ANALYZING AV POLYPROPYLENGLYKOL SAOSOM TILLSATSAEMNE, SOM REDUCERAR KRYMPNINGENS STORLEK I DISPERSIONSPULVERSAMMANSAETTNINGAR AVSEDDA FOER BYGGMATERIALER

摘要

The subject of the invention is the use of polypropylene glycol as an additive reducing the amount of shrinkage in dispersion powder compositions for building materials, containing a) a base polymer from the group comprising the vinyl ester polymers, (meth)acrylate and/or styrene (co)polymers and vinyl chloride polymers and b) either b1) 2 to 20 % by weight, relative to the base polymer, of polyvinyl alcohol with a degree of hydrolysis of 85 to 94 mol % and a Höppler viscosity of from 2 to 40 mPa.s or b2) 2 to 20 % by weight, relative to the base polymer, of alkali metal salts or alkaline earth metal salts of phenolsulphonic acid/formaldehyde condensation products, and also c) 3 to 30 % by weight, relative to the total weight of polymeric constituents, of a fine antiblocking agent, characterised in that d) 1 to 20 % by weight, relative to the base polymer, of polypropylene glycol is present. The dispersion powder composition is particularly suitable for use in building materials, in particular dry mortars, which contain Portland cement as inorganic binder, and leads therein to lower shrinkage of the mortars.