| PU is an important class of polymer with （–NHCOO–）structural that have wideapplications in a number of different fields. However, the use of toxic isocyanate, which isresulted from an even more toxic predecessor, phosgene, might cause environmental andhuman health hazards. In order to overcome these drawbacks, people have began to developthe environment-friendly methods.By preparing via a nonisocyanate route, PU do not contain a high toxicity andmoisture sensitivity isocyanate, which are called NIPU. Nowdays, The isocyanate-freeprocess is based on the reaction of cyclocarbonates with amines, which forms the specialstructure that make up the weak bond in PU, so this materials have better chemicalresistance, hydrolysis resistance and permeability. What’s more, Environmental-friendlyand energy conservation will promote the development of waterborne resin technology tobecome the mainstream product in the related field. High performance andenvironmentally-friendly is an inevitable trend of NIPU, so the waterborne for NIPU hassignificant practical benefit.In this thesis, we prepared NIPU that based on the reaction between cyclic carbonateand primary amine. Two kinds of waterborne NIPU systems with CCMA and DAAM asfunctional monomers that were prepared by introducing hydrophilic groups to resins andemulsion polymerization techniques, then they reacted respectively with HAD and ADH forcross-linking reaction. FT-IR was used to confirm that cyclic carbonate side groups inpolymers reacted with primary amine groups to produce NIPU. Results showed that thewater-soluble system had better mechanical performance and poor water resistance (thedosage of DAAM was3%, MAA was1%); The emulsion system had excellent mechanicalperformance and water resistance (distribution proportion of CCMA was0.1/0.9, dosage ofemulsifier and initiator was0.5%and0.4%). So the emulsion NIPU had the better excellentproperties and was expected to be as matrix resin in coating field. |
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