(407a) Manufacture of Value-Added Products By Ozonolysis From Soybean Oil

The depletion of non-renewable resources by modern societies and the need for a sustainable chemical industry are major factors that contribute to an increasing interest to study and develop new biobased polymers. The generation of biobased building blocks for polymer synthesis is a primary research topic towards this goal. Soybean oil is a widely available resource, relatively cheap and contains the structure of unsaturated fatty acids, which can be modified into polymer building blocks by either (1) functionalization of these unsaturated fatty acids or (2) cutting them into small molecules while adding useful functional groups (e.g. carboxyl, hydroxyl, formyl, etc.).  In this project, we will focus on the latter strategy by breaking the double bonds present in unsaturated fatty acids via ozonolysis. Ozone is known to be a very strong oxidant, capable of reacting with alkenes and breaking double bounds to generate formyl and carboxyl groups.

Advantages of using ozonolysis for oxidizing fatty acid double bonds include fast reaction rates and the low footprint of this chemical in the final product mixture. However, there are also some disadvantages that include the formation of a wide range of by-products, some of which are unstable compounds (e.g. ozonides). Moreover, ozonolysis reactions occur in a gas-liquid interface, which become hard to study and to measure the reaction kinetics. 

In this work we will evaluate two solvent systems to perform ozonolysis reactions. In one case we utilized methanol as a solvent system to generate methyl-monoesters and -diesters, which can be utilized as polymer building blocks (e.g. polyesters). In a second case, we will utilize water as the ozonolysis solvent which allows the generation of aldehydes with yields ranging 75-77% in the best scenario. Some of these aldehydes (e.g. hexanal and nonanal) can be utilized as bio-based polymer building blocks. The kinetics of ozonolysis reactions will be studied as a function of reaction temperature, time and reactants concentration. A kinetic model will be elaborated as a function of these variables, and kinetic parameters will be determined by fitting the model equation to our experimental data through regression.

Purified aldehydes from the aqueous ozonolysis system, such as hexanal and nonanal, will be utilized in the synthesis of new biobased acetal polymers. Structural and performance characterization of these new biobased polymers will be performed to evaluate their potential areas of utilization and respective target markets.