TOTAL AND PARTIAL ERUCATE OF PENTAERYTHRITOL - INFRARED-SPECTROSCOPY STUDY OF RELATIONSHIP BETWEEN STRUCTURE, REACTIVITY, AND THERMAL-PROPERTIES

Esters of neopentylpolyols are an important starting base for syntheti c lubricants. These bulky esters are generally prepared by an esterifi cation reaction between a carboxylic acid and a neopentylpolyol. Becau se neopentylpolyols have a number of primary alcohol sites, a variety of partial esters is formed before total esters. In the present study, we investigated the reaction between pentaerythritol and erucic acid. The composition of the reaction mixture in erucic acid, partial ester s, and total esters was monitored by thin-layer chromatography, couple d with flame-ionization detection. The pure esters and the esters in s olution at different concentrations in xylene at different temperature s were analyzed by Fourier transform infrared spectroscopy. Erucic aci d and partial esters in xylene coexist in the free form and as bound c omplexes. These findings furthered understanding of the reactivity and thermal properties of the partial esters.