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Polyoxometalate functionalized matrix material: synthesis, characterization, reductive and thermal degradation kinetics. SN APPLIED SCIENCES 2020. [DOI: 10.1007/s42452-020-2396-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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Gnanasekar P, Yan N. Synthesis and thermo-mechanical properties of novel spirobiindane based epoxy nanocomposites with tryptophan as a green hardener: Curing kinetics using model free approach. Polym Degrad Stab 2019. [DOI: 10.1016/j.polymdegradstab.2019.03.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Rishwana SS, Pitchaimari G, Vijayakumar C. Studies on structurally different diamines and bisphenol benzoxazines. HIGH PERFORM POLYM 2015. [DOI: 10.1177/0954008315587125] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The compounds resorcinolbisbenzoxazine, quinolbisbenzoxazine, p-phenylene diaminebisbenzoxazine, and m-phenylenediaminebisbenzoxazine are prepared. The structural and thermal characterizations of the materials are done using Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H NMR) and 13C NMR, and differential scanning calorimetry. Both FTIR and NMR studies reveal the presence of oxazine rings in the synthesized monomers. The curing exotherm of these bisbenzoxazines is much influenced by the nature of the aromatic unit present in the chosen compound and also on the type of the benzoxazine unit in the system. Curing kinetics is performed using Flynn–Wall–Ozawa, Vyazovkin, and Friedman methods. The apparent activation energies ( Ea-C) for the thermal curing of the synthesized monomers varied and are dependent on the nature and the position of the functional groups present in the compound. The highest Ea-C values are noted for the compounds having the functionalizations being para oriented.
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Affiliation(s)
- S. Shamim Rishwana
- Department of Chemistry, Kamaraj College of Engineering and Technology, K. Vellakulam, Tamil Nadu, India
| | - G. Pitchaimari
- Department of Polymer Technology, Kamaraj College of Engineering and Technology, K. Vellakulam, Tamil Nadu, India
| | - C.T. Vijayakumar
- Department of Polymer Technology, Kamaraj College of Engineering and Technology, K. Vellakulam, Tamil Nadu, India
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Rishwana SS, Mahendran A, Vijayakumar CT. Studies on structurally different benzoxazines. HIGH PERFORM POLYM 2014. [DOI: 10.1177/0954008314561806] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Bisbenzoxazines were prepared by the condensation of the respective bisphenols bisphenol A (BA), indane bisphenol (IBP), and spirobiindane bisphenol (SBI) with paraformaldehyde and aniline. The apparent activation energies for the polymerization curing process ( Ea-C) and the degradation process ( Ea-D) were calculated using Flynn–Wall–Ozawa, Vyazovkin, and Friedman methods. The variation in Ea-C noted for the thermal curing of different bisbenzoxazines is attributed to the operation of different mechanisms for the curing process. The variation of the Ea-D for the degradation of spirobiindane benzoxazine polymerized at high temperature was different from the other materials investigated and is attributed to its complex structure. The volatile products obtained during the thermal degradation of the polymers were analyzed using thermogravimetric–Fourier transform infrared analyses. Aniline was found to be the major product and was released during the primary degradation. At higher temperatures, breakage of the isopropylidine, indane, and biindane structural entities were favored.
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Affiliation(s)
- S Shamim Rishwana
- Department of Chemistry, Kamaraj College of Engineering and Technology, K. Vellakulam Post, Madurai, Tamil Nadu, India
| | - A Mahendran
- Competence Center for Wood Composites and Wood Chemistry Ltd., Area Wood Carinthian Competence Center (W3C), Klagenfurter strasse 87–89, St.Veit an der Glan, Austria
| | - CT Vijayakumar
- Department of Polymer Technology, Kamaraj College of Engineering and Technology, K. Vellakulam Post, Madurai, Tamil Nadu, India
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Surender R, Thamaraichelvan A, Alam S, Vijayakumar CT. Bismaleimide and bispropargyl ether blends: Curing kinetics—Model free approach. POLYMER SCIENCE SERIES B 2014. [DOI: 10.1134/s1560090414050157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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