Poly[1-(trimethylsilyl)-1-propyne] and related polymers: synthesis, properties and functions

Since the first report of the synthesis of poly[1-(trimethylsilyl)-1-propyne] [poly(TMSP)] in 1983, a large number of publications, presently up to about 350 journal articles and patents, has appeared due to its unique structure and properties and, in particular, its extremely high gas permeability. This review article surveys the synthesis, properties, and functions of poly(TMSP) and related polymers. Investigations of all aspects of this polymer are introduced: journal articles are cited comprehensively, and important patents are included. Poly(TMSP) can be obtained by metathesis polymerization of 1-(trimethylsilyl)-1-propyne by TaCl5 and NbCl5. This polymer is characterized by high molecular weight (up to around one million), good solubility in many common solvents (e.g. toluene and chloroform), formation of tough films by solution casting, a high glass transition temperature (>250°C), and fair thermal stability. Its oxygen permeability at 25°C is ca. 6×10−7 cm3(STP)cm/(cm2 s cmHg), which is the highest value of all existing polymers. The gas permeation properties of poly(TMSP) have been intensively studied, especially with regard to various permeation mechanisms. Various modifications of poly(TMSP) have also been examined to improve its gas separation performance. Other applications which have been investigated for poly(TMSP) include pervaporation (as an ethanol–water separation membrane), sensors, and photoresists.