Polyphosphazene Elastomers with Alkoxy and Trifluoroethoxy Side Groups
Zhongjing Li, Chen Chen, Mitchell McCaffrey, Hui Yang, Harry R. Allcock
Abstract
Elastomers based on the polyphosphazene skeletal platform are the subject of broad interest from both biomedical and technological viewpoints. Here, we describe a fourth generation of polyphosphazene elastomers with both 2,2,2-trifluoroethoxy (CF3CH2O−) and nonfluorinated alkoxy groups such as CH3CH2O–, CH3CH2CH2O–, or CH3CH2CH2CH2O– units. These structures provided access to elastomers with very low glass transition temperatures in the range of −60 to −90 °C. Variations in the relative percentages of the alkoxy and trifluoroethoxy side groups have a significant influence on the physical properties, which were studied by stress–strain, differential scanning calorimetry, and thermogravimetric analysis techniques. Biomedical materials focused on cardiovascular and dental applications are target applications.