Zinc diethyldithiocarbamate as a catalyst for synthesising biomedically-relevant thermogelling polyurethanes
| Autor: | Qianyu Lin, Liangfeng Guo, Kun Xue, Jason Y. C. Lim, Xian Jun Loh, Connie K. Liu |
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| Rok vydání: | 2020 |
| Předmět: |
chemistry.chemical_classification
Vulcanization chemistry.chemical_element 02 engineering and technology Polymer Zinc 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Catalysis law.invention Dibutyltin dilaurate Polyester chemistry.chemical_compound chemistry Polymerization Chemistry (miscellaneous) law Organic chemistry General Materials Science 0210 nano-technology Polyurethane |
| Zdroj: | Materials Advances. 1:3221-3232 |
| ISSN: | 2633-5409 |
| DOI: | 10.1039/d0ma00734j |
| Popis: | Zinc dithiocarbamates are traditionally highly-efficient catalysts for accelerating rubber vulcanization reactions, but have thus far not found substantial use in other forms of polymerisations. Herein, we demonstrate a new application of zinc diethyldithiocarbamate (ZDTC) for the synthesis of polyurethanes suitable for biomedical applications. Compared with other organozinc compounds such as zinc acetylacetonate and zinc neodecanoate, ZDTC showed exceptional catalytic performance, capable of forming high molecular weight polyurethanes, with the reaction tolerant to different organic solvents. The ZDTC-catalysed biocompatible amphiphilic polyurethanes comprising PEG and PPG blocks form thermo-responsive hydrogels which showed remarkably low sol-to-gel transition temperatures at surprisingly low concentrations in water. Microstructural analysis of the polyurethane aqueous solutions by small-angle X-ray scattering (SAXS) experiments revealed considerable supramolecular self-assembly of the polyurethanes even at 4 °C. Valuably, cell viability studies revealed that residual ZDTC catalysts present in unpurified polyurethane polymers exerted considerably lower cytotoxicities than those catalysed by tin(IV) catalysts such as dibutyltin dilaurate (DBTL). As demonstrated herein, ZDTC may be a possible alternative to highly-toxic organotin catalysts for the synthesis of polyurethanes, with further potential for other polymerization reactions reliant on organotin Lewis acidity such as polyester synthesis. |
| Databáze: | OpenAIRE |
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