搓丝处理后棉秆纤维束的形态特征及力学性能

Morphological and mechanical properties of cotton stalk fiber bundle through rub silk process

采用光学显微镜对经过搓丝工艺处理的棉秆皮部、木质部纤维束的形态特征进行观测分析,并对其力学性能采用纤维拉伸仪进行测定。研究结果表明:棉秆皮部纤维束长度为25.12 mm,宽度为201.9μm,长宽比为158.78,横截面面积均值为42 119.69μm2;棉秆木质部纤维束长度为13.57 mm,宽度为253.36μm,长宽比为76.88,横截面面积为69 249.16μm2。棉秆木质部纤维束的长度和长宽比均小于皮部,而宽度和横截面面积大于皮部。棉秆皮部纤维束抗拉强度为60.73 MPa,弹性模量为2.17 GPa,断裂伸长率为4.3;棉秆木质部纤维束拉伸强度为42.58 MPa,弹性模量为1.33 GPa,断裂伸长率为3.11,皮部纤维束的拉伸强度、弹性模量和断裂伸长率均大于木质部,柔韧性较好。棉秆皮部及木质部纤维束的力学性能低于其他植物,棉秆皮部纤维束的力学性能远低于皮部纤维细胞的力学性能。

The morphological structure, dimensions and mechanical properties of fiber bundle in cotton stalk epidermis and xylem were investigated using optical microscope and fiber tensile strength tester after they were disposed by rub silk process. The length, width, the radio and the cross-sectional areain cotton stalk epidermis were 25.12 mm, 201.9 μm, 158.78, and 42 119. 69 μm2 , respectively. The length, the width, the radio, and the cross-sectional areain cotton stalk xylem were 13.57 mm, 253.36 μm, 76.88, and 69 246. 16 laina, respectively. The length and radio of the fiber bun- dle in cotton stalk epidermis were lower than that in the xylem. The width and ross-sectional area in cotton stalk epider- mis were higher than the area in the xylem. The tensile stress, elastic modulus and elongation of fiber bundle in epider- mis were 60. 73 MPa, 2. 17 GPa, and 4. 3, and those in the xylem were 42. 58 MPa, 1.33 GPa, and 3.11, respective- ly. Fiber bundle in epidermis has a better flexibility because the tensile stress, elastic modulus and elongation in cotton stalk epidermis were higher than those in the xylem. The mechanical property of cotton stalk was poorer, compared with other plant fibers. The mechanical property of fiber bundle in epidemic was lower than single cotton stalk fiber. The re- suits provided the essential data for cotton stalk fiber used in plant fiber composites as the reinforced materials.