Titre : |
Copolymers of styrene and maleic anhydride : reactivity ratio, physical behavior and spectral properties |
Type de document : |
texte imprimé |
Auteurs : |
Suman Kumari, Auteur ; Dhirendra Nigam, Auteur ; Devendra Agarwal, Auteur ; Indira Nigam, Auteur |
Année de publication : |
2008 |
Note générale : |
Bibliogr. |
Langues : |
Anglais (eng) |
Catégories : |
Analyse spectrale Copolymère styrène acide maléique Polymères -- Propriétés physiques
|
Index. décimale : |
667.9 Revêtements et enduits |
Résumé : |
Radical polymerization of styrene and maleic anhydride was carried out in N,N-dimethylformamide (DMF) as a solvent at the temperature of 80°C using benzoylperoxide as initiator. The monomer ratio was varied in the range of 0.5:1 to 4:1. The copolymer compositions were determined by CHN-elemental analysis. The copolymers were characterized by CNMR spectroscopy and was used to determine the copolymer composition. These values are comparable to those obtained from CHN-analysis although the mole fractions of styrene as observed by elemental analysis in the copolymers is slightly higher than the corresponding values observed by CNMR spectra. The ratio of styrene and maleic anhydride in the copolymer was in the range of 1.02 - 1.17 up to the monomer feed ration 2:1 and increased to about 1.53 for feed ratio of 4:1. This shows styrene and maleic anhydride have a strong tendency to form an alternating copolymer which deviates slightly when higher concentration of styrene is taken in the feed. This tendency can be explained on the basis of either of two mechanisms viz. chain transfer complex formation as well as penultimate effect due to presence of a polar solvent. The reactivity ration were determined by various methods viz Myao Lewis, Fineman Ross method, Kelen Tudos methods. The more precise value of reactivity ratio could be determined by Kelen Tudos as compared to other methods. The reactivity ratios determined by these methods shows that r1r2 <<1 which further indicated that on copolymerization of styrene and maleic anhydride, an alternating copolymer was formed. |
En ligne : |
https://drive.google.com/file/d/1-wwSBOnTPnAHD8snszDxxg2i3-m3z9gM/view?usp=drive [...] |
Format de la ressource électronique : |
Pdf |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=6961 |
in PAINTINDIA > Vol. LVIII, N° 11 (11/2008)