I want to thank the Iowa State Daily for covering our research on the development of soybean oil plastics in the Wednesday, Jan. 30 (“Soy plastics dampen appliance noise”). However, I would like to correct some serious errors and misquotes in that article. The article indicated that we are only using “a relatively low amount” of soybean oil in the plastics and that we are trying to increase the amount of oil used from 40 to 65 percent. In fact, our new soy plastics are made of substantial amounts of soybean oil, anywhere from 40 to 65 weight percent typically. With the lower amounts of soybean oil, we get tough, hard plastics. With the larger amounts, we get rubbery, elastomeric materials. There are very substantial industrial markets for both types of materials.

One of the very attractive features of these novel, new plastics is the fact that they use large amounts of a naturally-occurring, cheap, environmentally-benign starting material, soybean oil, that replaces increasingly expensive and dwindling supplies of petroleum-based materials. The other comonomers used in our plastics are styrene and divinylbenzene, which are petrochemicals used all the time in today’s plastics industry, but they cost substantially more than soybean oil. Our soy plastics appear to be exceptional at dampening sound and vibrations, as well as shape memory applications. Shape memory plastics return to a previously determined shape upon simply heating the material. Few petroleum-based plastics possess either of these attractive properties.

Finally, I wish to acknowledge the generous support of the Iowa Soybean Promotion Board and my terrific collaborators on this project, Dr. Fengkui Li, who has directed the laboratory work and Professor Valerie Sheares, who has served as an invaluable consultant.

Richard C. Larock

University professor of chemistry