The conformation of crystalline poly(phenylene sulphide)

The crystallographic structure of crystalline poly(phenylene sulphide) has been calculated from wide-angle X-ray diffraction pattern of a range of materials with different degrees of crystallinity. The orthorhombic unit cell has parameters refined by a least-squares method: a=0.868±0.002 nm, b=0.566±0.002 nm, and c=1.026±0.005 nm. The crystalline density was determined to be 1.43 g cm−3 and the enthalpy of fusion of crystalline PPS, ΔHf0, 76.5 J g−1 at the mp. computer modelling and potential energy minimisation, the torsional angle of the C–S–C bond was determined to be 108° and the phenylene groups arranged at 45° to the plane of the molecular chain. These results have been confirmed by comparison of computed and measured X-ray diffraction intensities.