Isothermal and nonisothermal crystallization kinetics of poly(ϵ‐caprolactone)

Abstract

With increasing environmental awareness, evaluating the potential of biopolymers as a substitute for traditional materials has been of great interest. Crystallization kinetics provides fundamental knowledge required for evaluation, playing vital role in determining the final properties of the product. In this study, the isothermal and nonisothermal crystallization kinetics of poly(e-caprolactone) (PCL) were investigated with the help of various models. The Avrami model best described the isothermal crystallization kinetics, suggesting three-dimensional spherulitic growth, which was in agreement with the morphology studies; whereas the Liu model fit well under nonisothermal crystallization conditions. The failure of the Kissinger model to determine the activation energy was overcome with the Friedman model. The kinetic crystallizability determined by the Ziabacki model indicated a higher crystallization ability of PCL at lower cooling rates.

Tailor-Made, Linear, and “Comb-Like” Polyester-Based Copolymers: Synthesis, Characterization, and Thermal Behavior of Potential 3D-Printing/Electrospinning Candidates

“…Moreover, for SCL# copolymers, n values were similar to those obtained for linear PCL, with calculated values between 2.4 and 3.4 (see Table 2). It is important to highlight that these values refer to a three-dimensional heterogeneous nucleation and they are in good agreement with values already reported [33,36,56]. On the other hand, HEMACL# copolymers show values of n exponent from 1.8 to 2.6, Table 1: Chemical and thermal characterization of synthesized linear PCL and PDMS-OH homopolymers, and PCL-based copolymers.…”

“…In this sense, the understanding of the crystallization behavior of branched and linear copolymers based on PCL at temperatures lower than that corresponding to the linear homopolymer could lead to changes in processing parameters, especially if they are targeted for specific purposes. In such a sense, the thermal stabilities of the studied polymers were analyzed, and Avrami's isothermal crystallization model was employed to calculate kinetic parameters from the crystallization process [32][33][34][35][36]. It is inferred that data obtained from this analysis will provide useful information for further applications, particularly if these materials or combinations of them are planned for using as potential inks in 3D-printing or electrospinning devices [5][6][7]16].…”

“…International Journal of Polymer Science revealing that these "comb-like" copolymers adopt a twodimensional crystallization growth with heterogeneous nucleation [32,35,36,59]. The effect is strongly dependent on the number of branches, as it can be easily deduced by comparing the resulting curves for HEMACL1 and HEMACL3.…”

“…For all samples, the calculated ΔE a values were negatives. In this sense, Dhanvijay et al [36] refer this behavior to the released energy during melt to crystalline state transformation. By comparing linear PCL with SCL# and HEMACL# copolymers, the ΔE a values of HEMACL# copolymers are the highest.…”

Parameters characterizing the kinetics of the non-isothermal crystallization of polyamide 5,6 determined by differential scanning calorimetry

“…Therefore, it is concluded that the Ozawa model is not appropriate to provide an adequate description of non-isothermal crystallization kinetics of PA56. Similar results have been reported that the plots deviate from a good linearity with the Ozawa model [27,28]. The reason for that failure may be the inaccurate assumption of a constant cooling over the entire crystallization process.…”