(56e) Effect of Butyl Glycidyl Ether Model Co-Monomer on Poly (glycerol succinate) Network and Dynamics for the Design of Multifunctional Hyperbranched Polymers

An original approach has been developed to easily design functional materials from poly (glycerol succinate) (PGS). This strategy is related to the introduction of an epoxidized functional agent during the polyesterification between the glycerol and succinic acid. The impact of this epoxide group on the polymerization chemistry and its hyperbranched network has been modeled by using the butyl glycidyl ether (BGE) as co-monomer. The potential reactions have been confronted with the units topology revealed by 2D NMR correlations. The regioselectivity and the stoichiometry of the system were modified in situ by the kinetic control of parallel reactions. As a result, we observed a delay of the gelation and an increase of the polyesterification conversion. The resulting hyperbranched polymers (HBPs) obtained just after gelation present a temperature of glass transition (T_g) of -3.9 ºC for PGS and -16.1 ºC for Poly(glycerol-co-butyl glycidyl ether) succinate (PGS-co-BGE). This difference was related to the dynamic motion of the BGE butyl tails which play the role of spacer between the polymer chains during the relaxation process. The dependency of the effective activation energy (E_α) through the T_g was calculated by using the advanced isoconversional method. The variation of E_α was associated to a competition between the cooperative chains motions and the sequestration effect of the hydrogen bonds. This behavior can be potentially generalizable to the plastic glass containing a critical amount of secondary interactions.

Acknowledgment: This research is financially supported by (1) the Ontario Ministry of Agriculture, Food, and Rural Affairs (OMAFRA)-New Directions Research Program (Project # 050155); and (2) OMAFRA-University of Guelph Bioeconomy-Industrial Uses Theme (Project # 200283).