青岛科技大学  English 
张建明
赞  

教师拼音名称:zhangjianming

手机版

访问量:

最后更新时间:..

Small- and wide-angle X-ray scattering study on ????-to-?? transition of Poly(L-lactide acid) crystals

关键字:X ray scattering;Annealing - Crystallization - Intelligent systems - Isothermal annealing - Melting - Monte Carlo methods - Recrystallization (metallurgy)

摘要:We employed time-resolved simultaneous small- and wide-angle X-ray scattering (SAXS/WAXS) measurements in combination with a temperature-jump (T-jump) installment to investigate &alpha;&prime;-to-&alpha; transition in poly(L-lactide acid) (PLLA) crystals during isothermal annealing at a high temperature. Upon heating in a short period (ca. 10s) to the annealing temperature 150 &deg;C, the melting within the pre-existing &alpha;&prime;-crystal domains before recrystallization into neighboring &alpha;-crystals was observed, appearing as discontinuous first order &alpha;&prime;-to-&alpha; transition, which confirms the melting-recrystallization mechanism co-existing with continuous crystal perfection. Furthermore, during &alpha;&prime;-to-&alpha; transition the loosely packed 10/3 helices of &alpha;&prime;-crystals reorganized into the stable &alpha;-crystals by extending the lateral crystal sizes rather than the lamellar thickness. Based on our structural characterization, the microscopic mechanism of &alpha;&prime;-to-&alpha; transition in PLLA crystals was proposed and approved by dynamic Monte Carlo simulations.<br/> &copy; 2019 Elsevier Ltd

卷号:167

是否译文:

崂山校区 - 山东省青岛市松岭路99号   
四方校区 - 山东省青岛市郑州路53号   
中德国际合作区(中德校区) - 山东省青岛市西海岸新区团结路3698号
高密校区 - 山东省高密市杏坛西街1号   
济南校区 - 山东省济南市文化东路80号©2015 青岛科技大学    
管理员邮箱:master@qust.edu.cn