Radical copolymerization of acrylonitrile with 2,2,2-trifluoroethyl acrylate for dielectric materials: Structure and characterization
2013 (English)In: Journal of Polymer Science Part A: Polymer Chemistry, ISSN 0887-624X, E-ISSN 1099-0518, Vol. 51, no 18, 3856-3866 p.Article, review/survey (Refereed) Published
Radical copolymerization based on acrylonitrile (AN) and 2,2,2-Trifluoroethyl acrylate (ATRIF) initited by AIBN was investigated in acetonitrile solution. The resulting poly(AN-co-ATRIF) copolymers were characterized by 1 H, 13 C, and 19 F NMR and IR spectroscopy, and size exclusion chromatography (SEC). Their compositions were assessed by 1 H NMR. The kinetics of radical copolymerization of AN with ATRIF was investigated from sereval experiments achieved at 70 degrees C from initial [AN](0)/[ATRIF](0) molar ratios ranging between 20/80 and 80/20 and was enabled to determine the reactivity ratios of both comonomers. From the monomer-polymer copolymerization curve, the Fineman-Ross and Kelen-Tudos laws enabled to assess the reactivity ratios (r(AN) = r(1) = 1.25 +/- 0.04 and r(ATRIF) = r(2) = 0.93 +/- 0.05 at 70 degrees C) while the revised patterns scheme led to r(12) = r(AN) = 1.03, and r(21) = r(ATRIF) = 0.78 at 70 degrees C. In all cases, rAN x rATRIF product was close to unity, which indicates that poly(AN-co-ATRIF) copolymers exhibit a random structure. This was also confirmed by the Igarashi's and Pyun's laws which revealed the presence of AN-ATRIF, AN-AN, and ATRIF-ATRIF dyads. The Q and e values for ATRIF were also assessed (Q(2) = 0.62 and e(2) = 0.93). The glass transition temperature values, Tg, of these copolymers increased from 17 to 61 degrees C as the molar percentage of ATRIF decreased from 77 to 16% in the copolymer. Thermogravimetry analysis of poly(AN-co-ATRIF) copolymers showed a good thermal stability compared to that of poly(ATRIF) homopolymer due to incorporation of AN comonomer.
Place, publisher, year, edition, pages
2013. Vol. 51, no 18, 3856-3866 p.
acrylonitrile, fluorocopolymer, microstructure, radical copolymerization, reactivity ratio, thermal properties, 2, 2.2-trifluoroethyl acrylate
IdentifiersURN: urn:nbn:se:kth:diva-127736DOI: 10.1002/pola.26783ISI: 000322656500010ScopusID: 2-s2.0-84881312626OAI: oai:DiVA.org:kth-127736DiVA: diva2:646369
FunderSwedish Research Council, VR 2008-6002
QC 201309092013-09-092013-09-052013-09-09Bibliographically approved