Preparation and Performance of Environmentally Friendly Polyurethane Waterproof Coating
A environmentally friendly waterborne polyurethane waterproof coating was successfully synthesized using water as the curing agent,diphenylmethane diisocyanate(MDI),polyether polyol(DL-2000D and MN-3050D),sulfonate grafted polyester diol(BY-3306)or the hydrophilic chain extender dimethylol butyric acid(DMBA)and filler as raw materials.The effects of ratio of polyether polyols,dosage of hydrophilic polyester diol,kinds and dosage of gas absorbent and dosage of water on the properties of the coatings were investigated.The results showed that the obtained waterproof coating(after curing with 15%water)had a tensile strength of 4.27 MPa,an elongation at break of 678%and a tear strength of 24.57 N/mm when the mass fraction of polyether triol in polyols mixture was 10%,mass fraction of BY-3306 in polyether glycol and BY-3306 mixture was 15%,or mass fraction of DMBA in the coatings was 0.8%,and dosage of Portland cement was 8%and the NCO content was 4.5%.
NETL
NSTL
万方数据
