Novel use of glycols in polyester coating compositions

Abstract

Purpose

To study the effect of addition of free diols and triols in the coating formulation on coating properties.

Design/methodology/approach

Polyester resins were synthesised from maleic anhydride, dimerised fatty acid, neopentyl glycol and tris (2‐hydroxyethyl) isocyanurate (THEIC). Then, ethylene glycol, propylene glycol, glycerol, trimethylol propane and THEIC were added as reactive components to the coating formulation. These coatings were then analysed for various coating properties and compared with those obtained with the base resins.

Findings

The coatings obtained with the addition of these reactive components were found to have improved properties compared with those of the base resins except in cases where the reactive component itself contributed to a reduction in performance, e.g. reduced alkali resistance with the addition of THEIC.

Research limitations/implications

The addition of the free diols and triols required a corresponding increase in the amount of the curing agent to be added.

Practical implications

This process would allow for the tailoring of coatings to suit requirements to a certain extent without modifying the base resin. The addition of low molecular weight components in the coating formulation, which is then incorporated in coatings, could reduce the solvent requirement.

Originality/value

Although polyesters are an established polymeric system in coatings, the use of reactive diluents has not been investigated with the exception of unsaturated polyesters, whose curing chemistry is fundamentally different from that of polyesters focused on in this paper.

Citation

Shenoy, M.A., Sabnis, A. and D'Melo, D.J. (2006), "Novel use of glycols in polyester coating compositions", Pigment & Resin Technology, Vol. 35 No. 6, pp. 326-333. https://doi.org/10.1108/03699420610711326