Unraveling Substituent Effects on the Glass Transition Temperatures of Biorenewable Polyesters
Polymers and High Performance Materials
Converting biomass-based feedstocks into polymers not only reduces our reliance on fossil fuels, but also furnishes multiple opportunities to design biorenewable polymers with targeted properties and functionalities. Here we report a series of high glass transition temperature (Tg up to 184 °C) polyesters derived from sugar-based furan derivatives as well as a joint experimental and theoretical study of substituent effects on their thermal properties. Surprisingly, we find that polymers with moderate steric hindrance exhibit the highest Tg values. Through a detailed Ramachandran-type analysis of the rotational flexibility of the polymer backbone, we find that additional steric hindrance does not necessarily increase chain stiffness in these polyesters. We attribute this interesting structure-property relationship to a complex interplay between methylinduced steric strain and the concerted rotations along the polymer backbone. We believe that our findings provide key insight into the relationship between structure and thermal properties across a range of synthetic polymers.
Sanford, M. J.,
Ramakrishnan, R. K.,
Nazarenko, S. I.,
Hoye, T. R.,
Coates, G. W.,
DiStasio, R. A.
(2018). Unraveling Substituent Effects on the Glass Transition Temperatures of Biorenewable Polyesters. Nature Communications, 9, 1-9.
Available at: https://aquila.usm.edu/fac_pubs/15371