Isothermal and non-isothermal cold crystallization of tetrabenzofluorene (TBF) molecules
作者:A. A. Boopathi、Srinivasan Sampath、T. Narasimhaswamy
DOI:10.1039/c8nj06514d
日期:——
Design and synthesis of tetrabenzo[a,c,g,i]fluorene (TBF) derivatives are carried out to investigate the isothermal and non-isothermal cold crystallization (CC) behavior by various spectroscopic and analytical techniques. The unprecedented CC exhibited by TBF molecules is examined by systematic modification of alkyl chain length (C8–C18 even carbons) on both sides of the central phenyl ring. The CC
设计并合成了四苯并[ a,c,g,i ]芴(TBF)衍生物,以通过各种光谱和分析技术研究等温和非等温冷结晶(CC)行为。通过系统性地修饰中心苯环两侧的烷基链长(C8–C18甚至碳原子),检查了TBF分子表现出的空前的CC。通过热阶段偏振显微镜(HOPM),差示扫描量热法(DSC)和可变温度粉末X射线衍射(VT-PXRD)检查TBF衍生物的CC 。实验观察表明,随着烷基链长度的增加,C 10 H 21到C 16 H 33时,CC温度和活化能显着提高。非等温CC活化能使用Kissinger方程计算。通过采用DSC动力学参数,可以计算出TBF分子(TBFC10至TBFC18)的总活化能,范围为62.18–90.35 kJ mol -1。此外,绘制了在五个不同温度下等温CC动力学的Avrami因子,这表明随着温度的升高,CC时间会减少。