Concept of five-levels–four-factors central composite rotatable design was utilized for the optimization of reaction conditions of cardanol-based phenol formaldehyde resin production, by employing response surfaces methodology, to establish a relationship between the process variables and the extent of conversion under a wide range of operating conditions which resulted in different extent of conversions. The design was based to study the effect of reaction temperature, catalyst concentration, reaction time, pH and cardanol-to-formaldehyde molar ratio to get the maximum extent of conversion. Geometrical representation of the mathematical models in three-dimensional surface plots served as a good aid in understanding the behavior of reaction under different operating conditions. A statistical model predicted that the highest conversion yield of novolac resin would be 97% at the optimized reaction conditions. These predicted values for optimum process conditions were in good agreement with experimental data.
