Synthesis and characterization of polymeric linoleic acid graft copolymers using atom transfer radical polymerization

Abstract

Linoleic acid modified through autoxidation, hydroxylation, and bromination was utilized for the first time in controlled/living radical polymerization methods such as atom transfer radical polymerization (ATRP). A brominated polymeric linoleic acid macromonomer initiator (ATRP–MIM) was synthesized as a macromolecular initiator (MIM) based on polymeric linoleic acid for use in ATRP. Using this ATRP–MIM and styrene monomer, novel graft copolymers were successfully synthesized via ATRP. The effects of various reaction parameters, including monomer concentration, initiator concentration, and polymerization kinetics, were systematically investigated. Additionally, the impact of reaction conditions on molecular weight and polydispersity was studied. The percentage compositions of the structural contents of graft copolymers were determined using ¹H NMR. Detailed characterization, including structural analysis, thermal properties, and molecular weight determination, was performed using techniques such as Fourier-transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The obtained graft copolymers exhibited enhanced thermal stability and well-defined molecular structures, contributing to the development of bio-based polymeric materials with specialized properties for applications in coatings, biocompatible systems, and advanced functional materials.

Graphical abstract

This study introduces the use of modified linoleic acid, altered through autoxidation, hydroxylation, and bromination, in controlled radical polymerization methods such as atom transfer radical polymerization (ATRP) for the first time. The research focuses on the synthesis of graft copolymers by using a brominated polymeric linoleic acid initiator (ATRP-MIM) in copolymerization with styrene.