Influence of the amount of catalyst and initial pH on the phenolic resol resin formation G. Astarloa-Aierbea, J.M. Echeverrı ´ab, A. Va ´zquezc, I. Mondragona,* aEscuela Universitaria Ingenierı ´a Te ´cnica Industrial, Dpto. Ingenierı ´a Quı ´mica y Medio Ambiente, Universidad Paı ´s Vasco/Euskal Herriko Unibertsitatea, Av. Felipe IV, 1B 20011 Donostia, Spain bBakelite Ibe ´rica. Ctra. a Navarra. Epele, 39 20120 Hernani, Spain cInstituto de Investigaciones en Ciencia y Tecnologı ´a de Materiales (INTEMA), Universidad Nacional de Mar del Plata. C/. Catamarca, 2317. 7600 Mar del Plata, Argentina Received 23 March 1999; received in revised form 11 July 1999; accepted 19 July 1999 Abstract The influence of the added amount of triethylamine as phenolic resol resin catalyst and that of the initial pH were studied for resols synthesized at 80?C with F?P ? 1?8? The evolution of phenol and first formed addition products were quantitatively followed by high- performance liquid chromatography (HPLC) and final prepolymers were analyzed by kinetically and mechanistically affected the prepolymer formation. The higher the amount of added catalyst the higher reactant consumption rates and product formation rates. The ortho directing characteristics of triethylamine for the addition of formaldehyde onto phenolic sites were observed. It could be stated that two mechanisms for the addition offormaldehyde Influence of the amount of catalyst and initial pH on the phenolic resol resin formation. Available from: http://www.researchgate.net/publication/229201374_Influence_of_the_amount_of_catalyst_and_initial_pH_on_the_phenolic_resol_resin_formation [accessed Jun 6, 2015].
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