热台偏光法观察玻纤拔除致聚丙烯不同结晶形态的实验教学设计

Experimental Course Design for Observing Different Crystallization Forms of Polypropylene Caused by Glass Fiber Extraction Using Microscopy with Hot Stage

  • 摘要: 通过热台控温,观察预埋入的玻璃纤维诱发聚丙烯等温结晶生长出横晶结构的现象;然后在聚丙烯熔体中拔除预埋入的玻璃纤维,观察剪切致晶诱发的横晶及其生长过程;最后通过纤维拔除后的退火实验设计,验证聚合物分子链结晶过程的松弛特性。对传统偏光显微镜观察聚丙烯球晶形态的高分子物理实验进行了全新设计,加深了学生对球晶和横晶结构的认知以及对异相成核、剪切致晶过程的理解。实验具有创新性和合理性,且操作简便,教学效果显著。

     

    Abstract: The phenomenon of polypropylene isothermal crystallization with transcrystallinity structure induced by pre-embedded glass fiber is observed by controlling the temperature on a hot stage. After that, the pre-embedded glass fiber is extracted from the polypropylene melt, and the transcrystallinity induced by shearing and its growth process is observed. Finally, the relaxation characteristics of molecular chain during crystallization process are verified by the design of annealing experiment after fiber extraction. This experiment has a brand-new design for the high polymer physics experiment of observing the morphology of polypropylene spherulites with the traditional micropolariscope, which deepens the students’ understanding of spherulite and transcrystallinity structures under heterogeneous nucleation and shearing-induced crystallization. The innovative and reasonable experiment is easy to operate and has remarkable teaching effect.

     

/

返回文章
返回