An advanced method for calculation of infrared parameter to quantitatively identify rubber grade in a multi-component rubber blend

Abstract

This article focusses on quantitative determination of each rubber from a multi-rubber blend, using an efficient method of infrared (IR) spectroscopy and is a continuation of a previous work which was focused on finding an IR blend parameter (PIR)) directed to quantitatively reverse engineer a binary rubber blend. The present method, is aimed to determining of IR parameter (PH(IR)) for each rubber, which could then be judiciously used for the quantitative determination of all the rubbers present in a blend. The approach has been based on experimental characterization of baseline subtracted characteristic IR absorbance peak height and numerical calculation by using Beer Lambert law, with the implementation of extinction co-efficient, (ε) and the depth of penetration, (dp) of the characteristic IR beam at a defined wavenumber in the analyzed rubber. Variously compounded and cured binary and ternary blends of natural rubber (NR), styrene butadiene rubber (SBR) and polybutadiene rubber (BR) were analyzed by using infrared spectroscopy to validate the concept of PH(IR). The approach has been implemented and the finally calculated PH(IR) detected the grade of present rubber types, identical with the compounded formulations. Thus the concept has been approved. © 2018