Cure of polyester resin in a cylindrical mould heated by air

The cure of unsaturated polyester was studied by using an experiment and a mathematical model of the process. The temperature–time profiles were recorded in the centre of the resin and also at the outside wall of the cylindrical mould, and in the bulk of the heated air thermostat. A numerical model was constructed by taking into account the heat transferred by convection from the air to the mould surface and the heat transferred by conduction through the resin, as well as the heat generated by cure reaction. Introduction of the carbon base filler reduced the amount of heat generated in the composite. As a result, it lowered the temperature of the resin. The convection heat transfer coefficient was determined from independent experiments with glycerol inside the mould. Recording the temperature–time and conversion–time profiles developed within the sample, more extensive knowledge of the process can be obtained. The effects of the convection heat transfer to the mould, and the conduction heat transfer through the mould as well as the internal heat generated by the cure reaction is clearly shown, despite the complexity of the process.