蒸煮及打浆过程中剑麻浆聚合度和纤维长度的变化规律

Variations of Sisal Pulp Polymerization Degree and Fiber Lengthin in Cooking and Beating

本研究以剑麻为原料,探究了蒸煮和打浆过程对纸浆聚合度(DP)及纤维长度的影响。研究发现,在蒸煮过程中,随着用碱量增大、蒸煮温度升高,剑麻纸浆聚合度及纤维长度均呈减小趋势;随保温时间延长,二者呈现先增大后减小的趋势。在打浆过程中,纸浆聚合度及纤维长度随打浆度升高而减小。此外,讨论了不同蒸煮和打浆工艺下剑麻纸浆聚合度与纤维长度之间的关系。结果表明,纸浆聚合度与纤维长度在2种处理方式下均为正相关关系。在蒸煮过程中,纸浆聚合度及纤维长度都因纤维发生碱性降解而变化;在打浆过程中,微米/毫米尺度的纤维切断作用使纤维长度变短,但其对纸浆聚合度几乎没有影响,纳米尺度纤维的分丝帚化、吸水润胀及细纤维化等变化才会使纸浆聚合度显著下降。纸浆聚合度在2种处理过程中均随纤维长度减小呈现先缓慢后快速的下降趋势,原因与处理方式对纤维的作用机理相关。

In this paper,sisal was used as the raw material to discuss the effect on polymerization degree(DP)and fiber length of cooking and beating.During the cooking process,the results showed that both the DP and fiber length of sisal pulp decreased with the increase of the amount of alkali and cooking temperature,and showed an increasing following by decreasing trend with the extension time.During the beating process,the DP and fiber length decreased with the increase of the beating degree.In addition,the relationship between DP and fiber length of sisal pulp under different cooking and beating conditions was discussed.The results showed that there was a positive correlation between the DP and the fiber length under two treatments.In the cooking process,the DP of pulp and fiber length were changed due to the alkaline degradation of fiber.In the beating process,fiber sevring on micron/millimeter-scale resulted in shorter fiber lengths,but had almost no effect on the DP.The changes of nano-scale fibers such as fibrillation,water swelling and fine fiberization would significantly reduce the DP.The DP of pulp in two treatments showed a trend of first slowly and then rapidly decreasing as the fiber length reduced.The reasons were related to the mechanism of the treatments on the fiber.