Study on non‐isothermal crystallization kinetics of Poly (butylene terephthalate)/Poly (ethylene terephthalateco‐1,4‐cylclohexylenedimethylene terephthalate) blends

Poly (butylene terephthalate) (PBT)/poly (ethylene glycol‐co‐cyclohexane‐1, 4‐dimethanolterephthalate) (PETG) blends were prepared by melt blending using a twin screw extruder. The non‐isothermal crystallization behaviors of PBT/PETG blends were investigated using differential scanning calorimetry (DSC). The results showed that the crystallization peaks of the PBT/PETG blends moved gradually toward lower temperature and the crystallinity decreased with the increase of PETG content. The PBT/PETG blends all show double melting peaks, which the low‐melting peak temperature T m 1 becomes lower as the cooling rate increases, but the high‐melting peak temperature T m 2 is not related to the cooling rate. The Jeziorny's method showed that the faster the cooling rate is, the shorter the crystallization time is required for the PBT/PETG blends. The Mo's method showed that the crystallization rate of the blends initially decreased and then increased with the addition of more PETG. The activation energy of non‐isothermal crystallization calculated by the Kissinger method is similar to that of the Takhor method. Highlights The efficient blending of PBT and PETG was realized by twin screw extruder, which opened up a new way for the preparation of polymer materials. The crystallization behavior of PBT/PETG blends was successfully regulated, and the effect of PETG content on the crystallization peak temperature and crystallinity was revealed. The crystallization characteristics and kinetic behavior of the blends were comprehensively evaluated by DSC, Jeziorny method, Mo Zhishen method, and Kissinger method.