Influence of microwave irradiation on the preparation of novolacs for the shell process

1. IntroductionThe shell process is unique in its ability to makeexcellent reproducible castings with better surface finishand dimensional accuracy than castings made of othersand processes. It is also simpler to operate than many ofother casting processes 1-3]. Therefore, it has been widelyused in the foundry industry and presents a promisingfuture. In recent years the application of shell process inChina has been greatly increased and novolacs consumedin this process are up to tens of thou…

Influence of microwave irradiation on the preparation of novolacs for the shell process

In this paper, the characteristics of the preparation of novolacs for the shell process under microwave irradiation are investigated. Both polymerization and dehydration of the resins under microwave irradiation are compared with those under conventional heating and further analysis is made. The results show that compared with those under conventional heating, the polymerization and dehydration time under microwave irradiation are shortened by 85.2% and 80.7% respectively; On the other hand, the polymerization and dehydration under microwave irradiation lead to a remarkable increase in flow distance of the resins. Furthermore, the polymerization under microwave irradiation leads to reduced cure time, while the dehydration under microwave irradiation causes a slight increase in cure time.