Preparation or resinification

Oil-modified polyesters have been prepared by different techniques using the following methodologies. 

The following four methods have been used to manufacture polyesters. The fatty acid and monoglyceride processes are the most commonly used commercial methods  

If monoglycerides are prepared without using a catalyst, it will be necessary to apply a temperature of 280°C or higher to achieve a reasonable reaction 

In this process polyol, dibasic acid and fatty acids are made to react simultaneously at a temperature of 220-260°C until the desired polyester is obtained. In this process, fatty acids compete with the phthalic anhydride and the phthalate half ester for the available hydroxyl groups. In a special modification of the fatty acid process developed by Kraft, the dibasic acid 

This process involves the direct reaction of fatty acid, oil, polyol and dibasic acid. The ratio of fatty acid to oil must be such that a homogeneous reaction mixture results. This process has a cost advantage over the fatty acid process and gives a polyester with high viscosity, where the fatty acid represents 60-65% of the total of fatty acids and oil. Heat-polymerised oil will produce a polyester resin with an even higher viscosity.  

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