Abstract：The recycled polytetrafluoroethylene(r-TPFE) was used as nucleating agent to modify Poly(butylene terephthalate) (PBT), and the non-isothermal crystallization behavior of Poly(ethylene terephthalate) and PBT/r-PTFE composite at different cooling rates was investigated by differential scanning calorimetry (DSC), respectively. The Jeziorny and Liu-Mo methods were used to analyze the non-isothermal crystallization process of pure PBT and its composite, and the activation energies of the PBT and PBT/r-PTFE composite were calculated by Kissiinger method. The results show that r-PTFE can act as efficient nucleating agent for the crystallization of PBT and obviously increase the crystallinity and crystallization rate of PBT. Compared with the Jeziorny method, the Liu-Mo method appropriately describes the non-isothermal crystallization of PBT and PBT/r-PTFE composite. Further analysis of results shows that the incorporation of r-PTFE does not obviously change the nucleation mechanism and crystal growth of PBT, but decreases the crystallization activation energy of PBT, which facilitates the crystallization of PBT.
YAO X, TIAN X, ZHANG X, et al. Preparation and characterization of poly (butylene terephthalate)/silica nanocomposites[J]. Polymer Engineering & Science, 2009, 49(4):799-807.
HWANG S, LIU S, HSU P P, et al. Effect of organoclay on the mechanical/thermal properties of microcellular injection molded PBT-clay nanocomposites[J]. International Communications in Heat and Mass Transfer, 2010, 37(8):1036-1043.
DSEHMUKH G S, PESHWE D R, PATHAK S U, et al. Nonisothermal crystallization kinetics and melting behavior of poly (butylene terephthalate)(PBT) composites based on different types of functional fillers[J]. Thermochimica Acta, 2014, 581:41-53.
VAN DER MEER D W, MILAZZO D, SANGUINETI A, et al. Oriented crystallization and mechanical properties of polypropylene nucleated on fibrillated polytetrafluoroethylene scaffolds[J]. Polymer Engineering & Science, 2005, 45(4):458-468.
MA W, WANG X, ZHANG J. Effect of MMT, SiO2, CaCO3, and PTFE nanoparticles on the morphology and crystallization of poly (vinylidene fluoride)[J]. Journal of Polymer Science Part B:Polymer Physics, 2010, 48(20):2154-2164.
MA W, WANG X, ZHANG J. Crystallization kinetics of poly (vinylidene fluoride)/MMT, SiO2, CaCO3, or PTFE nanocomposite by differential scanning calorimeter[J]. Journal of Thermal Analysis and Calorimetry, 2011, 103(1):319-327.
JURCZUK K, GALESKI A, PIONKOWSKA E. All-polymer nanocomposites with nanofibrillar inclusions generated in situ during compounding[J]. Polymer, 2013, 54(17):4617-4628.
JEZIORNY A. Parameters characterizing the kinetics of the non-isothermal crystallization of poly(ethylene terephthalate) detetmined by DSC[J]. Polymer, 1978, 19(10):1142-1149.
LIU T, MO Z, WANG S, et al. Non-isothermal melt and cold crystallization kinetics of poly(ary1 ether ether ketone ketone)[J]. Polym Eng Sci, 1997, 37(3):568-575.
AVRAMI M. Kinetics of phase changeⅡ:transformation-time relations for random distribution of nuclei[J]. J Chem Phys, 1940, 8(2):212-224.
KISSINGER H E. Reaction kinetics in differential thermal analysis[J]. Analytical Chemistry, 1957, 29(11):1702-1706.