Structural analysis, rheological behaviour and the performance of films for surface coatings' application of heated and unheated Nahar seed oil

The structural analysis and rheological behaviour of unheated Nahar seed oil and oil heated at two different temperatures viz. (250 ± 5) °C and (315 ± 5) °C for a specified time, and the coating performance of the films of the same have been studied. The various physical properties of the unheated and heated oil were studied by determining acid value, iodine value, saponification value and specific gravity. The structural variation during heat treatment at different temperatures was analysed by FT-IR, 1H NMR spectroscopies and GPC analysis. The rheological behaviour i.e. variation of viscosity with time of the heated oil has been studied by Brookfield viscometer. Also an attempt has been made to establish the co-relationships between variation of viscosity and time of heating of the heated oil. The coating performance of the films prepared from unheated and heated Nahar oil has been investigated by measuring pencil hardness, gloss, flexibility, pressure test and chemical resistance. The films from heated oil showed better drying time over the film from unheated oil.