Crystallization of triethyl-citrate-plasticized poly(lactic acid) induced by chitin nanocrystals

The aim of this study was to gain a better understanding of the crystallization behavior of triethyl-citrate-plasticized poly(lactic acid) (PLA–TEC) in the presence of chitin nanocrystals (ChNCs). The isothermal crystallization behavior of PLA–TEC was studied by polarized optical microscopy, scannin...

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Detalles Bibliográficos
Autores: Singh, Shikha, Maspoch Rulduà, M. Lluïsa|||0000-0002-4813-6412, Oksman, Kristiina
Tipo de recurso: artículo
Fecha de publicación:2019
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/176510
Acceso en línea:https://hdl.handle.net/2117/176510
https://dx.doi.org/10.1002/app.47936
Access Level:acceso abierto
Palabra clave:Nanocrystals
Chitin nanocrystals
Isothermal crystallization
Microstructure
Plasticizer
Poly(lactic acid)
Cristal·lització
Nanocristalls
Àrees temàtiques de la UPC::Enginyeria dels materials::Materials plàstics i polímers
Descripción
Sumario:The aim of this study was to gain a better understanding of the crystallization behavior of triethyl-citrate-plasticized poly(lactic acid) (PLA–TEC) in the presence of chitin nanocrystals (ChNCs). The isothermal crystallization behavior of PLA–TEC was studied by polarized optical microscopy, scanning electron microscopy, differential scanning calorimetry, and X-ray diffraction (XRD). Interestingly, the addition of just 1 wt % ChNCs in PLA–TEC increased the crystallization rate in the temperature range of 135–125 °C. The microscopy studies confirmed the presence of at least three distinct types of spherulites: negative, neutral, and ring banded. The ChNCs also increased the degree of crystallinity up to 32%, even at a fast cooling rate of 25¿°C min-1. The XRD studies further revealed the nucleation effect induced by the addition of ChNCs and thus explained the faster crystallization rate. To conclude, the addition of a small amount (1 wt %) of ChNC to plasticized PLA significantly affected its nucleation, crystal size, and crystallization speed; therefore, the proposed route can be considered suitable for improving the crystallization behavior of PLA.