Evaluation Of Two Cationic Surface Sizing Agents Applied To Corrugated Medium

In recent years, development and production of moisture-proof packaging paper haveobtained widespread attention from paper industry at home and abroad. When waste paper isused as the main raw material to produce moisture-proof packaging paper, some problemswith the quality of the products occur. Application of surface sizing could solve the problemscaused by repeated use of secondary fiber and improve quality of the products. As a result,surface sizing technology is extremely important for sustainable development of paperindustry and development of recycling economy.A new kind of cationic complex formulation surface sizing agent synthesized by AKDand paraffin is developed and the process for the synthesis of this cationic surface sizing agentis provided. The purpose of the research is to shorten the aging time and enhance humidityresistance of the paper with surface sizing. The results showed that preparation process of thiskind of AKD/paraffin cationic complex surface sizing agent is simple, low cost and suitablefor large-scale production in the factory.Comparison of the physical performance of this AKD/paraffin surface sizing agent andthe cationic SAE surface sizing agent indicated that this AKD/paraffin surface sizing agent ismore suitable for surface sizing. SEM analysis indicated that fibers in the corrugated paperafter surface sizing by these two kinds of surface sizing agent bound more closely and a layerof continuous film was formed on the surface of the paper. Film-forming property of the paperwith surface sizing by cationic SAE surface sizing agent was slightly better than the AKD/paraffin surface sizing agent. Considering the cost of production, when2Kg/t of the cationiccomplex surface sizing agent and40Kg/t of the starch were used for surface sizing,satisfactory sizing efficiency was achieved, which is cost-effective when compared withapplication of other surface sizing agents. The production cost was reduced by4RMB foreach ton of paper produced by using AKD/paraffin sizing agent, compared with cationic SAEsurface sizing agent, indicating the practical application feasibility of such a cationic complexsizing agent.The practical application efficiency of the two kinds of surface sizing agent in factorywas also discussed in the paper. The water resistance performance of these two surface sizingagents was the same based on the results of machine test in two factories. However, strengthproperties of the corrugated paper after surface sizing by AKD/paraffin cationic complexsurface sizing agent were better than the paper after surface sizing by cationic SAE surfacesizing agent. Especially, the folding strength improved by35.9%and tearing strength improved by12.1%after surface sizing by AKD/paraffin cationic complex surface sizingagent. On the other hand, results showed that the moisture regain rate of the paper aftersurface sizing by AKD/paraffin cationic complex surface sizing agent was32.61%, whichwas lower than the moisture regain rate of34.74%after surface sizing by and cationic SAEsurface sizing agent.In summary, the cationic complex formulation surface sizing agent which is synthesizedby AKD and paraffin with simple and low cost process can improve the water resistanceperformance and strength properties of the paper and is feasible for use as a new surfacesizing agent of paper. Practical application of this surface sizing agent in paper industry is infavor of developing new paper chemicals, realizing high value utilization of resources andenvironmental protection and energy saving.