不同方法制备的淀粉基生物胶乳的性能研究

Study on the Properties of Starch Based Bio-latex Prepared with Different Methods

关键词:  淀粉基生物胶乳  涂料性能  涂布纸性能  涂层微观结构

Key Words:starch based bio-latex  coating color properties  coated paper performance  coating layer microstructure

摘要:研究了化学改性法生物胶乳（自制）、机械研磨法生物胶乳（自制）和机械挤出法生物胶乳（商品）3种淀粉基生物胶乳的物理性能及其对涂料性能和涂布纸性能的影响。结果表明,化学法生物胶乳不具有微粒形态；机械研磨法生物胶乳的中位径为0.161 μm、粒度分布宽,溶解性和润胀性较高；挤出法生物胶乳粒度分布均匀,中位粒径为0.184 μm。化学改性法生物胶乳的涂料低剪切黏度较低、保水性能较差,机械研磨法生物胶乳涂料的黏度最高、保水性能最好；剪切速率超过100 s^-1后,3种涂料的黏度趋于接近。生物胶乳会使涂布纸的孔隙率下降、亮度提高；化学改性法生物胶乳可达到甚至改进涂布纸的各项性能；挤出法生物胶乳可获得较好的涂布纸性能；机械研磨法生物胶乳对涂布纸的光泽度和平滑度有微小不利影响，有待进一步改进。

Abstract:Physical properties of various starch based bio-latexes prepared with chemical modified method, mechanical grinding method and extrusion methods, and their effects on coating color and coated paper performance were analyzed in this article. The results indicated that the commercial extruded bio-latex was evenly size distributed spheres with median diameter of 0.184 μm, while the mechanical ground bio-latex had median diameter of 0.161 μm with much wider particle size distribution, which had a relatively high solubility and swellability. Chemical modified bio-latex caused lower coatings viscosity and poor water retention capacity, whereas mechanical ground bio-latex led to higher coatings viscosity and the best water retention ability. Coating colors containing different bio-latexes tended to show similar viscosity as shear rate exceeded 100 s^-1. Coated paper porosity decreased as a result of the addition of bio-latex, whereas brightness was enhanced significantly. Both the chemical modified bio-latex and the extruded one could lead to preferable paper properties, while self-prepared mechanical ground bio-latex had a little negative impact on the property of the coated paper.