Lignin is a plant-derived biopolymer that is the main byproduct of paper and cellulosic ethanol production. While >100 million tons are generated annually, only a small fraction finds technological application. In plants, lignin acts as a binder between cellulose fibers, so it has natural interfacial functionality. The Washburn Lab at CMU has developed a strategy for preparing high-performance surfactants based on a lignin core grafted with water-soluble polymers. The I-Corps team will be focused on exploring applications of these lignin surfactants in delivering herbicides used in agriculture. Many herbicides have low solubility in water, and a broad range of chemicals is used to apply them in the field. However, many of these chemicals are toxic and persistent in the environment. In addition to being based on a renewable resource, lignin-based surfactants are biocompatible and biodegradable, making them a potentially high-impact chemical technology in agricultural applications.
This I-Corps team is exploring applications of this technology as an adjuvant for the delivery of agrochemicals. The combination of reducing surface tension, low solution viscosity, and strong affinity for aromatic compounds that are common herbicides make these an attractive candidate from a performance perspective, and the intrinsic natural biodegradability and lack of toxicity could address many of issues facing the current generation of surfactants used in agriculture. However, agrochemical adjuvants represent a complex class of chemicals, and it will be critical to interview experts in chemical companies that make other adjuvants, formulations companies that sell directly to farmers, and end-users to understand better their needs. In addition, preliminary pilot-scale manufacturing will be performed to prepare kilogram quantities of materials for field tests and to assess variables such as coupling efficiency and kraft lignin source on the properties of the final product.
