Research On The Synthesis Controlling Of High Performance PAE Resin And Its Enhancement

Among various kinds of paper wet strength agents, PAE resin had occupied the main position in paper wet strength agent market, because of its superior effect when it was used to improve paper strength. However, for the high wet strength paper, PAE resin was still unsatisfactory; meanwhile, the cost of PAE resin was high and the electropositivity was strong. In the case of high dosage, it was easy to make charge reversal, affect the distribution of PAE resin in fibers,and increased the difficulty of papermaking. According to the above problem, in order to prepare high performance PAE resin, the synthesis process of PAE resin was optimized in this paper. Combination with PAE resin enhancement mechanism, using carboxyl promoter to modify PAE resin, in order to further improve the enhancement performance of PAE resin. The results showed that:The polyamide intermediates has strong impact on the performance of PAE resin, the high viscosity intermediates were easy to prepare high wet strength properties agent. On the basis of the ratio of raw materials, the polyamide intermediate viscosity was affected by the temperature, holding time, the relationship between as follows:y=5.165z1+36.73z2-755.05,wherein y represented the viscosity of polyamide intermediate; z1 represented the reaction temperature; z2 represented reaction time.Alkylation of PAE resin had significant effects on the performance of itself,without affecting the storage time of PAE resin, increase the degree of alkylation of PAE resin could be beneficial to improve the wet strength performance. The dosage of epoxy chloropropane in alkylation process had strong influence on the performance of the PAE resin, when the dosage of epoxy chloropropane small or too large, could weak the self crosslinking ability of PAE resin, resulted in decline in the enhanced performance of the PAE resin, when EPI: PA(mole ratio)=1.4:1, the performance of PAE resin was best, and could get with the viscosity of 56.6 m Pa·s, the storage time of >90 days PAE resin; when the usage was 1.0%,compared with the commercially available PAE resin, the homemade PAE resincan be further improved dry tensile index of paper over 10%, wet strength over17%.The viscosity of Polyamide intermediate had obvious effect on synthesis control of PAE resin. the greater the viscosity of the polyamide intermediate, the shorter required time for the alkylation of synthetic PAE resin, which the strengthen performances was optimal; for the same viscosity polyamide intermediates, by adjusting the concentration of reactants or the p H value of the reaction system to control the reaction time of PAE resin alkylation. We found that the longer alkylation time, the better performance of the PAE resin,meanwhile, adjusted the amount of water of Polyamide system compared to adjust the p H to control the alkylation time, found the former had a strengthen performance.Adipic acid dosage could lower the cost of PAE resin, and improve the use efficiency of amine substance. However, increased the dosage of adipic acid could easily produce carboxyl end capping, results in the decrease of viscosity of polyamide intermediates. Using secondary adding of adipic acid could effectively guarantee the viscosity of polyamide intermediate, and added adipic acid 1 hour before the end of the amino acid reaction. In the same condition,compared with the conventional technology, secondary adding adipic acid could further improve the paper dry tensile index was about 6%, wet strength by about11%. Used maleic anhydride(MA) instead of part adipic acid could reduce the viscosity of polyamide intermediate, was not good to the performance.Carboxyl promoter can improve the performance of PAE resin.when the mixed ratio of 1# carboxyl promoter was 20%, the performance of the modification PAE resin was the best; under the above conditions, when the dosage of the modification PAE resin was 0.8%, which was benefit to the strength performanceof paper, pulp drainage and retention, and could improve the paper dry strength index about 17%, wet strength about 27%, folding about11%, tear index about 5%, which was more economical and efficient compared to the commercial PAE resin.