Mitsubishi Rayon Company, Limited

Seiji Tone

Masahiro Sugimori

Haruko Takeda

Akira Yanagase

Toru Tokimitsu

Naoki Yamamoto

Hiroshi Mori

Akira Nakata

Hitoshi Ige

Mitsufumi Nodono

Hajime Yasuda

Eiji Ihara

A copolymer having low birefringence substantially consisting of a repeating unit represented by the following general formula (1) and a repeating unit of a (meth)acrylate:

Lowly birefringent polymer, process for the production thereof, and optical pickup lens

Process for the preparation of poly(meth)acrylic acid ester

Block copolymer and a preparation process thereof

A method for preparing a graft copolymer is here disclosed which is characterized by comprising the step of carrying out a living polymerization of at least one (meth)acrylic ester by the use of a polymeric compound as an initiator having one or more units represented by the following formula (I) in a molecular chain substantially in the absence of water in the presence of a Lewis acid or a donor compound of an anion selected from the group consisting of HF.sub.2.sup.-, (CH.sub.3).sub.3 SiF.sub.2.sup.- and F.sup.- : ##STR1## wherein R is hydrogen or an alkyl group having 1 to 6 carbon atoms, and R' is an alkyl group having 1 to 12 carbon atoms.

Method for preparing graft copolymer

A preparation process of block copolymers which comprises conducting living polymerization of a (meth)acrylic ester substantially in the absence of water, by using a macromolecular compound having a functional end group represented by the formula (1): ##STR1## Wherein R is H or an n-alkyl group having from 1 to 3 carbon atoms and R' is H or an alkyl group having from 1 to 6 carbon atoms, as a polymerization initiator and in the presence of a Lewis acid or in the presence of a donor compound of an anion selected from HF.sub.2.sup.-, (CH.sub.3).sub.3 SiF.sub.2.sup.- or F.sup.-, as well as novel block copolymers prepared therefrom are disclosed.

Preparation process of block copolymers and resulting block copolymers

Oxygen-permeable shaped articles and process for producing same

An antistatic agent capable of imparting a permanent antistatic property to a methacrylic resin is prepared as follows. First, an alkyl methacrylate is subjected to living polymerization in an atmosphere substantially free of water in the pressure of at least one compound acting as a source for supplying an anion selected from HF.sub.2.sup.-, (CH.sub.3).sub.3 SiF.sub.2.sup.- and F.sup.- by using as an initiator a compound represented by the formula (I) or (II): ##STR1## wherein R is H or CH.sub.3 and R.sup.1 is H or alkyl; second, a methacrylic acid ester comprising at least 80 mole % of a methacrylic acid ester represented by the formula (III): ##STR2## wherein R.sup.2 is alkyl and m is from 1 to 6, is subjected to living polymerization in the presence of the polymer obtained in the first step, to prepare a di-block or tri-block copolymer; and then, amino groups of segments derived from the methacrylic acid ester of the formula (III) in the block copolymer are quaternized.

Process for preparation of antistatic agent and methacrylic resin

A comb copolymer consisting of a methacrylic macromonomer as a branch ingredient and acrylic ester as a backbone ingredient and being suitable for an acrylic elastomer material which is excellent in transparency, weatherability and mechanical strength; an impact resistant acrylic resin composition obtained by blending the above comb copolymer with a PMMA (co)polymer; and a comb copolymer similarly consisting of a methacrylic macromonomer as a branch component and acrylic ester as a backbone component and being an acrylic resin which is excellent in transparency, weatherability, gloss and light resistance, are disclosed in this invention. Preparation methods of the high molecular weight comb copolymers useful for molding materials comprising the above mentioned comb copolymers are disclosed. The disclosed preparation methods comprise, in the copolymerization of the macromonomer having a vinyl group at one end of the main chain with a vinyl monomer, conducting aqueous suspension polymerization of the monomer mixture in the presence of an initiator in a solvent which is a good solvent for the macromonomer and has a solubility of 10% by weight or more in water at 30.degree. C., or conducting aqueous suspension polymerization of the monomer mixture in the presence of an initiator in a halogenated hydrocarbon solvent which is a good solvent for the macromonomer and has an azeotropic point with water ranging from 30.degree. to 90.degree. C. at a temperature above said azeotropic point.

Preparation method of comb copolymer, acrylic comb copolymer, and impact

A comb copolymer consisting of a methacrylic macromonomer as a branch ingredient and acrylic ester as a backbone ingredient and being suitable for an acrylic elastomer material which is excellent in transparency, weatherability and mechanical strength; an impact resistant acrylic resin composition obtained by blending the above comb copolymer with a PMMA (co)polymer; and a comb copolymer similarly consisting of a methacrylic macromonomer as a branch component and acrylic ester as a backbone component and being an acrylic resin which is excellent in transparency, weatherability, gloss and light resistance, are disclosed in this invention. Preparation methods of the high molecular weight comb compolymers useful for molding materials comprising the above mentioned comb copolymers are disclosed. The disclosed preparation methods comprise, in the copolymerization of the macromonomer having a vinyl group at one end of the main chain with a vinyl monomer, conducting aqueous suspension polymerization of the monomer mixture in the presence of an initiator in a solvent which is a good solvent for the macromonomer and has a solubility of 10% by weight or more in water at 30.degree. C., or conducting aqueous suspension polymerization of the monomer mixture in the presence of an initiator in a halogenated hydrocarbon solvent which is a good solvent for the macromonomer and has an azeotropic point with water raning from 30.degree. to 90.degree. C. at a temperature above said azeotropic point.

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Ohtake, Japan

Seiji Tone