Young’s modulus of highly oriented polypropylene films

Anomalously high values of Young’s modulus were established in polypropylene films with λ = 33.7 and the range of a nonlinear increase in the region of λ = 5–7 was found, caused by recrystallization processes. To explain these results, we proposed considering Young’s modulus in polypropylene as a linear combination of constituents which are only a function of the temperature and degree of drawing separately. __________ Translated from Khimicheskie Volokna, No. 4, pp. 12–14, July–August, 2007.