Nissin Chemical Industry Co., Ltd.

Shin-etsu Chemical Co., Ltd.

Daikin Industries, Ltd.

Nisshin Chemical Industry Co., Ltd.

Nissin Chemical Co., Ltd.

Hiroyuki Ohata

Harukazu Okuda

Kunio Itoh

Motoo Fukushima

Tsutomu Nakamura

Satoshi Terasaki

Masaki Tanaka

Masaharu Takahashi

Tsuyoshi Noguchi

Tetsuo Nakanishi

Toshio Ohba

Masayasu Tomoda

Yasuo Tarumi

Hiroshi Ohashi

Mitsuo Asai

Yoshihiro Shirai

Etsuo Minamino

Kazuhisa Matsumoto

Kiyoji Suemoto

Hiroshi Saga

Hidekazu Iida

Keiichi Uchida

Tsutomu Matsuo

Proposed is an acrylic rubber composition suitable for hot-air vulcanization under normal pressure with a greatly increased vulcanization velocity. The composition comprises:

Acrylic rubber composition

Proposed is an acrylic rubber-based composition suitable for hot-air vulcanization under normal pressure in a continuous process. The rubber composition comprises, besides an acrylic rubber polymer having, in a molecule, at least two silicon-bonded vinyl groups to serve as the crosslinking sites, reinforcing filler and organic peroxide as a vulcanizing agent, an alkoxy silane compound having a vinyl group or (meth)acryloxy group bonded to the silicon atom, such as vinyl triethoxy silane and 3-methacryloxypropyl trimethoxy silane in a specified amount. This unique ingredient serves as a vulcanization accelerator so that the vulcanization reaction is so rapid as to be freed from foaming of the vulcanizate due to the volatile matters and is complete even in the surface layer without the vulcanization-inhibiting influences by the atmospheric oxygen.

Acrylic rubber-based composition

An improved flame-retardant composition and method for its use are provided. The composition imparts flame retardency to synthetic thermoplastic resins to prevent dripping of the melt of the resin when the resin is burnt. The composition comprises a flame retardant agent such as phosphate ester compound, optionally combined with a metal hydroxide, and an organopoly-siloxane-based graft copolymer of a (meth)acrylic acid ester such as methyl(meth)-acrylate. The flame retardant is used in an amount from 1-50 parts by weight per 100 parts by weight of the synthetic resin, and the graft copolymer provides 0.5 to 20 parts by weight of an organosilicone group per 100 parts by weight of the synthetic resin.

Flame retardant composition and method for use in synthetic

Crosslinkable composition

An acrylic rubbery polymer having remarkably improved cold resistance can be prepared by modification with an organopolysiloxane by the emulsion copolymerization of a monomeric mixture of two acrylic monomers, of which one is, for example, an alkyl acrylate and the other is an acrylic compound having, in a molecule, at least one ethylenically unsaturated group other than acrylic group in an aqueous emulsion of an organopolysiloxane having a substantial amount of mercapto-substituted monovalent hydrocarbon groups bonded to the silicon atoms.

Method for the preparation of an acrylic polymer modified with an

The polymeric ingredient of the inventive rubber composition is an acrylic polymer modified with a mercapto-containing organopolysiloxane as prepared by the emulsion polymerization of an acrylic monomer in an aqueous emulsion of the organopolysiloxane. Characteristically, the acrylic monomer is copolymerized with another monomer having an active halogen atom or an epoxy group. By virtue of this unique formulation of the rubbery polymer, the inventive rubber composition prepared by compounding the rubbery polymer with a reinforcing filler and a specified curing or crosslinking agent can be vulcanized to give a vulcanizate having excellent mechanical properties, heat resistance, oil resistance and cold resistance as a combination of the features of silicone rubbers and acrylic rubbers.

Rubber composition

An acrylic rubber composition is proposed which is improved in respect of the extrusion-moldability as well as the surface slipperiness of the vulcanized article obtained therefrom. The composition comprises (a) an acrylic rubbery cooplymer which is a copolymer of a (meth)acrylic ester and a coolymerizable organosilicon compound having a silicon-bonded vinyl group in a molecule, (b) a reinforcing filler, (c) a powder of spherical particles having a specified average particle diameter and (d) an organic peroxide as a vulcanizing agent. The composition can be compounded further with a blowing agent to give a foamable rubber composition capable of being vulcanized into a spongy rubber body exhibiting excellent feeling on touch and slipperiness in contact with human skin to be useful, for example, as a material of cosmetic puffs.

A rubber composition based on a rubbery polymer and a silica-based reinforcing filler can be imparted with a greatly improved workability in roll milling and molding as well as in the mechanical properties of the vulcanizates prepared therefrom when the rubber composition is admixed with an acetylene alcohol or an alkylene-oxide adduct of acetylene alcohol presumably by virtue of the improvement in the dispersibility of the reinforcing filler in the rubbery matrix. The improvement obtained by the addition of the acetylene alcohol compound is not limited to the dispersibility of silica fillers but also to the dispersibility of carbon black when the rubbery polymer is an organopolysiloxane-modified acrylic polymer.

An excellently pleasant feeling of softness and elastic resilience can be imparted to a fabric material treated with the inventive fabric finishing agent which is an aqueous emulsion of a copolymer obtained by the emulsion polymerization, in an aqueous emulsion of an organopolysiloxane having radical-polymerizable groups, e.g., vinyl groups, or mercapto-substituted hydrocarbon groups, e.g., 3-mercaptopropyl groups, as the polymerization medium of an acrylic or methacrylic monomer, e.g., alkyl acrylates and methacrylates, in a specified amount relative to the amount of the organopolysiloxane. The acrylic or methacrylic monomer may be partly replaced with a polyfunctional monomer, e.g., acrylic and methacrylic acids, N-methylol acrylamide, glycidyl methacrylate, 2-hydroxyethyl methacrylate and the like, and/or a monomer of the third class, e.g., styrene and acrylonitrile. The emulsion may be further admixed with an organohydrogen polysiloxane as a crosslinking agent and a catalyst for the crosslinking reaction.

Silicone-based fabric finishing agent

Rubber vulcanizates having excellent oil resistance, heat resistance and cold resistance can be obtained from a rubbery copolymer which is a polymerization product of an acrylic monomer mixture of which the essential components are an organosiloxy-containing acrylate compound such as acryloxymethyl pentamethyl disiloxane and 3-acryloxypropyl pentamethyl disiloxane and an epoxy group- or halogen-containing monomer such as allyl glycidyl ether, glycidyl methacrylate and vinyl chloroacetate, optionally, with addition of an acrylate ester monomer such as ethyl acrylate, n-butyl acrylate and 2-methoxyethyl acrylate.

Monomeric composition and polymer therefrom

The inventive copolymer composition is satisfactorily curable or vulcanizable into, for example, a rubbery elastomer even by an organic peroxide contained therein as a crosslinking agent. The crosslinkable copolymer comprised therein is a polymer having, in a molecule, at least two monomeric units each having a vinyl-containing organosilicon pendant group represented by the general formula (Vi.sub.m R.sup.1.sub.n SiO).sub.a Vi.sub.b R.sup.2.sub.c Si--, in which Vi is a vinyl group, R.sup.1 is a hydrogen atom or a group selected from the class consisting of monovalent hydrocarbon groups free from aliphatic unsaturation, hydroxy group and hydrolyzable groups excepting halogen atoms, R.sup.2 is a hydrogen atom or a monovalent hydrocarbon group, m is 1, 2 or 3, n is zero, 1 or 2, a is 1, 2 or 3, b is zero, 1 or 2 and c is zero, 1 or 2 with the proviso that a+b=1, 2 or 3 and a+b+c=3. Such a copolymer can be prepared by the copolymerization of a first ordinary ethylenically unsaturated monomer and a second monomer having, simultaneously in a molecule, an ethylenically unsaturated linkage copolymerizable with the first monomer and the vinyl-containing organosilicon group of the above given formula.

Growing community of inventors

Fukui, Japan

Hiroyuki Ohata