Abstract: The present invention provides a process for the production of a conjugated diene polymer having a controlled microstructure at a high polymerization activity in the presence of a metallocene type complex of compound of transition metal of the group V of the Periodic Table. A novel catalyst is provided comprising (A) a metallocene type complex of a transition metal of the group V of the Periodic Table, (B) an ionic compound of a non-coordinating anion and a cation, (C) an organic metal compound of the groups I to III and (D) water, wherein the molar ratio of (C)/(D) is from 0.66 to 5.

Abstract: A catalyst obtained by contacting (A) a compound of a transition metal of the group V of the Periodic Table represented by formula (I):R.sub.n M(O).sub.m X.sub.p .cndot.L.sub.

Abstract: Rubber-modified, impact-resistant polystyrene resin compositions having a well balanced combination of improved properties such as tensile strength and tensile elongation as well as reactivity with styrene monomers, impact resistance, low-temperature properties, and gloss, comprise dispersed particles of a rubber polymer which satisfies the following: (1) the content of the rubber polymer in the compositions is from 1 to 25% by weight; (2) the rubber polymer is a high-cis high-vinyl polybutadiene comprising from 65 to 95% cis-1,4-structures and from 30 to 4% 1,2-structures; and (3) the relationship between the 1,4-structures and 1,2-structures of the rubber polymer is represented by the following expression (A), wherein the value of .beta. is in the range of 1.0<.beta..ltoreq.1.43;.beta.=P.sub.1,2-,1-4 /(2.times.P.sub.1,2 .times.P.sub.1,4)(A)wherein P.sub.1,2 represents the content of 1,2-structures, P.sub.1,4 represents the content of 1,4-structures, and P.sub.

Abstract: A high cis-1,4-polybutadiene is produced, with reduced gel formation, by preparing a catalyst from (A) a cobalt compound, (B) a trialkyl (C.sub.1-10) aluminum compound, (C) a halide compound selected from those of formulae (1) and (2): (1) AlR.sup.2.sub.m X.sub.3-m, and (2) R.sup.3 --X, wherein R.sup.2 =C.sub.1-10 hydrocarbon, X=halogen, m=0 to 2, R.sup.3 =C.sub.1-40 hydrocarbon, and (D) water in an amount of 0.77 to 1.45 moles per mole of total Al in components (B) and (C); and polymerizing 1,3-butadiene in the presence of the resultant catalyst in a polymerization medium including an alkane, cycloalkane and/or olefin hydrocarbon.

Abstract: In a process for producing syndiotactic-1,2-polybutadiene by suspension polymerization wherein a mixture composed of 1,3-butadiene, a cobalt compound, and an organometallic compound or metal hydride containing a metal of group I, II or III of the periodic table is contacted with an initiator selected from the group consisting of carbon disulfide, phenyl isothiocyanate and xanthogenic compounds in an aqueous medium, the improvement comprising, after the preparation of the mixture, adding thereto an anti gelling agent selected from the group consisting of alcohols, aldehydes, ketones, carboxylic acid esters, nitriles, sulfoxides, amides and phosphoric acid esters, whereby the formation of a rubber-like gelation product in the mixture is inhibited.

Abstract: An N-(hydroxyphenyl)maleimide-isobutylene copolymer having the following repeating units: ##STR1## wherein R.sup.3 is a halogen atom or a lower alkyl group having 1-5 carbon atoms; l, m and n are numbers satisfying conditions of 0.01<n/(l+m).ltoreq.10 and 0.2<l/(l+m).ltoreq.1; and p is an integer of 0-4.

Abstract: A process for the preparation of an N-(hydroxyphenyl)-5 maleimide copolymer having the following repeating units: ##STR1## wherein R.sup.1 is hydrogen, an aryl group, an alkyl group having 1-16 carbon atoms or a cycloalkyl group; R.sup.2 is hydrogen or a lower alkyl group having 1-5 carbon atoms; R.sup.3 is a halogen atom or a lower alkyl group having 1-5 carbon atoms; l, m and n are numbers satisfying conditions of 0.01<n/(l+m).ltoreq.10 and 0.1<l/(l+m).ltoreq.1; and p is an integer of 0-4, comprising reaction of a copolymer of maleic anhydride and an unsaturated hydrocarbon and an aminophenol in an organic solvent.

Abstract: A process for producing polybutadiene of a high degree of polymerization having high 1,2 and cis-1,4 microstructure contents and a low trans-1,4 microstructure content, which comprises polymerizing 1,3-butadiene in the presence of a catalyst system composed of(1) a halogen-containing organoaluminum compound,(2) (a) a cobalt dithiocarbamate compound or (b) the reaction product of carbon disulfide, a secondary amine and a cobalt compound, and(3) water.The polybutadiene has for example(A) a 1,2 microstructure content of 7 to 50%,(B) a cis-1,4 microstructure content of at least 50%,(C) a trans-1,4-microstructure content of at most 5%,(D) an inherent viscosity, measured in toluene at 30.degree. C., of at least 1, and(E) a gel content of at most 0.3%.

Abstract: Butadiene polymers containing 70% or more of 1,2-structure and a relatively low melting point are produced by polymerizing 1,3-butadiene in the presence of a catalyst which has been prepared by admixing (A) an organic solvent solution containing 1,3-butadiene, a cobalt compound and an organoaluminium compound; (B) an amide compound of the formula (2) or (3): ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3 are respectively an H atom, aliphatic hydrocarbon radical of 1 to 7 carbon atoms or aromatic hydrocarbon radical of 6 or 7 carbon atoms, R.sub.3 is H or an aliphatic hydrocarbon radical of 1 to 3 carbon atoms and n is 2 to 5, and; (C) carbon disulfide.