Crystal structure of poly[bis(3,4-dimethylphenoxy)phosphazene]

✍ Scribed by T. Miyata; K. Yonetake; T. Masuko

• Publisher: Springer
• Year: 1994
• Tongue: English
• Weight: 671 KB
• Volume: 29
• Category: Article
• ISSN: 0022-2461
• DOI: 10.1007/bf00363441

✦ Synopsis

The crystal structure and chain conformation of polyibis(3,4-dimethylphenoxy)phosphazene] -PB(dMe)PP -have been studied by X-ray diffraction techniques. The unit cell of this polymer shows an orthorhombic form with the crystallographic parameters a=2.05, b= 1.49, c (chain axis) =0.998 nm. Its space group is determined as Pbcn-D~#where the molecular chains are located at the centre and each corner of the unit cell, which contains eight monomeric units; these molecular chains possibly have a -(transzcis)2conformation. The R factor calculated from the final crystal structure was estimated as 16.9%. As with other types of polyorganophosphazenes, the thermotropic transformation in PB(dMe)PP takes place from the three-dimensionally ordered state to its two-dimensional psuedohexagonal form (ah = 1.49 nm), accompanied by a latent heat change at 96 ~ * Author to whom all correspondence should be addressed. 0022-2461 9 1994 "Chapman & Hall ture of PB(dMe)PP in detail by XRD studies, and also investigate thermal phase transitions of this polymer by means of XRD and differential scanning calorimetry (DSC).