Professor Harada encountered the world of polymer materials during her undergraduate years at Kansai University. After proceeding to graduate school, she started serious research into network polymers* centered on epoxy resin. As epoxy resin embodies superior properties such as adhesiveness and heat resistance, it has been used for adhesive bond and paint materials for some time already. It is also used in the field of advanced industry for such purposes as repairing expressway bridge piers and aircraft equipment, and provides excellent electrical insulation. Due to these properties, epoxy resin is used in large quantities in Japan as an IC chip sealant and also in circuit boards. IC chips produce heat, and epoxy resin is used to absorb it to prevent malfunction. Professor Harada began researching ways to enhance the thermal conductivity of epoxy resin.
*Network polymer: 3-dimentional network structured polymer
Macromolecule can be divided in two different types. One is epoxy resin and thermoset polymer that do not melt, and the other is thermoplastic polymer as in polyethylene used as plastic shopping bags which melt when heated. It was known that among thermoplastic polymers, crystalline polymer materials with the molecules aligned have high thermal conductivity. Professor Harada thought that the thermal conductivity of epoxy resin could be enhanced if the structure of epoxy resin was changed from an amorphous polymer chain to a regular order. To achieve this, she focused on liquid crystal, combining both the fluidity of liquid and the regularity of crystal. Beginning by designing the structure of a monomer in epoxy resin and then compounding different chemical structures to produce liquid crystal, she succeeded in generating a network polymer with strong regularity, resulting in the drastic improvement of thermal conductivity.
Conventional methods to enhance epoxy resin performance involve mixing it with various kinds of additives and fillers. Professor Harada, however, started using organic synthesis of monomers which was necessary for polymer characterization. She struggled to maintain a stable amount of polymers, and had to evaluate all sorts of polymerizing reactions because even after introducing liquid crystal into monomer structures, it was very difficult to maintain regularity. Repeating property evaluation experiments in network polymers after confirming the maintenance of regularity, she finally succeeded in developing thermally-conductive epoxy resin. Her idea of adopting liquid crystal for network polymer finally achieved success, and her research was highly acclaimed resulting in collaboration with enterprises.
Kansai University supports research through backup systems including the Organization for Research and Development of Innovative Science and Technology (ORDIST) and the Division of Community and Business Partnership for bridging corporate demands and research activities. There are many faculties which boast leading experts in each field, and have strong ties with industry. She recommends that her students participate in lectures in different fields, and also follow corporate trends. They aim to benefit society in some way, even if the fruits of their research only become obvious in the distant future.