Morphological and structural properties of poly[bis(p-phenylphenoxy)phosphazene]

Poly[bis(p-phenylphenoxy)phosphazene] (PB(4-Ph)PP) has been investigated employing X-ray diffraction technique and electron microscopy. Its unit cell dimensions were determined to be a = 4,18 nm, b = 1,83 nm and c = 0,957 nm with space group Pca2₁. At 21 5–220°C , PB(4-Ph)PP transforms into an anisotropic liquid-like phase corresponding to a new molecular ordering array. The thicker films are composed of the linked globules approximately 100 nm in diameter. Upon drawing, the globules transform into a rod-like morphology 15–40 nm in width and exhibit a highly oriented X-ray diffraction pattern. These unusual morphological features have been compared with features found in poly[bis(phenoxy)phosphazene] and poly[bis(halophenoxy)phosphazene] polymers. X-ray diffraction and crystallization results support a smectic-like side chain morphology.