硫酸预处理对PPTA短切纤维PFI打浆效果的影响

Influence of H_2SO_4 Pretreatment on PPTA Pulp Prepared by PFI Mill

使用硫酸对PPTA纤维进行预处理后再使用PFI磨打浆,通过对原纤及浆粕保水值、浆粕原纸抗张强度的测定以及纤维表观形貌观察(SEM)等表征手段,探讨了硫酸预处理对PPTA短切纤维打浆效果的影响。实验发现,经质量分数为80%的硫酸处理后,PPTA短切纤维表面有轻微的溶解现象,部分纤维主体上有小范围的浅层的纤维纵向劈裂现象;而经质量分数为85%的硫酸处理的PPTA短切纤维则纵向劈裂严重,小部分微纤已经裸露。由浆粕保水值及浆粕原纸紧度、抗张强度数据可知,经质量分数为80%和85%的硫酸处理后制备的浆粕原纤化程度较未处理的高。结合SEM照片发现,经预处理后磨浆的浆粕具有更充分的原纤化效果,主干纤维破坏严重。

PPTA fibers were pretreated with H2SO4 solution then beated by PFI mill. WRV and morphology （SEM） of PPTA fibers and PPTA pulp, density and tensile strength of the paper made of the PPTA pulp were studied in this paper. It was found from SEM that surface of PPTA fiber pretreated with 80% H2SO4 was slightly dissolved and there were some small cracks along the fibers. The PPTA fibers pretreated with 85% H2SO4 were splitted seriously along longitudinal direction and some fibrils were peeled from the trunks. The data of WRV of the PPTA pulp and density and tensile strength of the paper made of the PPTA pulp illustrated that the fibrillation degree of the PPTA pulp pretreated with 80% , 85% H2SO4 before beating were higher than that of PPTA pulp without any pretreatment. The observation of SEM indicated that the pulp, pretreated with H2SO4 solution before refining, had higher fibrillation degree and the fiber trunks were destroyed more seriously.