Polymorphism and Structural Transition around 54 掳C in Regioregular Poly(3-hexylthiophene) with High Crystallinity As Revealed by Infrared Spectroscopy

详细信息    查看全文

• 作者：Yuan Yuan ; Jianming Zhang ; Jiaqian Sun ; Jian Hu ; Tongping Zhang ; Yongxin Duan
• 刊名：Macromolecules
• 出版年：2011
• 出版时间：December 13, 2011
• 年：2011
• 卷：44
• 期：23
• 页码：9341-9350
• 全文大小：1128K
• 年卷期：v.44,no.23(December 13, 2011)
• ISSN：1520-5835

文摘

Poly(3-hexyllthiophene) (P3HT) with high crystallinity was prepared by controlling the solvent evaporation rate together with the aid of chloroform vapor annealing. According to the infrared spectroscopy combined with the thermal analysis and the X-ray diffraction (XRD) data, a new crystal modification named as form I鈥?was identified for P3HT sample crystallized under extremely slow evaporation rate at low temperature (13 掳C). Such crystal modification has shorter interlayer distance than that of the more common but more disordered form I of P3HT. Moreover, it demonstrates a distinct endothermic peak around 54 掳C and a characteristic IR band at 823 cm^鈥?, which have never been reported for P3HT in the literature. The origin of the structural transition around 54 掳C is investigated in detail by temperature-dependent infrared spectroscopy combined with the in situ synchrotron WAXD measurement. It is found that, during the heating process of P3HT form I鈥?crystal, there is the form I鈥?to-form I phase transition from 30 to 60 掳C, which belongs to the solid-to-solid phase transition.