模拟胶片剥离法测定废纸浆中胶黏物表面黏性的研究

Measurement of the Surface Viscosity of Stickies in Waste Paper Pulp Based on the Simulation of Peeling Sticky Films

关键词:  胶黏物  表面黏性  剥离强度  沉积面积  滤水性能

Key Words:stickies  surface viscosity  peeling strength  deposition area  water drainage property

摘要:胶黏物在造纸过程中易黏附到烘缸和毛毯等部位,影响成纸质量。传统的胶黏物检测方法是通过测定胶黏物沉积面积和沉积数量评估胶黏物对造纸过程的影响,不能表征胶黏物表面黏性大小,因而不能客观表征胶黏物含量是否会对造纸过程产生危害。本实验提出一种新的通过模拟胶片拉开法测定剥离强度表征胶黏物表面黏性大小的检测方法。通过测定不同胶黏物模型物的表面黏性,分析了环境变化对胶黏物表面黏性的影响,以及胶黏物表面黏性对其沉积性能、浆料滤水性能的影响。实验结果表明，浆料在55℃下处理1 h,添加有聚丙烯酸酯的纸浆产生的胶黏物表面黏性最大,体系内无机盐的加入及温度的升高都会使胶黏物表面黏性增大,胶黏物的沉积性能增强；当聚丙烯酸酯产生的剥离强度由0.1607 N/mm上升到0.7676 N/mm时,胶黏物沉积面积最大由3997.3 mm²/m²上升到24226 mm²/m²,胶黏物数量最大由8760.4个/m²上升到96750个/m²,浆料的纸浆滤水性能变差,单位时间最大滤水量降低14 g。

Abstract:Stickies are easy to adhere onto dryers, belts and other parts in papermaking process, thus affecting paper product quality. Traditionally the effect of stickies on papermaking process is evaluated by testing its deposition area and amount. Those methods cannot characterize the surface viscosity of the stickies and its harm to papermaking process. A new method based on testing the peeling strength of two films coated with stickies was proposed in the study. The effect of system change on surface viscosity and the effect of surface viscosity on the deposition property and drainage property were analyzed by testing the surface viscosity of different stickies model substances. Results showed that the surface viscosity of the stickies in the pulp adding PA was the highest, the addition of inorganic salt and the temperature increase could increase the surface viscosity; the increase of the surface viscosity led to the increase of deposition. When the peeling strength of PA increased from 0.1607 N/mm to 0.7676 N/mm , the deposition area of stickies increased from 3997.3 mm²/ m² to 24226 mm²/ m², the number of stickies increased from 8760.4 per square meter to 96750 per square meter, the drainage property of pulp became worse and the maximum drainage weight decreased by 14 g in unit time.