Lifetime predictions of non-ionic and ionic biopolymers: kinetic studies by non-isothermal thermogravimetric analysis

نویسندگان

چکیده

Abstract In this paper, films based on sustainable polymers with variable charge have been investigated by non-isothermal thermogravimetry in order to predict their lifetime, which is a key parameter for potential use numerous technological and biomedical applications. Specifically, chitosan has selected as positively charged biopolymer, while alginate chosen negatively biopolymer. Among non-ionic polymers, methylcellulose investigated. Thermogravimetric measurements at heating rates (5, 10, 15 20 °C min −1 ) performed all the study degradation kinetics using isoconversional procedures combined ‘Master plot’ analyses. Both integral (KAS Starink methods) differential (Friedman method) shown that possesses highest energetic barrier decomposition. Based Master plot analysis, decomposition of ionic can be described R2 kinetic model (contracted cylindrical geometry), reflects D2 mechanism (two-dimensional diffusion). The determination both parameters (activation energy pre-exponential factor) used determine decay time functions several biopolymers. obtained insights helpful development durable electrostatic characteristics. Graphical abstract

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ژورنال

عنوان ژورنال: Emergent materials

سال: 2021

ISSN: ['2522-574X', '2522-5731']

DOI: https://doi.org/10.1007/s42247-021-00259-6