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Unraveling substituent effects on the glass transition temperatures of biorenewable polyesters.

ABSTRACT: 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 (T_g 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 T_g 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 methyl-induced 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.

SUBMITTER: Yu X

PROVIDER: S-EPMC6056526 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Unraveling substituent effects on the glass transition temperatures of biorenewable polyesters.

Yu Xiaopeng X Jia Junteng J Xu Shu S Lao Ka Un KU Sanford Maria J MJ Ramakrishnan Ramesh K RK Nazarenko Sergei I SI Hoye Thomas R TR Coates Geoffrey W GW DiStasio Robert A RA

Nature communications 20180723 1

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 (T<sub>g</sub> 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 polyme ...[more]

PMID: 30038298

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Unraveling substituent effects on the glass transition temperatures of biorenewable polyesters.

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Unraveling substituent effects on the glass transition temperatures of biorenewable polyesters.

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