| 摘要 |
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 ): R2O-R1-O-(A1O)n-R3 (1 ) -(A2O)m-R4 (2) (wherein R1 is a C2-10 hydrocarbon group having an unsaturated bond; R2 is hydrogen or the formula (2); R3 and R4 are each independently hydrogen or a C1-8 alkyl group; A1O and A2O are one or more kinds of C2-4 oxyalkylene groups; and n and m are mean addition numbers of moles Of A1O and A2O, respectively, and 1 to 20).
|
