title: Thermal degradation behaviour of nanoamphiphilic chitosan dispersed poly (lactic acid) bionanocomposite films.
abstract: In the present study, nano-amphiphilic chitosan termed as chitosan-grafted-oligo l-lactic acid (CH-g-OLLA), is synthesized by microwave initiated insitu condensation polymerization. The synthesized CH-g-OLLA becomes hydrophobic in nature due to chemical bond formation between chitosan backbone and OLLA chains. Further, CH-g-OLLA (30%) bionanocomposite is used as a nanofiller in poly (lactic acid)/chitosan-grafted-oligo l-lactic acid (PLA/CH-g-OLLA) bionanocomposite films. Surface morphology shows a homogeneous dispersion of CH-g-OLLA in the form of spherical aggregates, which vary in the range of ∼20 to 150nm. Non-isothermal degradation kinetics, proposed by Kissinger, Kissinger-Akahira-Sunose, Flynn-Wall-Ozawa and Augis & Bennett models, are utilized to estimate the activation energies (Ea) for PLA, which are 254.1, 260.2, 257.0 and 259.1kJmol-1respectively. The reduction in Eavalues of bionanocomposite films may be elucidated by intermolecular distance and enrichment in chain mobility. The evolved gaseous products like hydrocarbons, carbon dioxide, carbon monoxide and cyclic oligomers are successfully identified with TG-FTIR analysis.
authors.affiliation: Department of Chemical Engineering, Indian Institute of Technology Guwahati, Assam, 781039, India.
authors.forename: Akhilesh Kumar
authors.initials: AK
authors.lastname: Pal
authors.affiliation: Department of Chemical Engineering, Indian Institute of Technology Guwahati, Assam, 781039, India. Electronic address: vkatiyar@iitg.ernet.in.
authors.forename: Vimal
authors.initials: V
authors.lastname: Katiyar
mesh_terms: D001672:Biocompatible Materials / Q000138:chemical synthesis*; D002245:Carbon Dioxide / Q000737:chemistry; D002248:Carbon Monoxide / Q000737:chemistry; D060326:Chemistry Techniques, Synthetic; D048271:Chitosan / Q000031:analogs & derivatives / Q000138:chemical synthesis*; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D008567:Membranes, Artificial; D008872:Microwaves; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D011091:Polyesters / Q000737:chemistry*; D058105:Polymerization; D013499:Surface Properties; D013501:Surface-Active Agents / Q000138:chemical synthesis*; D013816:Thermodynamics
chemical_list: D001672:Biocompatible Materials; D008567:Membranes, Artificial; D011091:Polyesters; D013501:Surface-Active Agents; D002245:Carbon Dioxide; C033616:poly(lactide); D002248:Carbon Monoxide; D048271:Chitosan
keywords: Nanoamphiphilic chitosan; Poly (lactic acid); Thermal degradation kinetics