Ca2+交联羧基化麦草秸秆化机浆的制备及性能研究

Study on Preparation and Properties of Ca2+-Crosslinked Carboxylated Wheat Straw Chemi-mechanical Pulp

中文关键词:  麦草秸秆化机浆  羧基化纤维  Ca²⁺交联  强度性能

Key Words:wheat straw chemi-mechanical pulp  carboxylated fibers  Ca²⁺ crosslinking  strength properties

中文摘要:

      本研究采用TEMPO氧化体系，转化麦草秸秆化机浆（SP）纤维素C6位上的羟基为羧基，制备羧基化麦草秸秆化机浆（CSP）；对CSP进行Ca²⁺交联，制备Ca²⁺交联羧基化麦草秸秆化机浆（CSP@Ca²⁺），探究其纸浆的物理强度性能。基于FT-IR、XPS等手段可以明显检测CSP 纤维的羰基/羧基官能团：羧基化1 h麦草秸秆化机浆纤维（CSP1）的羧酸含量为0.27 mmol/g，其Zeta电位从SP的-21.7 mV变化为-29.2 mV，这为Ca²⁺的交联提供作用位点。纸张物理强度结果表明，CSP1@Ca²⁺0.5的抗张指数、耐破指数和撕裂指数分别较SP提高154.4%、170.8%和12.9%。最终，CSP1@Ca²⁺0.5与SP配抄纸张（配抄比例为50∶50）的抗张指数、耐破指数和撕裂指数分别达27.1 N·m/g、2.28 kPa·m²/g和3.68 mN·m²/g，较SP分别提高83.4%、115.1%和8.3%。

Abstract:

      In this study， TEMPO oxidation was used to transform the hydroxyl group at C6 position of wheat straw pulp （SP） cellulose into carboxyl group to prepare carboxylated wheat straw pulp （CSP）. Ca²⁺ crosslinked carboxylated wheat straw pulp （CSP@Ca²⁺） was prepared by crosslinking CSP with Ca²⁺， and its strength properties were explored. The carboxyl/carbonyl groups of CSP fibers were determined by using FT-IR and XPS： the carboxyl group content of CSP carboxylated for 1 h （CSP1） was 0.27 mmol/g and its Zeta potential varied from -21.71 to -29.2 mV， which provided reactive sites for Ca²⁺ crosslinking. Compared with SP， tensile， burst， and tear indexes of CSP1@Ca²⁺0.5 improved by 154.4%， 170.8%， and 12.9%， respectively. Tensile， burst， and tear indexes of the mixed CSP@Ca²⁺0.5/SP （50∶50） paper were 27.1 N·m/g， 2.28 kPa·m²/g， and 3.68 mN·m²/g， increased by 83.4%， 115.1% and 8.3%， respectively， compared with SP.