Crystallization Kinetics and Melting Behaviour of the Novel Biodegradable Polyesters Poly(propylene azelate) and Poly(propylene sebacate)

2008 ◽  
Vol 210 (1) ◽  
pp. 90-107 ◽  
Author(s):  
George Z. Papageorgiou ◽  
Dimitris S. Achilias ◽  
Dimitrios N. Bikiaris
Keyword(s):  
Crystallization Kinetics ◽  
The Novel ◽  
Melting Behaviour ◽  
Biodegradable Polyesters ◽  
Poly Propylene

scholarly journals Memory effect in melting behaviour, crystallization kinetics and morphology of poly(propylene terephthalate)

e-Polymers ◽  
2003 ◽  
Vol 3 (1) ◽  
Author(s):  
Laura Sisti ◽  
Lara Finelli ◽  
Nadia Lotti ◽  
Corrado Berti ◽  
Andrea Munari
Keyword(s):  
Thermal Treatment ◽  
Optical Microscopy ◽  
Melting Temperature ◽  
Crystallization Kinetics ◽  
Isothermal Crystallization ◽  
Crystallization Process ◽  
Nucleation Theory ◽  
Melting Behaviour ◽  
Non Linear ◽  
Poly Propylene

AbstractCrystallization kinetics and melting behaviour of poly(propylene terephthalate) (PPT) were investigated by means of differential scanning calorimetry and hot-stage optical microscopy. Isothermal crystallization kinetics was analysed according to the Avrami treatment. The effects of temperature and duration of melting on the overall rate of isothermal crystallization were studied: the rate was found to decrease with increasing melting temperature and melting time. This result was discussed on the basis of the gradual destruction of predetermined athermal nuclei. Values of the Avrami exponent close to 3 were obtained, regardless of the adopted thermal treatment and the crystallization temperature, Tc, in agreement with a crystallization process originating from predetermined nuclei and characterized by three-dimensional spherulitic growth. As a matter of fact, spacefilling spherulites were observed by optical microscopy at all Tc’s, independent of the applied thermal treatments. For each of them, the rate of crystallization became lower as Tc increased, as usual at low undercooling where the crystallization process is controlled by nucleation. The observed multiple endotherms, which are commonly displayed by polyesters, were influenced by Tc and ascribed to melting and recrystallization processes. Linear and non-linear treatments were applied in order to estimate the equilibrium melting temperature for PPT, by using the corrected melting temperatures. The non-linear estimation yielded an about 33°C higher value with respect to the one obtained by means of the linear approach. Through the analysis of secondary nucleation theory, the classical II→III transition was found to occur at a temperature of 194°C. The average work of chain folding for nucleation was determined to be c. 5.2 kcal/mol. The heat of fusion was correlated to the specific heat increment for samples with different degree of crystallinity and the results were interpreted on the basis of the existence of an interphase, whose amount was found to depend on the thermal treatment the polymer was subjected to.

Characterization and Crystallization Kinetics of in situ Prepared Poly(propylene terephthalate)/SiO2 Nanocomposites

2009 ◽  
Vol 211 (1) ◽  
pp. 66-79 ◽  
Author(s):  
Dimitris S. Achilias ◽  
Dimitrios N. Bikiaris ◽  
Efthimios Papastergiadis ◽  
Dimitris Giliopoulos ◽  
George Z. Papageorgiou
Keyword(s):  
Crystallization Kinetics ◽  
Sio2 Nanocomposites ◽  
Poly Propylene ◽  
Kinetics Of

The effect of microcrystalline cellulose on poly(propylene) crystallization. An investigation of nonisothermal crystallization kinetics

2019 ◽  
Vol 6 (6) ◽  
pp. 065313 ◽  
Author(s):  
Tamíris R Silva ◽  
Ingridy D S Silva ◽  
Querem A F Andrade ◽  
Renate M R Welen ◽  
Eliton S Medeiros ◽  
...  
Keyword(s):  
Crystallization Kinetics ◽  
Microcrystalline Cellulose ◽  
Nonisothermal Crystallization ◽  
Nonisothermal Crystallization Kinetics ◽  
Poly Propylene
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