vinyl aromatic hydrocarbon block, B is a conjugated diene block and M is an acrylic monomer block containing acid groups, and(b) a photopolymerization initiator.
摘要:
The anionic polymerization of unsaturated monomers with functionalized initiators having the structure R.sup.1 R.sup.2 R.sup.3 Si--O--A'--Li is improved by selecting A' from the structures --CH.sub.2 --CH.sub.2 --CH.sub.2 --(1,3-propyl), --CH.sub.2 --CH(CH.sub.3)--CH.sub.2 --(2-methyl-1,3-propyl), --CH.sub.2 --C(CH.sub.3).sub.2 --CH.sub.2 --(2,2-dimethyl-1,3-propyl), or --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --(1,8-octyl). This narrow class of polymerization initiators operate at surprisingly higher polymerization temperatures with surprisingly lower amounts of dead initiator than similar initiators wherein A' is --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --(1,4-butyl), --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --(1,5-pentyl), or --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 13 CH.sub.2 --(1,6-hexyl).
摘要:
The anionic polymerization of isoprene with monolithium initiators and functionalized initiators having the structure R.sup.1 R.sup.2 R.sup.3 Si--O--A'--Li wherein R.sup.1, R.sup.2, and R.sup.3 are preferably alkyl, alkoxy, aryl, or alkaryl groups having from 1 to 10 carbon atoms, and A' is preferably a branched or straight chain bridging group having at least 2 carbon atoms produces unsaturated and hydrogenated isoprene polymers having high 1,4-addition of the isoprene, from about one to two terminal functional groups per molecule, and low viscosity.
摘要:
A process for making polymers of conjugated dienes which contain hydroxyl groups in the diene blocks which comprises(a) making a precursor polymer by polymerizing at least one conjugated diene which leaves 1,2 disubstituted, 1,1 disubstituted, 1,1,2 trisubstituted or tetrasubstituted olefinic unsaturation in the polymer,(b) optionally partially hydrogenating said precursor polymer,(c) epoxidizing said precursor polymer such that epoxy groups form at said substituted sites and the amount of epoxy functionality in the polymer is from 0.1 to 5 Meq/g polymer, and(d) reacting the epoxidized polymer with an alcohol solution of hydrochloric acid.A diene polymer containing 0.1 to 10 Meq/g polymer of hydroxyl group and comprised of alcohol units of the formula ##STR1## where R.sub.1 and R.sub.2 are hydrogen or alkyl radicals and X and X' are either --OH or --Cl and at least one of them is --OH.
摘要:
A process for making polymers of conjugated dienes which contain hydroxyl groups, including highly reactive primary hydroxyl groups, in the diene blocks which comprises(a) making a precursor polymer by polymerizing at least one conjugated diene which leaves 1,2 disubstituted, 1,1 disubstituted, 1,1,2 trisubstituted or tetrasubstituted olefinic unsaturation in the polymer,(b) optionally partially hydrogenating said precursor polymer,(c) epoxidizing said precursor polymer such that epoxy groups form at said substituted sites and the amount of epoxy functionality in the polymer is from at least 0.1 Meq/g polymer, and(d) reacting the epoxidized polymer with an alcohol having one unprotected hydroxyl group in a solvent in the presence of a Lewis acid selected from the group consisting of MX.sub.n where M is selected from the group consisting of boron, aluminum, iron and tin, and X is a halogen, and organic complexes of such acids.A diene polymer containing 0.01 to 15 Meq/g polymer of hydroxyl group, preferably including highly reactive primary hydroxyl groups, and comprised of ether-alcohol units of the formula ##STR1## where R is selected from the group consisting of alkyl radicals containing up to 10 carbon atoms, monohydric and dihydric alcohol groups and carbonate groups; and R.sub.1 and R.sub.2 are hydrogen or alkyl radicals wherein in (G) only one of R.sub.1 or R.sub.2 is hydrogen.
摘要:
A method of oxidizing the surface of carbon microfibers that includes contacting the microfibers with an oxidizing agent that includes sulfuric acid and potassium chlorate under reaction conditions sufficient to oxidize the surface. The invention also features a method of decreasing the length of carbon microfibers that includes contacting the microfibers with an oxidizing agent under reaction conditions sufficient to decrease the length.
摘要:
Lithium-terminated polymers of one or more conjugated dienes and of one or more mono alkenyl arenes are coupled by reaction with an alkoxy silane coupling agent having the formula Rx—Si—(OR′)y, where x is 0 or 1, x+y=4, R and R′ are the same or different, R is selected from aryl hydrocarbon radicals, linear alkyl hydrocarbon radicals and branched alkyl hydrocarbon radicals, and R′ is selected from linear and branched alkyl hydrocarbon radicals, such that the resulting polymer composition contains less than about ten weight percent of uncoupled polymer diblock. The polymer compositions are subsequently selectively hydrogenated, and are useful in a variety of compounds and end use applications.
摘要翻译:通过与具有式Rx-Si-(OR')y的烷氧基硅烷偶联剂反应将一个或多个共轭二烯和一个或多个单链烯基芳烃的锂封端的聚合物偶联,其中x为0或1,x + y = 4,R和R'相同或不同,R选自芳基烃基,直链烷基烃基和支链烷基烃基,R'选自直链和支链烷基烃基,使得所得聚合物 组合物含有小于约10重量%的未偶联的聚合物二嵌段。 聚合物组合物随后被选择性氢化,并且可用于各种化合物和最终用途。
摘要:
The present invention relates to novel compositions comprising (a) anionic block copolymers of mono alkenyl arenes and conjugated dienes, and (b) tailored softening modifiers have a particular polydispersity index that results in a surprising improvement in properties for the composition. Also included are processes for the manufacturing such novel compositions and various end-uses and applications for such compositions.
摘要:
The present invention provides a block copolymer composition and method of making the same having the structures (A2-B)n-X-(A1) or (A2-B2)n-X-(B1A1), where A1 and A2 are each a polymer block of a monoalkenyl arene and B, B1, and B2 are each a polymer block of one or more conjugated dienes or a hydrogenated diene polymer, n is an integer from 2 to 30 and X is the residue of a coupling agent.
摘要:
The present invention is a novel block copolymer containing a controlled distribution copolymer block of a conjugated diene and a mono alkenyl arene, where the controlled distribution copolymer block has terminal regions that are rich in conjugated diene units and a center region that is rich in mono alkenyl arene units. Also disclosed is a method for manufacture of the block copolymer.