Non-isothermal crystallization kinetics of hybrid carbon nanotube - silica/ polyvinyl alcohol Nanocomposites

Autor: Cherif Dridi, Siwar Jebril, Bessem Ben Doudou, Slim Zghal
Rok vydání: 2019
Předmět:
Zdroj: Journal of Polymer Research. 26
ISSN: 1572-8935
1022-9760
DOI: 10.1007/s10965-019-1931-1
Popis: In this paper, a new nanocomposite based on polyvinyl alcohol (PVA) / hybrid carbon nanotube (CNT) - silica (SiO2) with different amounts (1 and 5 wt%) of hybrid nanostructures are successfully prepared by solution-casting method. The crystallization kinetics of PVA and its nanocomposites under non-isothermal conditions are evaluated by differential scanning calorimetry (DSC). Jeziorny, Ozawa and Mo models are used to determine the PVA and PVA/CNT-SiO2 crystallization kinetics parameters. It was found that the Ozawa method is not suitable for the description of the non-isothermal crystallization behavior of PVA and its nanocomposites, while the Jeziorny and Mo models fitted the experimental data very well. Furthermore, Jeziorny analysis indicated that the crystallization process of PVA and PVA/CNT-SiO2 nanocomposites involve two main stages, the primary and secondary crystallization process. Additionally, the activation energy of non-isothermal crystallization is also estimated by using Friedman method, Kissinger method and isoconversional method modified by Vyazovkin, respectively. The latter method is more appropriate to calculate the non-isothermal crystallization activation energy of both PVA and PVA/CNT-SiO2 nanocomposites. The Hoffman-Lauritzen parameters (U* and Kg) were also determined. Based on the findings of Zc values in Jeziorny model, F(T) values in Mo model, crystallization activation energy and the Hoffman-Lauritzen parameters, it was concluded that hybrid carbon nanotube - silica nanostructures promoted PVA non-isothermal crystallization process.
Databáze: OpenAIRE
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