Other

Construction Research & Technology Gmbh

Takumi Sugamata

Tomomi Sugiyama

Mitsuo Kinoshita

Shinji Tamaki

Minoru Yaguchi

Hiroshi Nakanishi

Raita Iwata

Masaki Ishimori

To provide shrinkage reducing agents which render excellent shrinkage reducing effect and frost-thaw resistance to cement compositions such as mortar and concrete without entraining excessive air, and exhibit excellent solution stability. The shrinkage reducing agent comprises a (poly)alkylene compound having an unsaturated bond represented by the formula (1):RO&#x2014;R&#x2014;O-(AO)&#x2014;R&#x2003;&#x2003;(1)-(AO)&#x2014;R&#x2003;&#x2003;(2)(wherein Ris a Chydrocarbon group having an unsaturated bond; Ris hydrogen or the formula (2); Rand Rare each independently hydrogen or a Calkyl group; AO and AO are one or more kinds of Coxyalkylene groups; and n and m are mean addition numbers of moles of AO and AO, respectively, and 1 to 20).

Shrinkage reducing agent

A multi-functional cement dispersant contains a graft copolymer obtained by a graft reaction of one or more selected from polyoxyalkylene monoalkylester, polyoxyalkylene monoalkylether and polypropyleneglycol of specified kinds to a copolymer obtained by radical polymerization of a mixture of radical polymerizable monomers containing maleic anhydride and monomers of a specified kind at a specified ratio. Hydraulic cement compositions produced with such a multi-functional cement dispersant have a superior fluidity with reduced loss over time and hardened objects produced from such a composition exhibit a superior early strength and have a low dry shrinkage and a high resistance against freezing and thawing.

Multi-functional cement dispersants and hydraulic cement compositions

Growing community of inventors

Chigasaki, Japan

Takumi Sugamata