Opening up new possibilities in polymer research

Among the many fields of science, polymer research is the one most closely related to our daily lives. The closest of all polymers are the plastics used in packaging containers and vinyl, and the synthetic fibers and fabrics used to make clothes. There are so many different polymers and, consequently, so many research fields that the list is endless.
“The fact that there is a lot of ongoing research also means that it is difficult to make brand-new discoveries. Eventually, we researchers wonder what we can do to advance further from the existing research on polymers.”
Instead, Professor Koo is deriving new results with a differentiated research method involving the use of an emulsion tool that can handle not only polymers but also soft materials, including liquid crystals and colloids. This enables Professor Koo to adopt a three-dimensional approach and derive flexible changes.
"Emulsion refers to the state in which one liquid is colloidally dispersed in another liquid, like milk. While two liquids that generally do not mix form a boundary, we can make them completely miscible. They can also be separated again over time. We are conducting research aimed at eliciting various property changes in polymers using these flexible characteristics.” As well as recognizing Professor Koo’s development of a novel polymer structure, the 21st L'Oréal Korea-UNESCO Women’s Scientist Award recognized the results of her use of the emulsion tool. Professor Koo's team has developed a sensor that detects changes in the properties of a polymer. This sensor is a technology that can detect changes in structural color (color caused by interference effects due to the absorption, reflection, and transmission of light) by external stimuli such as light or temperature or changes in color that occur during the biodegradation process of biodegradable polymers. Professor Koo’s team is further developing the research into a technology that can control changes beyond simply detecting color changes.
“We are also developing materials by changing the structures of polymers. My research team has succeeded in developing particles that exhibit independent optical properties by applying a polymer with a novel elongated structure to an emulsion tool. The particles change color according to rotation or directionality, thanks to their elongated shapes. Even if they do not contain pigments like the structural colors of animals and plants, they can change color depending on how the direction is controlled. Therefore, there is no photofading (color fading), and we can express color according to the desired performance.
This technology will likely be used in such areas as intelligent window painting. Just as blinds can block the transmission of light by adjusting the direction, it is possible to change colors in various ways by regulating the particles. Professor Koo’s research team plans to deepen its research on particle control methods and expand the scope of their application at actual industrial sites.

Aspiring to become a growing scientist and a wise leader

Until now, research has mainly been focused on color change, but Professor Koo hopes to open up more diverse possibilities for polymers by studying various interfaces in the future. Among them, her team is also paying attention to biodegradable polymers. Replacing environmentally hazardous materials such as plastics with biodegradable materials is also a trend of the times.
“Polymers are just materials, and it is essential to pay attention to the phenomenon at a certain interface (i.e. the interface between two adjacent phases of the three phases such as the gas phase, liquid phase, and solid phase). Cosmetics such as cushions and foundations are also made using changes in the interface. “L’Oréal Korea has paid attention to my team’s research because there are many areas where the method and direction of research can be linked to the cosmetics industry.”
Professor Koo's view, however, is wider than this. She anticipates that joint research with other fields and industry-academia cooperation will become more active because interface research is more in-depth.
“I joined UNIST in February of this year, and even though I’ve only been here for a short period, I can see how dedicated this place is to research. I am very impressed with how well the research environment is equipped, as it enables me to do as much research as I wish, and the fact that joint research is being carried out very widely. I also actively engage in joint research with other professors in various fields.”
If Professor Koo’s goal as a scientist is to immerse herself in her chosen field of research, develop new technologies, and grow, then her goal as an educator or a leader of a research team is to become a wise person. She wants to be a supporter who can make wise judgments in situations facing students.
“I also thought a lot about my career path when I was a student. At that time, I received help from my advisor. I want to be a leader who could bring knowledge and experience to, and relieve the worries of, my team members.
Professor Koo is not only a budding scientist who needs to immerse herself in research but also the mother of a 9-month-old baby. Although striking a sound balance between her home life and work may not be easy, she has expressed her desire to be a scientist and a woman who can set a strong example for her juniors. As a scientist, leader, and mother, she takes clear steps forward without any hesitation.

• “I want to become a leader who can transmit my knowledge and experience to my students while alleviating their worries and concerns.”
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