Senior Project Advisor

John Misasi

Document Type


Publication Date

Spring 2021


ocean, plastic, recycling


The following report summarizes the research performed for the project sponsored by Net Your Problem. The research focuses on using depolymerization reactions as a method of separating polyester from polyolefin material in braided lines commonly used in the fishing and crabbing industries. Currently the mixed fibers in these lines are too comingled to be separated by conventional mechanical recycling methods. The glycolysis reactions were chosen to take advantage of the very different solubilities of polyester and polyolefins. Ethelene glycol breaks down the PET into oligomers and BHET monomer while leaving the polyolefins unreacted. The products of the reaction can then be poured into water which solubilizes the polyester material and leaves the polyolefins floating on the surface. Two glycolysis reactions were performed over the course of this research. The first was in a 2L batch reactor with no catalyst and the second was in a smaller round bottom flask with 5 mass% NaOH catalyst to polyester. DSC was used to quantify polyester and polyolefin content in the lines and products of the reaction. TGA was used to quantify contaminants and identify oligomeric polyester in the products. FTIR was used to identify functional groups of polyester, polyolefins and solvents in the products. The primary goal of this research is to develop a method of separating the polyester and polyolefins so that there is less than 5% contamination in each material, allowing them to be recycled. If the contamination metric is reached by this process, the oligomeric polyester and BHET that was formed could be resynthesized into virgin polyester, and polyolefin material could be processed into a new product. Ideally these materials will be used to create products used in the fishing industry to incentivize fishermen to recycle their derelict fishing gear.


Advanced Materials Science and Engineering Center

Subjects - Topical (LCSH)

Fishing lines--Recycling; Polyesters--Separation; Oligomers--Mixing; Plastics in fisheries


fieldwork (research)




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