Performance and influencing factors of polythiourethane sealant
In this paper,5 different diisocyanates and 5 different catalysts were used to vulcanize polythioether system,and a new type of polythiourethane sealant material was produced.The composition of the material was analyzed by infrared spectroscopy,and the effects of different types of curing agents,catalysts,and polythioether raw adhesive on the mechanical and process properties of the material were compared.The research results showed that choosing IPDI and HMDI as the vulcanization systems for polythiourethane was relatively suitable.The catalytic efficiency of PC-41 and 1-methylimidazole was relatively moderate,and their catalytic efficiency for the reaction of isocyanates with water was not high,making them suitable as catalysts for the vulcanization of polysulfides.By characterizing the structure of polythiourethane sealant before and after vulcanization,it was demonstrated that the entire vulcanization reaction was complete.As the molecular weight of polythioether raw adhesive decreased,the tensile strength of the corresponding polythiourethane sealant increased,while the elongation at break decreased.Through the study of mechanical properties and oil resistance,it was found that the performance of polythiourethane sealant prepared by HMDI was superior.Compared with ordinary polythioether sealant,its mechanical properties had been improved while retaining oil resistance,and it had certain application value in the aerospace field.
万方数据
维普
