摘要
通过改进有机溶剂辅助插层(OAIC)方法制备了具有单层结构和优异的有机溶剂分散性能的二维过渡金属碳/氮化物(MXene)纳米片层,采用溶解-分散结合溶液浇铸方法制备了不同MXene含量的聚乳酸(PLA)复合薄膜并进行了退火处理,研究了热处理对MXene/PLA复合材料结构和性能的影响。结果表明,HCl-LiF可以刻蚀掉Ti3AlC2中的Al,制备出能够均匀、稳定地分散在有机溶剂中的单层MXene纳米片层。热处理不会改变PLA的结晶结构。热处理过程增加了PLA大分子链的活性,减小了MXene片层间距,使MXene的取向更一致。MXene含量是影响PLA复合材料T_(cc)和结晶速率的关键因素,3.5 phr是MXene用于PLA共混改性的浓度阈值。热处理降低了PLA的T_(cc),提高了其结晶速率,使PLA出现结晶细化和热收缩。MXene3.5PLA的拉伸强度增加至热处理前的9.2倍,断裂方式转变为脆性断裂。
Two-dimensional transition metal carbon/nitride(MXene)nanosheets with single layer structure and excellent organic solvent dispersibility were prepared by updated organic solvent-assisted intercalation(OAIC)method.Polylactide(PLA)composite films with different MXene content were prepared by solution casting method.Then,the effects of annealing on the structure and properties of the MXene/PLA composites were investigated.Results show that annealing does not change the spherulitic structure of PLA.The annealing process decreases the interplanar crystal spacing of MXene and makes its arrangement more consistent by increasing the mobility of macromolecule chains of PLA.The content of MXene is the key factor that determines both T_(cc)and crystallization rate of the resultant PLA composites.When MXene was used to modify PLA,3.5 phr is its threshold concentration.Furthermore,annealing improves the crystallization rate of PLA and refines its grains via reducing its cold crystallization temperature,and enables the composite crystallization thinning phenomenon.The tensile strength of the annealed MXene3.5PLA is enhanced by 9.2 folds,compared with its unannealed counterpart.Also,its fracture mode changes from ductile fracture before annealing to brittle mode.
作者
戚新宇
宗艺
强涛
Xinyu Qi;Yi Zong;Tao Qiang(School of Materials Science and Chemical Engineering,Xi'an Technological University,Xi'an 710021,China)
出处
《高分子材料科学与工程》
北大核心
2025年第6期33-39,共7页
Polymer Materials Science & Engineering
基金
陕西省教育厅服务地方专项计划项目(22JC038)。
