Rapidly-cured isosorbide-based cross-linked polycarbonate elastomers

The rapid synthesis of an optically-transparent, flexible elastomer was performed utilizing the naturally-derived source, isosorbide. A novel monomer based on isosorbide (isosorbide dialloc, IDA) was prepared by installing carbonate functionalities along with external olefins for use in thiolene click chemistry. Cross-linked networks were created using the commercially-available cross-linker, trimethylolpropane tris(3-mercaptopropionate) (TMPTMP) and resulted in IDA- co -TMPTMP, an optically-transparent elastomer. Systematically, IDA- co -TMPTMP networks were synthesized using a photoinitiator, a UV cure time of one minute and varied post cure times (024 h, 125 mm Hg) at 100 C to observe effects on mechanical, thermal and surface alterations. The mechanical properties also had limited changes with post cure time, including a modulus at 25 C of 1.92.8 MPa and an elongation of 220344%. The thermal decomposition temperatures of the networks were consistent, ca. 320 C, while the glass transition temperature remained below room temperature for all samples. A cell viability assay and fluorescence imaging with adherent cells are also reported in this study to show the potential of the material as a biomedical substrate. A degradation study for 60 days resulted in 8.3 3.5% and 97.7 0.3% mass remaining under accelerated (1 M NaOH, 60 C) and biological conditions (pH 7.4 PBS at 37 C), respectively. This quickly-synthesized material has the potential to hydrolytically degrade into biologically-benign and environmentally-friendly by-products and may be utilized in renewable plastics and/or bioelastomer applications. The natural compound, isosorbide has been functionalized and rapidly cross-linked using thiolene click chemistry to afford an optically-transparent, flexible elastomer.