Τίτλος:
Statistical copolymers of N-vinylpyrrolidone and benzyl methacrylate via RAFT: Monomer reactivity ratios, thermal properties and kinetics of thermal decomposition
Γλώσσες Τεκμηρίου:
Αγγλικά
Περίληψη:
Statistical copolymers of N-vinylpyrrolidone (NVP) with benzyl methacrylate (BzMA) were prepared by Reversible Addition-Fragmentation chain Transfer Polymerization (RAFT), employing three different xanthates as RAFT agents: [(O-ethylxanthyl)methyl]benzene, [1-(O-ethylxanthyl)ethyl]benzene and O-ethyl S-(phthalimidylmethyl) xanthate. The reactivity ratios were estimated using the Fineman-Ross, inverted Fineman-Ross, Kelen-Tüdos and extended Kelen-Tüdos linear graphical methods, as well as the computer program COPOINT. Structural parameters of the copolymers were obtained by calculating the dyad sequence fractions and the mean sequence length. All the methods are in agreement that the probability for the incorporation of BzMA units is much greater than for that of NVP units. The glass-transition temperature (Tg) values of the copolymers were measured by Differential Scanning Calorimetry and examined by means of several theoretical equations, allowing for the prediction of these Tg values. Subsequently, a systematic and detailed investigation of the thermal degradation of these copolymers compared with that of the respective homopolymers, was carried out by Thermogravimetric Analysis, within the framework of the Ozawa-Flynn-Wall and Kissinger methodologies. As expected, the thermal stability of the copolymers is influenced by the structure of the substituents of the thiocarbonylthio end groups due to the RAFT agents. © 2018 Taylor & Francis Group, LLC.
Συγγραφείς:
Roka, N.
Pitsikalis, M.
Περιοδικό:
Journal of Macromolecular Science, Part A: Pure and Applied Chemistry
Εκδότης:
Taylor and Francis Inc.
Λέξεις-κλειδιά:
Benzene; Copolymerization; Decomposition; Differential scanning calorimetry; Free radical polymerization; Glass transition; Living polymerization; Polymerization; Thermodynamic properties; Thermodynamic stability; Thermogravimetric analysis; Vinyl resins, benzyl methacrylate; Monomer reactivity ratios; N vinylpyrrolidone; RAft polymerization; Reversible addition-fragmentation chain transfer polymerization; Statistical copolymers; Structural parameter; Theoretical equation, Polyacrylates
DOI:
10.1080/10601325.2017.1403858
