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  1. null (Ed.)
  2. Honokiol, a highly functional phenolic- and alkenyl-containing neolignan natural product isolated from several Magnolia plant species, is an interesting bio-based resource, which is shown to be useful directly as a monomer for the rapid and scalable synthesis of poly(honokiol carbonate) (PHC). PHC was synthesized in one step from the natural product using condensation polymerization methods. Polymers of number average molecular weight ( M n ) ranging from 10–55 kDa were obtained on gram scales in yields up to 80%. Thermal analysis demonstrated high thermal stability, with degradation temperatures in excess of ca. 450 °C. Mechanical testing of several PHC polymers indicated a generally increasing storage modulus with increasing M n and a similar trend with T g . With an interest toward cardiovascular applications, initial cytotoxicity and fluorescence cell imaging studies were conducted and showed no cytotoxicity toward coronary venular endothelial cells (CVECs), which proliferated on PHC thin films up to a month. Bulk PHC is a robust material, as it underwent slow hydrolytic degradation under basic conditions ( ca. 0.1% per day under 1 M NaOH (aq) ), and no observable degradation under acidic and neutral conditions, each at 37 °C over 130 days. These polycarbonates serve as potential specialty engineering- or bio-materials derived from a commercially-available natural product monomer. 
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  3. 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 thiol–ene 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 (0–24 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 1.9–2.8 MPa and an elongation of 220–344%. 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. 
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