Analysis On Fiber Morphology Characteristics And Micro Mechanical Properties Of Four Calamus Canes

Fiber, the longevous cell, is among the important constitutes of the microscopic structure of rattan. Its morphological characteristics and mechanical properties play a key role in the macroscopic mechanical properties and the utilization of rattan. Based on the previous studies, the morphological characteristics of fiber and microfibrillar angle were analyzed and assessed in this work using the fibers of C. simplicifolius Wei., C. nambariensis Becc. var. yingjiangensis S.J.Pei et S.Y.Chen., C. nambariensis Becc.var. xishuangbannaensis S.J.Pei et S.Y.Chen. and C. yunnanensis S.J.Pei et S.Y.Chen. as materials. In addition, the longitudinal tensile properties and cell wall hardness of fiber were tentatively determined by employing single fiber tensile technique and nanoindentation technology. The results were shown as follows:1.The morphological characteristics of fiber(1) From the roots, diameter, double wall thickness and wall to lumen ratio of fiber from C. simplicifolius assumed falling parabola trend, whereas the length, length-to-width ratio and lumen diameter did not vary significantly. The morphological characteristics of fiber showed significant difference from longitudinal height (0.01level). Averagely, C. simplicifolius was1449.82μm,10.66μm,137.4,7.80μm,3.68μm and1.76in fiber length, diameter, length-to-width ratio, double wall thickness, lumen diameter and wall to lumen ratio, individually.(2) Up the roots, C. nambariensis var. yingjiangensis was decreased in fiber diameter, double wall thickness and wall to lumen ratio, and was increased in length-to-width ratio. Moreover, the lumen diameter and length,did not vary significantly. The fiber diameter, length-to-width ratio, double wall thickness and lumen diameter showed significant difference from longitudinal height at0.01level, which did not occur to the length and wall to lumen ratio. Averagely, C. nambariensis var. yingjiangensis was1367.52μm,13.98μm,98.65,9.80μm,4.88μm and1.93in fiber length, diameter, length-to-width ratio, double wall thickness, lumen diameter and wall to lumen ratio, respectively.(3) The fiber length and length-to-width ratio of C. nambariensis var. xishuangbannaesis increased with the increase of longitudinal height, which was opposite to diameter, double wall thickness and wall to lumen ratio. Fiber diameter, length-to-width ratio, double wall thickness and wall to lumen ratio showed significant difference from longitudinal height at0.01level. Averagely, C. nambariensis var. xishuangbannaesis was1071.02μm,11.06μm,103.90,8.14μm,3.58μm and1.93in fiber length, diameter, length-to-width ratio, double wall thickness, lumen diameter and wall to lumen ratio, respectively.(4) From the roots, the fiber length and length-to-width ratio of C. yunnanensis var. yunnanensis assumed rise trend with the increase of height, on the contrary, the fibe diameter, double wall thickness and wall to lumen ratio reduced along with the increase of longitudinal height. Each morphological characteristic of C. yunnanensis var. yunnanensis significantly differed from longitudinal height at0.01level. Equally, the fiber length, diameter, length-to-width ratio, double wall thickness, lumen diameter and wall to lumen ratio of C. yunnanensis var. yunnanensis were1340.38μm,12.74μm,107.06,8.41μm,4.80μm and1.5, respectively. 2. The variation characteristics of microfibrillar angle of fiberAlong with the increase of longitudinal height, the microfibrillar angle of C. nambariensis var. yingjiangensis and C. yunnanensis var. yunnanensis increased, while that of C. simplicifolius and C. nambariensis var. xishuangbannaesis was higher in root and in top. In general, the absolute values of microfibrillar angle varied slightly. C. simplicifolius, C. nambariensis var. yingjiangensis, C. nambariensis var. xishuangbannaesis and C. yunnanensis var. yunnanensis were23.76°,23.04°,24.56°and25.88°in mean microfibrillar angle.3. The variation characteristics of longitudinal mechanical properties of fiberWith the increase of height, C. simplicifolius, C. nambariensis var. yingjiangensis, C. nambariensis var. xishuangbannaesis and C. yunnanensis var. yunnanensis varied significantly in tensile strength, longitudinal tensile modulus and elongation at break. The mean tensile strength of four rattans were0.60,0.54,0.57and0.46GPa respectively. The average longitudinal tensile modulus of the four were11.71,10.03,10.92and9.79GPa, individually. In addition, the elongation at break of the four rattans were19.68%,22.72%,19.7%and18.11%, respectively.4. The variation characteristics of longitudinal mechanical properties of cell wallThe thick layer hardness of secondary wall from C. simplicifolius, C. nambariensis var. yingjiangensisand C. nambariensis war. xishuangbannaesis were0.38,0.36and0.44GPa respectively, and the longitudinal modulus of elasticity of them were8.51,7.72and11.47GPa individually. C. yunnanensis var. yunnanensis was thinner in each layer of secondary wall and could not meet the test demand.