Hydroxypropyl Starch are a starch-based additive designed for dry mortars in the building industry. These starch ethers can improve the performance and optimize the workability of dry mortar by modifying the thickness and rheology of varied dry mortars based on cement and gypsum.� Starch� ether� should be used in combination with cellulose derivatives. It can well perform in neutral and alkaline conditions, and it is compatible with other additives in gypsum or cement-based building materials.