title: Improved thermal stability of polylactic acid (PLA) composite film via PLA-β-cyclodextrin-inclusion complex systems.
abstract: The effects of the incorporation of PLA-β-cyclodextrin-inclusion complex (IC) and β-cyclodextrin (β-CD) on biopolyester PLA films were investigated. Thermal stability, surface morphology, barrier, and mechanical properties of the films were measured at varying IC (1, 3, 5, and 7%) and β-CD (1 and 5%) concentrations. The PLA-IC-composite films (IC-PLA-CFs) showed uniform morphological structure, while samples containing β-CD (β-CD-PLA-CFs) showed high agglomeration of β-CD due to poor interfacial interaction between β-CD and PLA moieties. According to the thermal property analysis, the 5% IC-PLA-CFs showed 6.6 times lower dimensional changes (6.5%) at the temperature range of 20-80°C than that of pure PLA film (43.0%). The increase of IC or β-CD content in the PLA-composite films shifted the glass transition and crystallization temperature to higher temperature regions. The crystallinity of both composite films improved by increasing IC or β-CD content. Both composite films had higher oxygen and water vapor permeability as IC or β-CD content increased in comparison to pure PLA film. All the composite films had less flexibility and lower tensile strength than the pure PLA film. In conclusion, this study shows that the IC technique is valuable to improve the thermal expansion stability of PLA-based films.
authors: Department of Food, Nutrition, and Packaging Science, Clemson University, Clemson, SC, USA.
authors: Youngjae
authors: Y
authors: Byun
authors: Department of Sustainable Biomaterials, Virginia Tech, Blacksburg, VA, USA.
authors: Katia
authors: K
authors: Rodriguez
authors: Department of Food Science and Human Nutrition, University of Illinois at Urbana/Champaign 905 S. Goodwin Ave., Urbana, IL 61801, USA.
authors: Jung H
authors: JH
authors: Han
authors: Department of Sustainable Biomaterials, Virginia Tech, Blacksburg, VA, USA. Electronic address: ytkim@vt.edu.
authors: Young Teck
authors: YT
authors: Kim
mesh_terms: D002152:Calorimetry, Differential Scanning; D019344:Lactic Acid / Q000737:chemistry*; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D011091:Polyesters; D011108:Polymers / Q000737:chemistry*; D013499:Surface Properties; D013696:Temperature; D013718:Tensile Strength; D013816:Thermodynamics; D013818:Thermogravimetry; D047392:beta-Cyclodextrins / Q000737:chemistry*
chemical_list: D011091:Polyesters; D011108:Polymers; D047392:beta-Cyclodextrins; D019344:Lactic Acid; C033616:poly(lactide)
keywords: Cyclodextrin; Inclusion complex; PLA; Thermal expansion stability