Synthesis and characterization of siloxane functionalized CO2-based polycarbonate

CO2-based polycarbonates are among the most promising eco-friendly polymers with excellent biodegradability and biocompatibility. However, the poor perfor-mance of conventional CO2-based polycarbonates such as poly(propylene carbonate) (PPC) and poly(cyclohexene oxide) (PCHC) limits their application. Herein, a series of siloxane functionalized CO2-based polycarbonates were obtained via terpolymerization of carbon dioxide (CO2), propylene oxide (PO), and [2-(3, 4-epox-ycyclohexyl)-ethyl] trimethoxysilane (TMSO) using a SalenCoCl/PPNCl catalyst system. A systematic study of these polycarbonate's thermal, mechanical, and surface properties was conducted by tuning the ratio between TMSO and PO. The siloxane units offered polycarbonate with a higher surface energy, resulting in a water contact angle of 110 degrees and a significant improvement in glass transition temperature (Tg) and decomposition temperature (Td). Additionally, the micro-crosslinked structure formed by the hydrolysis and condensation of methoxysilane groups provided to the polycarbonate's remarkable mechanical strength, with a high tensile strength of 46 MPa. As a result, a novel CO2-based polycarbonate derived from cost-efficient silane coupling agents and CO2 has shown promising results as an alternative to rigid plastics used in industry.

Automated summary

Siloxane functionalized CO2-based polycarbonates were synthesized via terpolymerization of CO2, PO, and TMSO using a SalenCoCl/PPNCl catalyst system. By adjusting the ratio between TMSO and PO, the polycarbonates exhibited improved thermal, mechanical, and surface properties. The introduction of siloxane units increased the surface energy, leading to a water contact angle of 110 degrees. The micro-crosslinked structure formed by the hydrolysis and condensation of methoxysilane groups enhanced the mechanical strength.