Kinetic study of thiol-ene step-growth photopolymerization of limonene with bifunctional thiols

• Grant number: 25/13734-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2025
• End date: August 31, 2026
• Field of knowledge: Engineering - Chemical Engineering - Chemical Technology
• Principal Investigator: Roniérik Pioli Vieira
• Grantee: Alice Junqueira de Souza
• Host Institution: Faculdade de Engenharia Química (FEQ). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 22/02728-0 - Development of films and hydrogels containing terpenes or derivative oligomers for active packaging and multifunctional medical devices applications, AP.PNGP.PI

Abstract

Limonene (LIM) is a monoterpene primarily found in citrus peels, with significant potential as a renewable monomer for polymer production or as an additive in plastics, owing to its antioxidant and antimicrobial properties. However, its high volatility poses challenges for incorporation into polymeric materials. A promising approach to address this issue is thiol-ene step-growth photopolymerization, which stabilizes LIM by producing oligomers with various structural properties, simply by altering the employed thiol. This flexibility allows the creation of a wide range of bio-based polymers with customizable features. Herein, we will explore the kinetics of thiol-ene photopolymerization of LIM with bifunctional thiols, such as butane-1,4-dithiol, hexane-1,6-dithiol, and 2,2'-(ethylenedioxy)diethanethiol, to synthesize poly(thioethers). A kinetic model will be developed and fitted to experimental data, and numerical simulations will predict the conversion of monomers and the molecular weight of the resulting polymers under varying reaction conditions. This research aims to provide valuable insights into the photopolymerization of LIM and contribute to the development of sustainable, limonene-based poly(thioether) materials for applications in biomedicine, food packaging, and beyond.