Vitrimers based on acrylic and vinylic polymers crosslinked via dynamic ester and amide bonds: development, processing, formulation and recycling

• Grant number: 24/16610-7
• Support Opportunities: Scholarships in Brazil - Support Program for Fixating Young Doctors
• Start date: November 01, 2024
• End date: June 30, 2025
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Watson Loh
• Grantee: Natalia Vieira Reis
• Host Institution: Instituto de Química (IQ). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 23/01427-0 - Vitrimers based on acrylic and vinylic polymers crosslinked via dynamic ester and amide bonds: development, processing, formulation and recycling, AP.R

Abstract

Vitrimers are polymeric materials that have properties similar to those of thermosets, such as dimensional, mechanical and thermal stability and insolubility. This dynamic exchange can be triggered by temperature, light or microwave, depending on the chemical groups involved in the cross-linking. The presence of dynamic reticulation nodes makes the three-dimensional polymeric network capable to reprocessing, recycling and confers the ability to self-repair (self-healing), restoring the reticulation density after the processing. Therefore, these networks are also reported as adaptive covalent networks (CAN). In this project we propose the synthesis of random copolymers of different compositions based on monomers such as glycidyl methacrylate, methyl methacrylate, styrene and dimethylacrylamide. The synthesized copolymers will be crosslinked using molecules with functionality greater than two, producing crosslinking points containing ester, ether, amine or a combination of this chemical groups, depending on the crosslinking agents used. Besides, different strategies will be explored, such as the introduction of acidic groups or Lewis bases in the carbonic chain core of polymers. The main objective of this project is to understand the influence of the composition of copolymers, the type of catalyst and its concentration, the mole fraction of crosslinkable groups and the crosslink density on the dynamics of the polymeric network and the conditions of reversibility of the crosslink points and the reticulation density which could guarantee the capacity of (re)processing and self-repair, seeking to identify and correlate possible changes in properties with chemical changes resulting from reprocessing in different conditions (reprocessing techniques, heating profiles, annealing time, etc.).