Mortar elastifying agent. Replaces all or part of the amount of mixing water in cement mortar mixes, e.g. tile adhesives (ISOMAT AK-9, ISOMAT AK-10, etc.) waterproofing cement-based slurries (AQUAMAT) and microcement coatings (DUROCRET-DECO), etc. Its use helps these products withstand normal movements caused by expansion and shrinkage of the substrate due to temperature variations and vibration.