Synthesis and characterization of hydrolyzed polyoxazolines and investigation of their curing capabilities

Official URL: https://www.eurasianbiochem.org/bildiri%20taslaklar%C4%B1/Proceeding_Book_EurasianBioChem_2022.pdf

Polyoxazoline (POZ) polymers have been gaining ground vastly recently with expanding application range from drug delivery systems to biosensors. This is due to the remarkable tunability and flexibility that these polymers offer in terms of ease of synthesis, thermal properties, hydrophilicity, hydrophobicity and functional groups. Polyoxazoline-Polyethyleneimine (POZ-PEI) copolymers, resulting from hydrolysis of POZ polymers, show curing capabilities with adjustable curing temperature. These make this family of polymers a suitable candidate for use in one-component epoxy resin systems as thermal latent curing agents where both shelf-life and controlled curing temperature are a defining character. In this article, POZ-PEI based curing agents were synthesized as thermal latent curing agents for one-component epoxy resin systems. In the first step, different POZ polymers with alkyl/aryl pendant groups were synthesized and then hydrolyzed to result in POZ-PEI copolymers with preferred compositions. 1H-NMR, FTIR, GPC, TGA and DSC analyses were used to determine the structural and thermal characteristics of the prepared polymers and following copolymers. Also, for curing studies, DGEBA was chosen as the epoxy resin and DSC analysis was used to determine the curing behavior of curing agent-epoxy resin systems. We investigated the kinetics of POZ hydrolysis to fine-tune the composition of the POZ-PEI copolymers. In addition, the effect of the molecular weight, composition and side chain groups on the curing behavior of epoxy resin systems was studied.