SciELO - Scientific Electronic Library Online

 
vol.19 número2Evaluating conditions for the formation of chitosan/gelatin microparticlesAdsorption of fibronectin onto polyhydroxybutyrate scaffolds applied to bone engineering índice de autoresíndice de materiabúsqueda de artículos
Home Pagelista alfabética de revistas  

Polímeros

versión impresa ISSN 0104-1428

Resumen

FERREIRA, Cintia N.; MELLO, Ivana L.  y  COUTINHO, Fernanda M. B.. Influence of the chlorinating agent of neodymium based catalysts and Cl: Nd molar ratio on butadiene polymerization. Polímeros [online]. 2009, vol.19, n.2, pp. 138-142. ISSN 0104-1428.  http://dx.doi.org/10.1590/S0104-14282009000200011.

In this work catalyst systems consisting of diisobutylaluminium hydride (DIBAH), neodymium versatate (NdV) and a chlorinating agent were employed to study the influence of the chloride source and Cl:Nd molar ratio on 1,3-butadiene polymerization and polybutadiene's characteristics (molecular weight and microstructure). The chloride sources studied were t-butyl chloride, ethylaluminium sesquichloride (EASC) and diethylaluminium chloride (DEAC). The Cl:Nd molar ratios used were 1:1, 3:1 e 5:1 for t-butyl chloride; 0.5:1, 1:1 and 3:1 for EASC and 1:1, 1.5:1, 3:1 and 5:1 for DEAC. A maximum value of Cl:Nd molar ratio exists. Moreover, DEAC showed to be more reactive than EASC and t-BuCl but t-BuCl produced higher molecular weight and cis-1,4 units contents.

Palabras llave : Ziegler-Natta catalysts; neodymium; chlorinating agent; high cis-polybutadiene.

        · resumen en Portugués     · texto en Portugués     · pdf en Portugués