由刚性链和柔性链组成的刚柔嵌段共聚物具有优异的性能,在各行各业得到广泛应用。利用分子动力学方法探究了这类聚合物中刚性强度、含量、刚性段分布对材料力学强度和生热性能的影响。研究发现,刚性强度和刚性嵌段含量增加均会导致材料力学强度提高和生热性能变差,但当刚性嵌段含量一定时,通过调控刚性段嵌段分布可以获得力学性能优异、滞后生热损失低的材料。在此基础上,探究了支化和交联的影响,研究结果表明,分子链支化和柔性嵌段交联能够改善材料力学性能。
Rigid-flexible block copolymers composed of rigid chains and flexible chains have excellent properties and are widely used in various industries.The effects of the rigid strength,content and distribution of rigid segments on the mechanical strength and thermal performance of these copolymers were investigated by molecular dynamics.The study found that the increase of rigid strength and rigid block content leaded to the improvement of mechanical strength and the deterioration of thermal performance.When the content of rigid block was constant,the material with excellent mechanical properties and low hysteretic heat generation loss could be obtained by adjusting the distribution of rigid block.On this basis,the effects of branching and cross-linking were explored,and the results showed that molecular chain branching and flexible block cross-linking could improve the mechanical properties of the materials.
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基金资助
国家自然科学基金资助项目(U21A2094);安徽高校协同创新项目(GXXT-2019-017);安徽省自然科学基金(2108085ME153)
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