Sulfur Analog of Spirocyclic Orthocarbonate Capable of Undergoing Tandem Double Ring-Opening Polymerization:  Synthesis, Structure, and Cationic Polymerization of Dibenzo[3,4;10,11]-1,6,8,13-tetrathiaspiro[6.6]tridecane, Property of the Polymer, and Volume Change on Polymerization

Abstract

The sulfur analog of spiroorthocarbonate (SOC) capable of undergoing tandem double ring-opening polymerization (dibenzo[3,4;10,11]-1,6,8,13-tetrathiaspiro[6.6]tridecane, 4) was synthesized, and its polymerization behavior was studied. Some properties of the polymers obtained and the volume change on polymerization of 4 were also examined. The synthesis of 4 was performed by the acid-catalyzed ester-exchange reaction of tetrakis(methylthio)methane with o-xylenedithiol and was obtained in 98% yield. The structure of 4 was determined by the spectral and elemental analysis data. Cationic polymerization of 4 with latent thermal initiator benzyl tetrahydrothiophenium hexafluoroantimonate in nitrobenzene proceeded efficiently at more than 150 °C to give the corresponding poly(thioether−trithiocarbonate) 5. The polymer structure was determined by the spectral data and further confirmed by the structures of the decomposition products formed by the reductive cleavage of the trithiocarbonate bond of 5 with LiAlH4. The mechanism of the polymerization was postulated from the results obtained. Thermal properties of 5 such as T g and T m were examined and compared with those of its oxygen analog (13). The volume change was studied in the polymerizations of 4 and its oxygen analog (2), during which 5.2 and 6.7% volume expansions were observed, respectively.

Embracing ligands. Synthesis, characterisation and the correlation between59Co NMR and ligand field parameters of Co(iii) complexes with a new class of nitrogen–thioether multidentate ligand

“…3 Xylenedithiol was prepared as described previously. 44 2,10-bis(3,3-dimethyl-2,4-dioxocyclohexanyl)-4,8-dithiaundecane (1). To a solution of sodium metal (2.13 g, 93 mmol) dissolved in dry ethanol (150 cm 3 ) was added 1,3-propanedithiol (5.00 g, 46 mmol) and the solution stirred for five minutes.…”

Non‐Shrinking Networked Materials from the Cross‐Linking Copolymerization of Spiroorthocarbonate with Bifunctional Oxetane

“…as 10%. [7][8][9][10][11][12][13] The high volume expansion may be based on the release of the very compact structures by the successive double ring-opening polymerization mode.…”

“…For example, the glass transition temperature (T g ) of poly{dibenzo [3,4,10,11]-1,6,8,13-tetraoxaspiro[6.6]tridecane} is 16 8C even though the repeating unit contains two rigid benzene rings. [8,10] The flexible nature should also reduce the internal stress in resins, although there has been less attention paid to designing no-shrink materials. Such a background encouraged us to utilize expandable SOCs as additives for the curing system of oxetanes.…”

“…For this reason, polymerizations and copolymerizations that proceed without shrinkage or with expansion in volume have been studied intensively during the last 20 years. One of the most efficient monomers for such polymerizations are spiroorthocarbonates (SOCs) whose polymerizations expand the volumes by as much as 10% 7–13. The high volume expansion may be based on the release of the very compact structures by the successive double ring‐opening polymerization mode.…”

“…Poly(SOCs) will also be effective for this purpose. For example, the glass transition temperature ( T g ) of poly{dibenzo[3,4,10,11]‐1,6,8,13‐tetraoxaspiro[6.6]tridecane} is 16 °C even though the repeating unit contains two rigid benzene rings 8,10. The flexible nature should also reduce the internal stress in resins, although there has been less attention paid to designing no‐shrink materials.…”