Supported carbonic acid esters useful as set accelerators and thixotropic agents in cement

摘要

Cementitious compositions are prepared using a dry, flowable admixture containing an ester of carbonic acid such as propylene carbonate and a solid, particulate support which is non-reactive toward the ester such as silica fume. Such admixtures accelerate the set and increase the thixotropy of unhardened mixtures containing hydraulic cement and water, yet can be readily handled and stored in stable form until ready to be used.