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Between neutral sizing agents, ASA has a lot of special merits, for example, the curing speed of ASA is very quick, and the addition of ASA is small. Because it is difficult to settle the hydrolysis ratio of ASA, AKD and neutral rosin size have been used in many local paper plants, but the market share of ASA is very small. It hasn’t been seen report, that ASA is applied to bagasse pulp. This topic quests mainly the sizing effect of ASA being used for sugar cane pulp. Through the SEM, ZETA potential and contact angle measuring, and many other scientific methods, particle size distribution and hydrolytic stability of ASA Emulsion are analyzed, as well as Water resistance and physical properties of paper.To hydrolytic stability of ASA emulsion, ASA is emulsified with the cationic starch in the text, we studied emulsify time, emulsify temperature, emulsify velocity, pH value, the ratio of starch and ASA and so on, to receive the best emulsifying conditions of ASA emulsion. In addition, we analyzed physical and chemistry performance of bleached bagasse pulp, such as the thin fibril contents, the contents of cellulose and quasi cellulose etc, to describe indirectly that bagasse pulp has some impact on ASA sizing effect. In addition, the additives addition, (such as starch、filler CPAMetc), pH value, beating degree are studied to receive the best sizing conditions.Cationic starch and acid starch had relatively satisfied effects on emulsifying ASA, and acid starch has better emulsification than Cationic starch. Through emulsifying ASA with Cationic starch with different degree of substitution, we know that Cationic starch with high degree of substitution is better than that with low degree of substitution. Furthermore, the ratio of starch and ASA increases, the size of ASA is smaller; when the ratio of starch and ASA is 3, the size of ASA is within 0.5-2μm, and suitable. optimizing further the other emulsifying conditions, we know that ASA emulsion has good stability and size distribution is between 0.5-2μm, when emulsify temperature is 30℃, pH value is between 4-5, emulsify time is 2 min.ASA is emulsified in the conditions that the ratio of starch and ASA is 3, emulsify temperature is 30℃, emulsify time is 2min, emulsify speed of ASA is 6000r/min. Bagasse Pulp has good sizing efficiency using ASA emulsion. When beating degree is about 40°SR, pH value of stock is 9, the addition of ASA is 0.2%, the addition of acid starch is 1.5%, the addition of PCC is 30%, the addition of CPAM is 0.015%, contact angle of paper is 140.0°, the sizing effect of ASA emulsion is good.
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