没食子酸/乙二胺共沉积聚酯纤维的制备及其成纸性能

Preparation of gallic acid/ethylenediamine co-deposited polyester fiber and its paper-forming properties

在碱性三羟甲基氨基甲烷(Tris)缓冲液中,将没食子酸与乙二胺通过迈克尔加成和席夫碱反应共沉积在聚酯短切纤维表面。测定了改性前后聚酯短切纤维的动态接触角,采用SEM观察了纤维的形貌,利用FTIR和XPS表征了纤维表面结构的变化,最后以改性前后聚酯短切纤维和阔叶木浆抄纸,测定了纸张的孔径分布变化和透气性,并测试了纸张物理性能。结果表明,经共沉积改性后的聚酯短切纤维表面存在大量羟基,纤维表面有氮元素生成,同时表面粗糙度提高,与未改性聚酯短切纤维相比,改性后聚酯短切纤维与去离子水的接触角降低了57.2°,显著改善了纤维的亲水性;与未改性纤维纸页相比,改性后纤维纸页抗张强度提高了35.2%,耐破指数提高了13.1%,透气度提高了11.1%,相同孔径范围内的孔径占比增加了23%~29%,纤维分散性明显提高。

Gallic acid and ethylenediamine were co-deposited on the surface of polyester chopped fibers by Michael addition and Schiff base reaction in tris(hydroxymethyl) aminomethane(Tris) buffer. The dynamic contact angles of polyester chopped fibers before and after modification were measured, and the morphology was observed by SEM. Changes in the surface structure of the fibers were characterized FTIR and XPS. Finally, the polyester chopped fibers before and after the modification and hardwood pulp were used to make paper. The changes of pore size distribution, air permeability and physical properties of the paper were tested. The results showed that there were a large number of hydroxyl groups on the surface of the polyester chopped fiber after co-deposition modification, nitrogen formed on the surface of the fiber, and the surface roughness of the fiber was improved. The water contact angle of the modified polyester was 57.2° lower than that of the unmodified polyester chopped fiber, which significantly improves the hydrophilicity of the fiber. Compared with those of the unmodified fiber paper, the tensile strength, bursting index and air permeability of the modified fiber paper were increased by 35.2%, 13.1% and 11.1%, respectively. Additionally, the pore diameter of the modified fiber paper was increased by 23%~29% within the same pore diameter range, and the fiber dispersion was significantly improved.