The Process Study Of Producing Cardboard Ring Crush Strengthening Agent By Resource Utilization Of Konjac Fly Powder

Konjac fly powder was a by-product of the production process which contained a lot of carbohydrates and trace elements. In 20 th century, the konjac fly powder was applied in fodder and desiccant with low ratio resulted in a waste of resources and environment pollution. The konjac fly powder was utilized more and more widely in food and pharmaceuticals industry with the advance of technology. Konjac fly powder was rich in starch, if this part of starch could be fully utilized, the fly powder could be effectively used, and the environment could be protected.Styrene-acrylic emulsion process was compounded by Styrene(St) and butyl acrylate(BA), which was simple easy to use and most widely applied in the paper and paper products processing industry. The cardboard crush strength and water resistance could be improved by styrene-acrylic emulsion. However, because of some shortcomings were in conventional styrene-acrylic emulsion, in recent year, the direction of graft copolymerization of cationic starch with styrene-acrylic emulsion was paid more attention.In this paper, under the action of enzyme, the konjac fly powder starch was prepared by powder, which was dealt with by different kind of ways to prepare starch solution. Graft starch solution with BA and St to prepare styrene-acrylic emulsion as surface sizing. The performance of emulsion was compared to determine the best synthesis methods and processes. The specific study is following:(1) Starch was prepared by konjac fly powder under the action of neutral protease, the effects of some factors were investigated such as substrate concentration, the amount of enzyme, hydrolysis temperature, reaction time and pH. The result showed that: when the substrate concentration was 10%, the amount of enzyme was 0.4%, the hydrolysis temperature was 45℃, reaction time was 1.5 h, pH was almost 7, then the content of starch could reach 82%.(2) Cationic starch was prepared by konjac starch under the action of α-amylase, which graft starch solution with BA and St, the effects of some factors were investigated such as the amount of α-amylase, the ratio between monomer and starch, the ratio between monomer, reaction time, the amount of initiator, the amount of AA. The result showed that: when the amount of α-amylase was 0.5%, the ratio between monomer and starch was 2:1, the ratio between monomer was 2:1, reaction temperature was 84℃, the amount of initiator was 3%, the amount of AA was 3%, the styrene-acrylic emulsion was the best, water resistant could reach 86.69 g/m2, rings crush strength could reach 8.21 kN/m.(3) Oxidized starch was prepared by konjac starch under the action of oxidant, which graft starch solution with BA and St, the effects of some factors were investigated such as the amount of oxidant, the ratio between monomer and starch, the ratio between monomer, reaction time, the amount of initiator, the amount of AA. The result showed that: when the amount of oxidant was 12%, the ratio between monomer and starch was 1:1, the ratio between monomer was 3:1, reaction temperature was 84℃, the amount of initiator was 3%, the amount of AA was 3%, the styrene-acrylic emulsion was the best, water resistant could reach 61.9 g/m2, rings crush strength could reach7.7 kN/m.(4) Cationic starch was prepared by konjac starch under the action of cationic etherification, which graft starch solution with BA and St, the effects of some factors were investigated such as the amount of cationic etherification, the ratio between monomer and starch, the ratio between monomer, reaction time, the amount of initiator, the amount of AA. The result showed that: when the amount of cationic etherification was 4%, the ratio between monomer and starch was 1:2, the ratio between monomer was 3:1, reaction temperature was 80℃, the amount of initiator was 3%, the amount of AA was 3%, the styrene-acrylic emulsion was the best, water resistant could reach30.09 g/m2, rings crush strength could reach 8.24kN/m.(5) The effect of graft copolymer of cationic starch was the best by these three kinds of graft copolymer of starch compared with commercial product in application performance. The performance of synthetic emulsion was the best which could promote the performance index of paperboard.