Synthesis of Biobased Block Copolymers Using A Novel Methacrylated Methyl Salicylate and Poly(3‐Hydroxybutyrate)

Abstract

A novel biobased vinyl monomer was synthesized by the reaction of methyl salicylate with methacrylic anhydride. The resulting salicylate based monomer was polymerized by reversible addition fragmentation transfer (RAFT) polymerizations using two or three trithiocarbonate functionalized poly(3‐hydroxybutyrate) macro agents. The molecular structures of the obtained polymers were confirmed by NMR spectroscopy and GPC analysis. The resulting block copolymers showed glass transition temperature (Tg) at 5 °C and melting temperature (Tm) at 160 °C according to DSC results. Compared to PHB, the obtained block copolymers displayed enhanced thermal stability according to TGA results. The overall rate constants of the RAFT polymerization using tri‐functionalized PHB macro agent were determined as 2.58 ×10−4, 1.17×10−4, and 0.50×10−4 L mol−1s−1 for 70, 80 and 90 °C, respectively. The activation energy was found to be 18.6 kcal K−1mol−1. The overall rate constant of the homopolymerization of the obtained monomer was determined as 1.14×10−4 Lmol−1s−1.

Random and Diblock Thermoresponsive Oligo(ethylene glycol)-Based Copolymers Synthesized via Photo-Induced RAFT Polymerization

“…A few earlier experiments were confusing: the molecular weight (GPC) decreased with conversion, giving the impression that the process proceeded not in a pseudo-living mode but a depolymerization mode, although the kinetic curves ( Figure 7 a) indicated the opposite: linearity was observed until the conversion of 50%. Similar phenomena were observed in [ 41 ], to a greater extent for linear polymers than for branched polymers. Experiments performed under similar conditions using monomers such as methyl methacrylate (MMA) and lauryl methacrylate (LMA) confirmed the pseudo-living nature of the polymerization: M n increased linearly with conversion ( Figure 8 ).…”

Synthesis of fully bio-based poly (3-hydroxybutyrate)-oligo-2-ethyl oxazoline conjugates

“…PHB modification reactions are important to prepare new PHB derivatives for some industrial and medical applications ( Hazer, 2010 ; Hazer et al, 2012 ; Guennec et al, 2021 ). Some of them are halide derivatives ( Arkin and Hazer, 2002 ; Yalcin et al, 2006 ; Erol et al, 2020 ), chitosan derivatives ( Arslan et al, 2007 ), diethanol amine derivatives ( Tuzen et al, 2016 ), trithiocarbonate derivatives ( Hazer et al, 2020 ), methyl salicylate derivatives ( Hazer et al, 2021 ), ricinoleic acid derivatives ( Ullah et al, 2024 ), PEG derivatives ( Hazer et al, 1999 ; Wadhwa et al, 2014 ), and caffeic acid derivatives ( Abdelmalek et al, 2023 ).…”