热模压工艺参数对聚乳酸/竹纤维复合材料拉伸强度的影响

采用四元二次通用旋转组合设计试验方法,研究了聚乳酸与竹纤维混合比例(PLA/BF)、竹纤维粒径、热模压温度、热模压时间等4个因素对聚乳酸/竹纤维复合材料拉伸强度(TS)的影响,并采用差示扫描量热仪(DSC)对复合材料进行了热力学表征。结果表明,PLA/BF、热模压温度、热模压时间对复合材料的拉伸强度影响显著,热模压温度与热模压时间存在显著的交互效应。DSC分析显示,PLA/BF、竹纤维粒径、热模压温度/时间工艺参数影响材料中PLA的结晶度(Xm)。本试验条件下的聚乳酸/竹纤维复合材料热模压优化工艺参数为:PLA/BF为90/10,竹纤维过100目标准筛,热压温度160℃,热压时间25min,理论最大TS为66.40MPa。

Influence of Hot Press Molding Parameters on the Tensile Strength of Bamboo Fiber/PLA Composites

In order to develop environmental-friendly bamboo-plastic composites for industrial applications,the effects of poly(lactic acid)/bamboo fiber(PLA/BF) ratio,size of BF,molding temperature,and time on the tensile strength of PLA/BF composites were studied by using a second-order regression general rotation design.Thermal properties of the composites were characterized by differential scanning calorimeter(DSC).Results indicat that the PLA/BF ratio,molding temperature and molding time have significant effects on the tensile strength of the composites.Significant synergistic effect between molding temperature and molding time is observed.Crystallinity(Xm) of PLA in the composites is also influenced by PLA/BF ratio,size of BF,and temperature/time based on DSC analysis.Optimum hot pressing parameters under the experimental conditions are as follows: blend ratio of 90/10,size of BF using 100mesh standard sieve,molding temperature of 160℃,and molding time of 25min.Under this condition,the tensile strength of PLA/BF composite reaches 66.40MPa.