Study and production of a one-part PU hydrophilic expansion sealant

Compared with water stop material of traditional hydrophilic expansion rubber strip,one-part PU hydrophilic expansion sealant possesses excellent construction properties.Refering to properties and application of abroad similar products and combining with our experience of study and production of PU sealants,using liquid polyether PU prepolymer as the basic material and adding several hydrophilic expansion materials,we developed a new one-part PU hydrophilic expansion sealant.The sealants reached the standard of foreign similar products and are suitable for construction joint waterproofing works,deformation joint assistant waterproofing and embedded part seepage-proofing for underground constructions,mountain and municipal tunnels,underground railroad and sewage treatment pool etc.The paper discussed the factors to influence hydrophilic expansion and the adjustment of sealant modulus,elasticity,hardness,tack free time and curing speed.