Kaneka Corporation

Matsumoto Yushi-seiyaku Co., Ltd.

The Yokohama Rubber Co., Ltd.

Bridgestone Corporation

Kenichi Kitano

Yoshiki Nakagawa

Masayuki Fujita

Masato Kusakabe

Nao Fujita

Toshiaki Masuda

Katsushi Miki

Takeshi Inohara

Takayuki Aoki

Ichiro Takahara

Shigeki Ono

Masanao Takeda

Katsuhiko Kimura

Naoki Furukawa

Shigeru Hagimori

Ikuo Yosejima

Akihisa Hirota

Kosuke Tanaka

Satoshi Kawanami

Yoshiaki Shirakabe

Sueo Kida

Koji Tanaka

Tomoki Hiiro

Naoki Kushida

Hiroyuki Teratani

Takamasa Kitamura

Sachiko Tokumura

Makio Mori

Shigeki Ito

Shigeki Ohno

Kyuno Seiji

Yoshitugu Sasaki

Hiroki Naito

Takeyoshi Fukuda

A method that produces heat-expandable microspheres includes the use of a shell of thermoplastic resin and a non-fluorine blowing agent encapsulated therein having a boiling point not higher than the softening point of the thermoplastic resin. The method includes a step of dispersing an oily mixture containing a polymerizable component, the blowing agent, and a polymerization initiator containing a peroxydicarbonate in an aqueous dispersing medium to polymerize the polymerizable component contained in the oily mixture. The resultant heat-expandable microspheres have a shell which is less apt to become thinner than its theoretical value, contain minimum amount of resin particle inside their shell, and have excellent heat-expanding performance.

Heat-expandable microspheres and a process for producing the same

A tread rubber is made of a rubber composition containing 100 pbw of a diene rubber, 30 to 100 pbw of a reinforcing filler including at least 10 pbw of silica, and 1 to 20 pbw of microcapsules each encapsulating a heat-expandable substance. A sulfur-containing silane coupling agent is mixed in the rubber composition in an amount of 3 to 15 wt. % based on the weight of the silica. A shell material of each microcapsule is made of a thermoplastic resin which essentially contains a nitrile monomer. A vapor pressure of the heat-expandable substance is 1.4 to 3.0 MPa at 150&#xb0; C. An average diameter of the microcapsules is 20 to 30 &#x3bc;m before vulcanization of the rubber composition. An average diameter of the microcapsules expanded due to the vulcanization is 40 to 80 &#x3bc;m. The tread rubber has a proportion of a cell-occupying area of 5 to 30%.

Pneumatic tire

The present invention provides heat-expanded microspheres having high packing efficiency, and a production method thereof. The heat-expanded microspheres are produced by expanding heat-expandable microspheres, which comprise shell of thermoplastic resin and a blowing agent encapsulated therein having a boiling point not higher than the softening point of the thermoplastic resin and have an average particle size from 1 to 100 micrometer, at a temperature not lower than their expansion initiating temperature, and the heat-expanded microspheres result in a void fraction not higher than 0.70.

Thermally expanded microspheres and a process for producing the same

A method that heat-expandable microspheres includes the use of a shell of thermoplastic resin and a non-fluorine blowing agent encapsulated therein having a boiling point not higher than the softening point of the thermoplastic resin. The method includes, a step of dispersing an oily mixture containing a polymerizable component, the blowing agent, and a polymerization initiator containing a peroxydicarbonate in an aqueous dispersing medium to polymerize the polymerizable component contained in the oily mixture. The resultant heat-expandable microsphres have a shell which is less apt to become thinner than its theoretical value, contain minimum amount of resin particle inside their shell, and have excellent heat-expanding performance.

Heat-expandable microspheres include a shell of thermoplastic resin and a blowing agent encapsulated therein having a boiling point not higher than the softening point of the thermoplastic resin, have a maximum expanding ratio not lower than 50 times, and are thermally expanded into hollow particulates having a repeated-compression durability not lower than 75 percent. The method of producing the heat-expandable microspheres includes the steps of dispersing an oily mixture containing a polymerizable component and the blowing agent in an aqueous dispersing medium containing a specific water-soluble compound and polymerizing the polymerizable component contained in the oily mixture.

Heat-expandable microspheres, method for producing the same, and application thereof

Heat-expandable microspheres include a shell of thermoplastic resin and core material encapsulated in the shell. The core material include a blowing agent having a boiling point not higher than the softening point of the thermoplastic resin and a gas migration inhibitor having a boiling point higher than the softening point of the thermoplastic resin. The ratio of the gas migration inhibitor to the core material is at least 1 weight percent and below 30 weight percent. The average particle size of the heat-expandable microspheres ranges from 1 to 100 micrometers.

Heat-expandable microspheres, process for producing the same, and application thereof

A production method for heat-expandable microspheres, which have high expanding ratio and are thermally expanded into hollow particulates having excellent repeated-compression durability, and application thereof are provided. The method produces heat-expandable microspheres a shell of thermoplastic resin and a blowing agent being encapsulated therein and having a boiling point not higher than the softening point of the thermoplastic resin.

Method for producing heat-expandable microspheres and application thereof

Heat-expanded microspheres having high packing efficiency are produced by expanding heat-expandable microspheres, which include a shell of thermoplastic resin and a blowing agent encapsulated therein having a boiling point not higher than the softening point of the thermoplastic resin and have an average particle size from 1 to 100 micrometer, at a temperature not lower than their expansion initiating temperature, and the heat-expanded microspheres result in a void fraction not higher than 0.70.

A rubber composition for a tire containing (i) 100 parts by weight of a diene-based rubber and (ii) 0.5 to 25 parts by weight of a heat-expandable microcapsule including a shell, and a substance capable of vaporizing or expanding under heating to thereby generate a gas and a nonpolar oil, both encapsulated in the shell,

Rubber composition for tire

The present invention provides: a process for preparing a vinyl polymer containing a halogen in an amount of 1,000 mg or less per kilogram, in which a vinyl polymer containing the halogen produced by atom transfer radical polymerization of a vinyl monomer is heated at a temperature in the range of 140 to 250&#xb0; C. to dehalogenate the vinyl polymer; a vinyl polymer obtained by the process; and a hydrosilylation-reactive curable composition containing the vinyl polymer.

Process for producing vinyl polymer, vinyl polymer, and curable composition

Thermo-expansive microcapsule comprising: a polymeric shell produced by polymerizing 15 to 75 weight % of a nitrile monomer, 10 to 65 weight % of a monomer having a carboxyl group, 0.1 to 20 weight % of a monomer having an amide group and 0.1 to 20 weight % of a monomer having a cyclic structure in its side chain; and a blowing agent encapsulated in the polymeric shell.

Thermo-expansive microcapsule, production process of expanded product and expanded product thereof

A method for producing a (meth)acrylic polymer having crosslinkable silyl groups at the termini, comprising a step of adding a hydrosilane compound having a crosslinkable silyl group to an alkenyl-terminated (meth)acrylic polymer (A), which is prepared by atom transfer radical polymerization, in the presence of a platinum hydrosilylation catalyst. The amount of the platinum hydrosilylation catalyst is 0.1 to 10 mg on a platinum metal basis per kilogram of the alkenyl-terminated (meth)acrylic polymer (A). An object of the invention is to provide a method for producing a (meth)acrylic polymer having terminal crosslinkable silyl.

Process for producing (meth)acrylic polymer terminated by crosslinkable silyl group

The present invention is concerned with a vinyl polymer having at least one group of the general formula (1) permolecule at the molecular chain terminus.&#x2014;Z&#x2014;R&#x2014;CR&#x2550;CRR&#x2003;&#x2003;(1)wherein Z represents an oxygen atom, a sulfur atom, a group of the formula NR', R&#x2032; represents a univalent hydrocarbon group containing 1 to 20 carbon atoms, or a bivalent organic group containing 1 to 20 carbon atoms, and R represents a carbonyl group, a direct bond or a bivalent organic group containing 1 to 20 carbon atoms; Rand Rare the same or different and each represents a hydrogen atom or a univalent organic group containing 1 to 20 carbon atoms, and Rrepresents an organic group containing 1 to 20 carbon atoms. The present invention is further concerned with a curable composition comprising the above vinyl polymer.

Polymers and curable compositions

This invention provides a production method of a vinyl polymer having a functional group at a molecular chain terminus which comprises adding a compound (I) having a functional group and an internal alkenyl group or conjugated polyene compound (II) in the living radical polymerization of a radical-polymerizable vinyl monomer. The present invention relates to a vinyl polymer having a functional group at a molecular terminus, a production method of the same and a curable composition containing said polymer.

Growing community of inventors

Kobe, Japan

Kenichi Kitano