基于碱脲溶剂体系胶化作用的湿强纸的制备

Preparation of Wet-strength Paper Based on the Jellification of Alkali-urea System

中文关键词:  碱脲体系  胶化作用  慈竹  漂白硫酸盐浆  湿强纸

Key Words:alkali-urea system  Jellification action  Sinocalamus affinis  bleached kraft pulp  wet strength paper

中文摘要:

      在低温及中高浓度条件下，利用氢氧化钠 硫脲水溶液浸渍处理由漂白硫酸盐慈竹浆抄造的纸张，经冷冻及洗涤后制备湿强纸，通过单因素实验探究碱浓、浸渍时间、冷冻温度、冷冻时间和洗涤时间等因素对纸张强度性能的影响，并利用傅里叶变换红外光谱仪、X射线衍射仪、热重分析仪、核磁共振波谱仪和扫描电子显微镜表征处理前后纸张性能的变化情况。结果表明，在碱浓7%、浸渍时间3 s、冷冻温度-7℃、冷冻时间15 min、洗涤时间15 min的处理条件下，制得的湿强纸强度性能最好。与处理前原纸相比，在该条件下处理后纸张的干抗张指数提高了66%，干耐破指数提高了183%，湿抗张指数提高了321%，湿耐破指数提高了980%；同时处理后纸张中单根纤维的含量显著降低，且处理前后纸张纤维的官能团结构、无定形区和结晶区结构、热力学性能以及碳骨架结构均没有明显变化。

Abstract:

      In this work， the paper made from bleached bamboo （Sinocalamus affinis） kraft pulp was soaked in the NaOH urea aqueous solution， and then freezing and washing processes were applied to prepare wet strength paper. The effects of alkali concentration， soaking time， freezing temperature， freezing time， and washing time were evaluated by single factor experiments. The analyses of FT IR， XRD， TGA， NMR and SEM were applied to reveal the variations of the micro properties of the untreated and treated papers. The optimal preparation conditions were determined as the follows: alkali concentration of 7%， soaking time of 3 s， freezing temperature of -7℃， freezing time of 15 min， and washing time of 15 min. Compared with untreated paper， under the optimal conditions， the dry tensile index of the treated paper increased by 66%， the dry burst index increased by 183%， the wet tensile index increased by 320%， and the wet burst index increased by 980%. There were no significant variations of functional groups and the structures of amorphous or crystalline regions， however， the amount of individual fibers in the treated paper decreased significantly．