Experimental study of the influence of raw material impurities on yellowness index of transesterification polycarbonate

Abstract

This article covers a quantitative experimental study on the influence of raw materials and materials of construction impurities on polycarbonate color as expressed by a solution yellowness index. Major impurities in the production process were identified, synthesized, and spiked into the baseline materials. A fractional factorial experimental design was executed to provide some information of the influence of impurities as corresponding to levels similar to those occurring in the manufacturing practice. Analysis of the experimental design showed that isopropenylphenol (IPP), methoxyphenyl benzoate (MOB) and 9,9-dimethylxanthene (DMX) are the main producers of color bodies. A quantitative expression was derived which can be used to predict manufacturing problems with regards to color.