SYNTHESIS A ND C HARACTERIZATION OF NOVOLAC RESIN AND THEIR KIN ETI C ST U DIES USING PHENOL-FORMALDEHYDE REACTIONCATALYZED BY HY DROCHLORlC ACID

Abstract

Phenol- formaldehyde novolac resins have been synthesized using 1: 0. 75 molar ratio of Phenol · to Formaldehyde. In the resulting reaction solution, HCl was added dropwise, at twelve different temperatures ranging between 35 and 90°C with an interval of 5°C with reaction time of 0. 5 hour per experiment and total of 6 hours. The P 11 of the reaction was kept constant at 0 . OJ. The structure of synthesized novolac resin have been studied by FT-IR and NMR ( 13 C & 1 H) techniques. The synthesized polymer showed a pale color solid state with a decomposition temperature of (205-280 °C) , and viscosity of 0. 055 cStokes. A kinetic study of the reaction of phenol with formaldehyde has been carried out at temperature of 85° ± 1 °C using hydrochloric acid as catalyst. The overall order of reaction rate of novolac resin was found to follow second-order rate kinetics with established rate equation. T he structure and kinetic studies o f novolac resin revealed a meaningful synthesis with maximum catalytic conversion o f phenol-formaldehyde into novolac resin at 85 °C. Results show that adopte d synthesis is convenient and cost effectivefor industrial application.