Nippon Shokubai Co., Ltd.

Koichiro Nagare

Tsuyoshi Hirata

Tsutomu Yuasa

Katsuhisa Shiote

Toru Uno

Syogo Iwai

Yoshiyuki Onda

Shogo Iwai

Hideyuki Tahara

Yuichi Kita

Hirokatsu Kawakami

Hideaki Nagano

Keiji Yurugi

Koichi Nakagawa

Masaya Yamamoto

Mitsuaki Makino

Minoru Miyagawa

Masato Nishiue

Hisamoto Kawano

It is an object of the present invention to provide a production method of a dehydration reaction product by which the occurrence of troubles in the production step or the degradation in performance characteristics or quality of various chemical products can be suppressed to a satisfactory extent. A production method of a dehydration reaction product

Production process for product of dehydration reaction and apparatus used for the production

It is an object of the present invention to provide a storing and/or transferring method of polyalkylene glycol monomers by which the gel-like matter formation and/or decomposition reaction can be satisfactorily inhibited and, as a result, troubles can be prevented from occurring in the production process and the performance characteristics or quality of various chemical products can be satisfactorily prevented from being deteriorated. A storing and/or transferring method of a polyalkylene glycol monomer which comprises storing and/or transferring a polyalkylene glycol monomer in the form of an aqueous solution.

Storage and/or transportation method of polyalkylene glycol monomers

A storing and/or transferring method of an alkoxy(poly)alkylene glycol-containing material for cement additive polymer

Storage and/or transportation method of alkoxy (poly) alkylene glycol-containing materials

Method for producing chemical reactive substance and polycarboxylic acid produced thereby

Cement additive

The present invention provides a method for producing a cement dispersant having high percentage in water reduction rate and appropriate air-entraining property. This method for producing a polycarboxylic acid for a cement dispersant is characterized in that alkylene oxide is added at a specific temperature range.

Method for producing polycarboxylic acid for cement dispersant and cement composition

Anti-shrinkage agent for hydraulic material

The present invention provides a method for producing a cement dispersant having high percentage in water reduction-rate and appropriate air-entraining property. This method for producing a polycarboxylic acid for a cement dispersant is characterized in that alkylene oxide is added at a specific temperature range.

Cement dispersant, method for producing polycarboxylic acid for cement dispersant and cement composition

The invention provides: a cement admixture which has excellent cement dispersibility and can afford high slump retainability; and a cement composition which has excellent cement dispersibility and high slump retainability. The cement admixture comprises a polycarboxylic acid as an effective component, wherein the polycarboxylic acid is obtained by a process including the steps of: charging 'a' parts by weight of a polyalkylene glycol (A) and 'b' parts by weight of a (meth)acrylic acid monomer (B) into a reactor in the range of {(a/n.sup.1/2)/b}.times.100.ltoreq.200, wherein n is an average molar number of the added oxyalkylene groups in the polyalkylene glycol (A) and is a number of 1 to 300; carrying out an esterification reaction of the resultant mixture in the reactor, thus obtaining a polyalkylene glycol (meth)acrylate (C); and copolymerizing the resultant polyalkylene glycol (meth)acrylate (C) and the (meth)acrylic acid monomer (B), thus obtaining the polycarboxylic acid.

Cement admixture and cement composition

A method for the dispersion of cement, which comprises incorporating in a cement composition consisting at least of cement and water a cement dispersing agent formed of a polymer obtained by polymerizing a monomer component containing an alkoxy polyalkylene glycol mono(meth)acrylic ester monomer produced by the interesterification of an alkoxy polyalkylene glycol and a (meth)acrylic ester. A cement composition comprising the cement dispersing agent, cement and water.

Method for dispersion of cement

A cement composition excelling in the slump retaining property which comprises at least cement admixture comprising as a main ingredient thereof (I) a copolymer (A) of short-chain polyalkylene glycol (meth)acrylate (a), a long-chain polyalkylene glycol (meth)acrylate (b), a carboxylic acid monomer (c), and a monomer copolymerizable with the monomers mentioned above or a salt of the copolymer (B), (II) a copolymer (A.sub.1) of the monomers (a), (c), and (d) mentioned above or a salt thereof, (III) a mixture of a copolymer (A.sub.1) of the monomers (a), (c), and (d) mentioned above or a salt (B.sub.1) of thereof with a known cement admixture, or (IV) a polycarboxylic acid based polymer (A.sub.3) manifesting to a calcium sulfoaluminate based expansive additive an adsorption ratio of not less than 90% in 5 minutes at room temperature when added in an amount of 0.1% by weight as solids or a salt (B.sub.3) thereof, or (V) a mixture of said polycarboxylic acid polymer with a known cement dispersant; cement; and water.

Cement composition

The present invention provides a cement additive its production process and cement composition achieving excellent slump loss prevention capability. As a cement additive, there can be a copolymer (A-1) comprising an unsaturated polyalkylene glycol ether-based monomer (I), maleic acid-based monomer (II) and other monomer (III) copolymerizable with these monomers, the monomer (I)/monomer (II)/monomer (III) weight ratio being 50-99/50-1/0-49 and the weight average molecular weight of the copolymer (A) being 10,000 to 100,000 in terms of polyethylene glycol measured by gel permeation chromatography, or a copolymer (A) with an antifoaming agent (B), wherein the copolymer (A) comprises polyalkylene glycol ether-based units and dicarboxylic acid-based units as repeating units.

Cement additive, its production process and use

A novel acrylic ester which is represented by general formula (2) ##STR1## wherein R.sub.1 and R.sub.2 independently represent a hydrogen atom or an organic residue, R.sub.3 represents an organic residue, n is a positive number among 1 to 3, and m is a positive number among 1 to 100 and which is applicable to various uses, is obtained by reacting an acrylic ester of general formula (3) ##STR2## wherein R.sub.1 represents a hydrogen atom or an organic residue, and R.sub.3 represents an organic residue, with a cyclic ether compound of general formula (4) ##STR3## wherein R.sub.2 represents a hydrogen atom or an organic residue, and n is a positive number among 1 to 3. Moreover, a novel acrylic acid derivative whose use is even wider is obtained by hydrolyzing the acrylic acid derivative.

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Kawasaki, Japan

Koichiro Nagare