Ring opening metathesis copolymerization of norbornene with norbornadiene from solutions with different mole fractions of the comonomers catalyzed by Ru-amine complexes

Autor(es)

Silva Sa, Jose L. ^[1] ; Nascimento, Eduardo S. P. ^[1] ; Fonseca, Larissa R. ^[1] ; Lima-Neto, Benedito S. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Quim Sao Carlos, BR-13560970 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Applied Polymer Science; v. 127, n. 5, p. 3578-3585, MAR 5 2013.
• Citações Web of Science: 10

Resumo

Copolymers from norbornene (NBE) with norbornadiene (NBD) were synthesized via ring opening metathesis copolymerization varying the mole fractions of the comonomers (0.8 : 0.2; 0.6 : 0.4; 0.4 : 0.6; 0.2 : 0.8) for a total monomer quantity of 5000 equivalents/{[}Ru]. The batch reactions were performed with {[}RuCl2(PPh3)2(amine)] complex types as precatalysts, where amine is perhydroazepine (1) or piperidine (2), in CHCl3 (2 mL) in the presence of ethyl diazoacetate (5 mu L) for different intervals of times (5, 30, 60, and 120 min) at 40 degrees C. The copolymers were characterized by 13C NMR. Quantitative yields of isolated materials were obtained from solutions with NBD : NBE 0.8 : 0.2 mole fraction in the presence of 1, decreasing to 70% for NBD : NBE 0.2 : 0.8 solutions. Concerning 2, the yields were 70% at most. Polymeric materials obtained with 1 were less soluble in CHCl3 than those synthesized with 2. The dependence of the reaction yields and occurrence of crosslinking on the starting NBE : NBD proportion related to reactivity of the complexes 1 and 2 were discussed. A few differences in the amines such as ancillary ligands were sufficient to change the reactivity of the [RuCl2(PPh3)] moiety complex to provide copolymers with different compositions. (c) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 (AU)

• Processo FAPESP: 06/57577-4 - Uso de combinações de ligantes ancilares de P(III), N(III), e S(II ou IV) no desenvolvimento de catalisadores de Ru(II) para polimerização via metátese de olefinas
• Beneficiário: Benedito dos Santos Lima Neto
• Modalidade de apoio: Auxílio à Pesquisa - Regular