Prepn. of polyvinyl alcohol dispersion - contg. oil and calcium chloride, as additive for cement

摘要

Dispersion is prepd. by (a) mixing an aq. soln. of PVA with a dispersion obtd. by dispersing oil in water, with a surfactant, and (b) treating the mixt. with CaCl2 to form a uniform mixt. The dispersion is used as a water-repellent agent, adhesive for tiles, and anti-shrinkage agent for finishing compsns., coating compsns., and adhesives. The dispersion can be easily and cheaply produced on a large scale, with no pollution problems. It is odourless, harmless and non-inflammable. It can be stored for up to 1 year. The pourability of mortar does not decrease on standing. The water content of the cement may be 10-40% less than usual. Shrinkage and cracking of the cement are avoided. The cement has better resistance to water, weathering and alkali, and better physical properties. Bonding to reinforcing material is improved. Permanent rust protection is achieved.