In the previous part, we concluded that the cut-off temperature of
the used PO was situated between 20 and 25 °C. This means that at a
crystallization temperature of 25 °C, the PO exhibited a one-step crystallization
directly into the β′ polymorph (more specifically, the β′1
polymorph). The MP blends however, still showed α formation at
25 °C but not anymore at 28 °C. Addition of MP thus increases the
cut-off temperature to a temperature between 25 and 28 °C (Fig. 11).