Nippon Zeon Company, Ltd.

Other

Zeon Corporation

National Institute of Advanced Industrial Science and Technology

Japan Chemical Innovation Institute

Toshio Kase

Hiroyuki Ozaki

Hiroyuki Watanabe

Masahide Murata

Shuichi Akita

Michihiko Asai

Masanao Kawabe

Kohkichi Noguchi

Kenji Tsuchihara

Yoshifumi Fukui

Akira Miyazawa

Yasuzo Suzuki

Kazuo Soga

Hideaki Hagihara

Jizhu Jin

Haruki Kawada

Hideaki Hagiwara

Mitsuyoshi Aonuma

Akio Ueda

The Ban Hoang

Shizuo Kitahara

Tetsuo Ohyama

Takeshi Shiono

Hisae Soga

Jizhy Jin

[Problem] To provide a conjugated diene polymer cyclized product free from coloring, a conjugated diene polymer cyclized product that has a narrow molecular weight distribution and is free from coloring, and a method for producing these conjugated diene polymer cyclized products. [Means for Resolution] A conjugated diene polymer cyclized product having a Gardner color scale of not more than 3.0. A conjugated diene polymer cyclized product having a Gardner color scale of not more than 3.0 and a ratio of weight average molecular weight/number average molecular weight of not more than 1.5. A method for producing a conjugated diene polymer cyclized product includes adding water to a conjugated diene polymer solution obtained by polymerizing a conjugated diene in a solvent by using an organoalkali metal compound as an initiator, thereby terminating the polymerization and then subjecting the subject conjugated diene polymer to a cyclization reaction.

Conjugated diene polymer cyclized product and method for producing the same

A main object of the invention is to provide a polar-group-containing cyclized rubber making it possible to improve remarkable the adhesiveness between paint and a molded product made of a nonpolar polymer such as polypropylene or polyethylene, and a process for producing the same. In order to attain the object, the invention provides a polar-group-containing cyclized rubber which has a polar group at a terminal of a polymer chain thereof, has a weight-average molecular weight of 1000 to 1,000,000, and is obtained by cyclizing a conjugated diene polymer having the polar group at a terminal of a polymer chain thereof.

Polar-group-containing cyclized rubber and process for producing same

A syndiotactic styrenic polymer having a narrow molecular weight distribution which is a (co)polymer comprising at least one structural unit represented by the following Formula (1):wherein Cof a phenyl group thereof has a tacticity of 30% or more in terms of a racemic pentad determined byC-NMR, and Rand m are as defined in the specification. The disclosure is also directed to a block copolymer comprising the above polymer as one segment, to a block graft polymer prepared by modifying one block of the above polymer with a nitrogen-containing aromatic polymer, and to a process for preparing a syndiotactic styrenic polymer in which a styrenic monomer is polymerized in the presence of a catalyst comprising a reaction product of a transition metal compound and at least one co-catalyst selected from organic aluminunoxy compounds.

Syndiotactic styrene polymers and process for the production thereof

A process for preparing olefinic living polymers having a molecular weight distribution (Mw/Mn) of 1 to 1.3, comprising polymerizing an olefinic monomer having 2 to 20 carbon atoms at low temperatures in the presence of a catalyst comprising (A) a hafnium or zirconium-containing compound having one or two cyclopentadienyl backbones, (B) a triphenyl boron compound or a tetraphenyl borate compound and optionally (C) a specific mono-, di- or trialkylaluminum compound. When the catalyst comprising the zirconium-containing compound is prepared by further using a titanium-containing compound (D), the polymerization temperature can be raised.

Process for producing olefin living polymer

A butadiene polymer (i) having a cis bond unit content of at least 50% based on the total butadiene units, a number average molecular weight (Mn) of 1,000 to 10,000,000, and at least 80%, based on the total molecular chains, of living chains containing a transition metal of group IV of the Periodic table at a terminal thereof; a polymer (ii) obtained by modifying terminals of the polymer (i); and a polymer (iii) obtained by coupling the polymers (i). These polymers (i), (ii) and (iii) are obtained by polymerizing a conjugated diene monomer alone or with a copolymerizable monomer at a specific temperature in the presence of a catalyst comprising a compound (A) of a transition metal of group IV of the periodic table having a cyclopentadienyl structure and a co-catalyst (B) selected from organoaluminum-oxy compound (a) and others and optionally further by contacting the resultant polymer with a terminal modifier or a coupling agent.

Butadiene polymers and process for producing conjugated diene polymers

A process for modifying a polymer of a conjugated diene, which comprises reacting a polymer of a conjugated diene containing at least one metal selected from alkali metals and alkaline earth metals with a compound having a linkage of the following formula ##STR1## wherein X represents an oxygen or sulfur atom, in the molecule.

Process for modifying conjugated diene polymers

A process for making a diene polymer rubber which comprises reacting an active diene polymer rubber having alkali metal and/or alkaline earth metal terminals, which is obtained by polymerizing a conjugated diene monomer alone or together with an aromatic vinyl monomer in a hydrocarbon solvent, using an alkali metal and/or alkaline earth metal initiator, with

Process for making diene polymer rubbers

A process for making a diene copolymer rubber having improved rebound, which comprises polymerizing a conjugated diene monomer with an aromatic vinyl monomer in a hydrocarbon solvent in the presence of an alkali metal and/or alkaline earth metal initiator, to form a dienyl-metal terminated, conjugated diene-aromatic vinyl copolymer rubber, and thereafter reacting the copolymer rubber with at least one reactant selected from the group consisting of aminoaldehydes, aminoketones, aminothioaldehydes and aminothioketones.

Process for making diene copolymer rubbers

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Tokyo, Japan

Toshio Kase