Hung Chien Lin

What is the biggest challenge in designing polyesters?

Making a monoester is not complicated. The reaction is very straightforward, a condensation reaction between a carboxylic acid and an alcohol. The problem is in making the polyester. The principle is the same, but you’re making a bigger molecule. That also means that there are many more carboxylic acid and alcohol groups available to perform that condensation reaction. There are many options, so it is hard to control which groups will react and which will not. For an ester, it is quite straightforward – a condensation reaction of carboxylic acid and alcohols. But polyesters, the principle is the same, but the molecule has multiple carboxylic acids and multiple hydroxy group so there are multiple condensation reactions that can happen. That means you can get unwanted side products, for example. Unwanted side products also can affect the strength of the final product in mixture. The conditions in which the polyester is now made, sometimes change the color of the product, which is very much unwanted in the coating industry.

What is the long term goal of your research?

I want to make a polymer that can be applied to use as a coating. These polymers are already made in industry, but the methods use a lot of energy. That’s why we want to design an environmentally friendly catalyst that can make the reaction to occur at a lower temperature. That is more sustainable, but also could allow for other starting materials to be used. Some starting materials are not stable at the high temperature some coatings are now made. With the use of a catalyst, more materials can be used, which also opens up more possibilities to use sustainable starting materials.

What is your short term goal? What do you want to solve in the coming three years?

The goal is definitely to see the catalyst we’re developing being comparable to the current method. I think it is possible to have that in three years’ time. We still need to think about the systems that can work. Now we are also thinking about different aspects to do analysis on, and maybe after analyzing we have the way to make the catalyst better.

I’m mainly working on the first stage of developing this catalyst. The differences between lab and industry are very big. The scale and the content are different. What we do in the lab is probably not favorable in industry: we have elaborate equipment and setups. That is why a team within AkzoNobel will use the catalyst we developed and make it suitable for use in industry.