Interaction of Synthetic Resin and Pigment (III)

Interaction of the three Inorganic Pigments and the Linseed Oil Modified Alkyd Resin

Abstract

The interaction of inorganic pigment and synthetic resin was estimated for the degree of the thermal degradation of the linseed oil modified alkyd resin (abbreviated as resin) on the inorganic pigments (Si0₂, PbCrO₂, PbO) by the method of the thermal gravimetric analysis (abbreviated as TGA) and the IR spectrophotometric analysis.
The subtracting curve of the TGA's curve of the coated resin on the Si0₂ from the TGA's curve of the 100% resin was indicated the effect of the thickness of the coated resin on the Si0₂ at thermal oxidation reaction, because of the surface of the Si0₂ was nonreactive.
This subtracting curve of the 10% coated resin on the Si0₂ (weight ratio of 10% resin to 90% Si0₂) was indicated to degradated at lower temperature from 50 to 97°C than the degradation tempera-ture of the 100% resin at the same residual weight ratio by TGA.
The effect of thickness of the 1% coated resin was larger from 22 to 24% than the 10% coated resin on the Si0₂.
The subtracting curve of the TGA's curve of the 10% coated resin on the Si0₂ from the TGA's curve of the 10% coated resin on the PbCrO₄ was revealed the interaction of the coated resin and the PbCrO₄, and by this effect, the degradation took place at lower temperature.
Because of the larger interaction of the resin and the PbCrO₄, the degradation temperature of the 1% coated resin on the PbCrO₄ was so lower downed from 28°C to 34°C.
As the results of this analysis of the same process, the degradation of the resin on the PbO was occurred at three steps.
The ester group of the 1% coated resin on the PbCrO₄ was decomposed to 20% at 210°C and was violently decomposed at the upper temperature.
By the reaction of the resin and the PbO, the ester group was decomposed and the carboxylic anion group was produced in the 1% coated resin on the PbO at 120°C.