The thermal behavior of poly(ethylene-co-2,2-bis[4-(ethylenoxy)-1,4-phenylene]propane terephthalate) (PET/BHEEBT) copolymers was investigated by thermogravimetric anal. and differential scanning calorimetry. A good thermal stability was found for all the samples. The thermal anal. carried out using DSC technique showed that the Tm of the copolymers decreased with increasing BHEEBT unit content, differently from Tg, which on the contrary increased. Wide-angle X-ray diffraction measurements permitted identifying the kind of cryst. structure of PET in all the semicryst. samples. The multiple endotherms similar to PET were also evidenced in the PET/BHEEBT samples, due to melting and recrystn. processes. By applying the Hoffman-Weeks' method, the Tm° of PET and its copolymers was derived. The isothermal crystn. kinetics was analyzed according to Avrami's treatment and values of the exponent n close to 3 were obtained, independently of Tc and compn. Moreover, the introduction of BHEEBT units was found to decrease PET crystn. rate. Lastly, the presence of a crystal-amorphous interphase was evidenced.
M. Vannini, L. Finelli, N. Lotti, M. Colonna, C. Lorenzetti, A. Munari (2005). Thermal behavior and crystallization kinetics of random poly(ethylene-Co-2,2-bis[4-(ethylenoxy)-1,4-phenylene]propane terephthalate) copolyesters. JOURNAL OF POLYMER SCIENCE. PART B, POLYMER PHYSICS, 43(12), 1441-1454 [10.1002/polb.20429].
Thermal behavior and crystallization kinetics of random poly(ethylene-Co-2,2-bis[4-(ethylenoxy)-1,4-phenylene]propane terephthalate) copolyesters.
VANNINI, MICAELA;FINELLI, LARA;LOTTI, NADIA;COLONNA, MARTINO;LORENZETTI, CESARE;MUNARI, ANDREA
2005
Abstract
The thermal behavior of poly(ethylene-co-2,2-bis[4-(ethylenoxy)-1,4-phenylene]propane terephthalate) (PET/BHEEBT) copolymers was investigated by thermogravimetric anal. and differential scanning calorimetry. A good thermal stability was found for all the samples. The thermal anal. carried out using DSC technique showed that the Tm of the copolymers decreased with increasing BHEEBT unit content, differently from Tg, which on the contrary increased. Wide-angle X-ray diffraction measurements permitted identifying the kind of cryst. structure of PET in all the semicryst. samples. The multiple endotherms similar to PET were also evidenced in the PET/BHEEBT samples, due to melting and recrystn. processes. By applying the Hoffman-Weeks' method, the Tm° of PET and its copolymers was derived. The isothermal crystn. kinetics was analyzed according to Avrami's treatment and values of the exponent n close to 3 were obtained, independently of Tc and compn. Moreover, the introduction of BHEEBT units was found to decrease PET crystn. rate. Lastly, the presence of a crystal-amorphous interphase was evidenced.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
