1. These are crystalline polymers with chain orientation virtually perfect in one direction. 2. Partially crystalline polymers present complex spectra as they are multi-phase materials, in which the molecular motions are more restricted in the crystalline phase than in the amorphous phase. 3. A particularly effective way of examining partially crystalline polymers is by X-ray diffraction. 4. Even with carefully annealed specimens, it is thought that the equilibrium melting temperature of the completely crystalline polymer T m is never actually attained. 5. While spherulites are characteristic of crystalline polymers, they have also been observed to form in low molar mass compounds which are crystallized from highly viscous media. |