Study on the Synthesis Technology of Low-Cost New Polyaminoamide Epichlorohydrin

In the present work, a new type of low-cost PAE wet-strength agent was prepared by the modification of urea based on the traditional agent. The first step was a polycondensation to form the polyamide prepolymer(PA), the molar ratio of diethylenetriamine(DETA) and adipic acid(AA) was 1.1:1, the reaction temperature was about 170℃, holding time was 200min, the viscosity of PA(50%) was 340 mPa·s. The second step was crosslinked reaction of epichlorohydrin(EPI) after the urea-modification, dosage of urea was 20% of PA(absolute dry PA), the reaction concentration was 30%, temperature was 60℃, epichlorohydrin was 40% of PA(absolute dry PA). The PAE obtained in this study was added to pulp and stirred 30s to form sheet, then it was cured in the oven at 101℃ about 30min, the tensile strength retention ratio is about 24.5%. Not only did the modified PAE have wet strength effect, but also it has property of water resistant. Compared with traditional PAE, the water resistance of modified PAE was well.