Study of Uniaxially Stretched Isotactic Poly(propylene) by 1H Solid-State NMR and IR Spectroscopy

Changes in the amount of the rigid, semi‐rigid and soft fractions, molecular mobility and domain thickness of uniaxially stretched iPP were investigated as a function of temperature, draw ratio, drawing temperature and drawing rate. Correlations are established between the thicknesses of rigid domains and the amount of the rigid fractions of uniaxially stretched iPP. Also established are correlations between the thickness of rigid domains and the molecular mobility of the rigid fraction of uniaxially stretched iPP. The drawing temperature has an important effect on the strain‐induced transformation of the spherulitic morphology of iPP to a fibrillar one.