Shin-etsu Chemical Co., Ltd.

Masahiro Usuki

Susumu Ueno

Mikio Watanabe

Tadashi Amano

Hajime Kitamura

Shigehiro Hoshida

Michio Aizawa

Masayoshi Yono

Toshihide Shimizu

Richard W Armentrout

Thomas J Pollock

Minoru Shigemitsu

Makoto Fujiwara

Toshihiko Nakano

Yoshikatsu Tsuchiya

Kentaro Yamanaka

Toyotaro Kuniyasu

Provided is an addition condensation product of an aromatic compound and a carbonyl compound. The addition condensation product includes an aromatic compound dimer in which two composition units derived from the aromatic compounds are bonded via one composition unit derived from the carbonyl compound and an aromatic compound multimer in which each of three or more composition units derived from the aromatic compounds is bonded via one composition unit derived from the carbonyl compound. A ratio of the aromatic compound dimer to the aromatic compound multimer is in the range of 1:75 to 1:1,000.

Addition condensation product, production method and use of same, polymerization vessel, and production method of polymer

A flexible metal foil/polyimide laminate is prepared by applying a polyamic acid varnish onto a very thin copper foil on a carrier, semi-drying the varnish, laminating a polyimide film to the varnish-coated copper foil using a hot roll press, and heat treating the laminate for solvent removal and imidization in an atmosphere having a controlled oxygen concentration. A polyimide adhesive layer resulting from the imidization of polyamic acid has a thickness of up to 6 &#x3bc;m, the sum of the thicknesses of the polyimide film and the polyimide adhesive layer is up to 25 &#x3bc;m. The polyimide adhesive layer has a Tg&#x3e;400&#xb0; C.

Preparation of flexible copper foil/polyimide laminate

A polyimide precursor resin solution composition sheet having a solvent content of 1&#x2013;50% by weight and a thickness of 1&#x2013;10 microns has improved adhesion, forms a heat resistant polyimide layer when cured, and is advantageously used in the bonding of conductors to plastic films.

Polyimide precursor resin solution composition sheet

A process is provided for producing a vinyl chloride-based polymer by polymerization of vinyl chloride or a monomer mixture containing it in a reaction vessel. Heat generated during polymerization is removed using a reflux condenser. When the polymerization rate is within a range from 30% to 50%, a copolymeric polyether, with a weight average molecular weight of 1,500,000 to 2,000,000, and an ethylene oxide to propylene oxide molar ratio within a range from 78/22 to 82/18, is added to the reaction mass. Foaming of the polymer slurry due to the use of the reflux condenser beyond the point where the polymerization rate reaches 60% is suppressed, and the polymer can be produced with no deleterious effects on the quality of the product polymer.

Process for producing vinyl chloride-based polymer

A method of producing a vinyl chloride-based polymer by suspension polymerization is provided, by which heat removal performed by a reflux condenser can be increased, but total heat removal performed by the jacket can be reduced, without affecting the quality of the product polymer. The method includes commencing heat removal when or after a polymerization conversion rate reaches 15%, and controlling said reflux condenser so as to remove a fixed quantity of heat per unit of time depending on the polymerization conversion rate as the polymerization process proceeds.

Method of producing of vinyl chloride-based polymer

Vinyl chloride or a monomer mixture containing it transported over a long distance or stored for a long period usually contains a polymerization inhibitor and Fe ions. If this kind of vinyl chloride or monomer mixture is polymerized, stirring torque during the polymerization increases, and heat removal by the cooling jacket of a polymerization vessel tends to become insufficient, making the polymer quality subject to bad influences. In the present invention, a hydroxycarboxylic acid compound is added to the polymerization mixture in an amount of 50-1000 ppm relative to the monomer or monomer mixture. As a result, an increase in stirring torque during polymerization is suppressed, and heat removal by the cooling jacket of the polymerization vessel can be performed effectively, making it possible to obtain vinyl chloride of good quality.

Polymerization of vinyl chloride with hydroxycarboxylic acids, inhibitors and Fe ions

A polymer scale deposition preventive agent comprising (a) an aromatic compound having at least eight conjugated .pi. bonds and having a molecular weight of 1,000 or more, and (b) a polyalkylene oxide having a weight-average molecular weight of 2,000 or more, wherein the weight ratio of the component (a) to the component (b) is 100/500 to 100/1, can prevent surely the deposition of polymer scale even in a polymerization system containing a monomer, such as styrene, acrylic acid esters or acrylonitrile, which has a high solvency for a coating film consisting of the conventional polymer scale deposition preventive agent.

Polymer scale depostion preventive agent and a process for producing

A process to prevent scale adhesion on rector surfaces when polymerizing vinyl esters, vinyl esthers, carboxylic acids, styrene or diene monomers. Coating of internal reactor surfaces with a combination of an amino containing aromatic compound, and an alkali metal or ammonium salt of polyvinylsulfuric acid results in the scale prevention. This combination is applied to reactor surfaces via its mixture with a solvent and is subsequently dried to form the coating.

Process to prevent polymer scale adhesion using an aromatic compound and

A process to prevent scale adhesion on reactor surfaces when polymerizing vinyl monomers. Coating of internal reactor surfaces with a combination of an amino containing aromatic compound, and an alkali metal or ammonium salt of polyvinylsulfuric acid results in the scale prevention. This combination is applied to reactor surfaces via its mixture with a solvent and is subsequently dried to form the coating.

A polymer scale preventive agent for use in polymerization of a monomer having an ethylenically unsaturated double bond, comprising:

Polymer scale preventive agent, polymerization vessel effective in

A polymer scale preventive agent for use in polymerization of vinyl chloride monomer or a monomer mixture containing vinyl chloride monomer as a major component, comprising:

Polymer scale preventive agent from naphthoquinone dye

A polymer scale preventive agent for use in polymerization of a haloethylene or a monomer mixture containing the same, comprising: (A) an aromatic compound having at least one group selected from the class consisting of primary, secondary and tertiary amino groups, quaternary ammonium groups and the azo group and/or a dye having at least one group selected from said class, and

A method of preventing polymer scale deposition in a polymerization vessel in polymerization of a particular monomer having an ethylenic double bond having a high dissolving power against the conventional scale preventive coatings, wherein said polymerization is carried out in a polymerization vessel of which the inner wall has been previously coated with a first coating liquid comprising:

Method of preventing polymer scale deposition

Polymer scale deposition from a polymerization medium in which a monomer having an ethylenic double bond is polymerized, is prevented by conducting the polymerization in a polymerization vessel having a coating by applying a liquid comprising (A) an organic compound containing at least one member selected from the group consisting of a sulfonic acid group and a carboxylic acid group and having a molecular weight of 1000 or less and (B) a water-insoluble compound having an absorption band in the visible light range of 540 to 750 nm, the compounds (A) and (B) having been dissolved or dispersed in (C) an ester-based organic solvent, and having a pH of 3 or less; to the inner wall surfaces of said polymerization vessel. Polymer scale can be effectively prevented and polymeric products are barely colored.

Method of preventing polymer scale deposition and polymer scale

A method of preventing polymer scale deposition in a polymerization vessel in polymerization of a particular monomer having an ethylenic double bond having a high dissolving power against the conventional scale preventive coatings, wherein said polymerization is carried out in a polymerization vessel of which the inner wall has been previously coated with a first coating solution comprising:

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Kamisu, Japan

Masahiro Usuki