A novel approach for anionic bulk polymerization of 1,3,5‐tris(trifluoropropylmethyl)cyclotrisiloxane

Abstract

Present work gave a new method for preparing polymethyl(3,3,3‐trifluoropropyl)siloxane (PMTFPS) in the mixing chamber of a torque rheometer using sodium silanolate as initiator, and ethyl acetate (EA) and dimethyl sulfoxide (DMSO) as promoters. The promoting effect of EA in the anionic bulk polymerization of 1,3,5‐tris(trifluoropropylmethyl) cyclotrisiloxane (F3) was investigated in comparison with DMSO, a common promoter. Results showed that EA exhibited an effective promoting effect as DMSO did. When the polymerization was carried out for 4.0 min at 120°C in the presence of 0.30 mol L−1 EA, the maximum of number average molecular weight (Mn = 2.45 × 105 g mol−1) of PMTFPS was obtained with high yield (89.2 wt%). The back‐biting reactions during the polymerization were almost suppressed and less than 0.75 wt% cyclic by‐products were obtained by matrix‐assisted laser desorption ionization time‐of‐flight mass spectrometry (MALDI‐TOF‐MS) for EA promoter system. Investigations of differential scanning calorimetry and thermogravimetic analysis showed that PMTFPS could be used in a wide range of operational temperatures. POLYM. ENG. SCI., 2010. © 2010 Society of Plastics Engineers

Improved synthesis and properties of hydroxyl‐terminated liquid fluorosilicone

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“…Among many possible fluoro‐substituted diorganopolysiloxane compositions, the hydroxyl‐terminated poly(trifluoropropylmethyl)siloxane (PTFPMS‐OH) fluids are especially valuable. PTFPMS‐OH is usually used to prepare room‐temperature vulcanized PTFPMS rubber, and in general, it is synthesized by the ring‐opening polymerization of D 3 F …”

The effect of ceria nanoparticles on improving heat resistant properties of fluorosilicone rubber

“…Those two mechanisms are suitable for the PTFPMS. 28 However, in air, the oxidation scission happened along with the siloxane rearrangement. The PTFPMS was completely deteriorated into cyclic oligmers and volatilized, leaving a slight residues.…”

Synthesis of gradient copolysiloxanes by simultaneous copolymerization of cyclotrisiloxanes and mechanism for kinetics inverse between anionic and cationic ring‐opening polymerization

“…Polysiloxanes are important inorganic/organic materials possessing unique set of properties that make them useful in numerous applications . Siloxane chains present in polysiloxanes exhibit unusual static flexibility which in combination with low intermolecular forces leads to exceptionally low glass transition temperatures ( T g ) and small viscosity changes with temperature of polysiloxanes .…”

“…INTRODUCTION Polysiloxanes are important inorganic/ organic materials possessing unique set of properties that make them useful in numerous applications. [1][2][3][4][5][6][7] Siloxane chains present in polysiloxanes exhibit unusual static flexibility which in combination with low intermolecular forces leads to exceptionally low glass transition temperatures (T g ) and small viscosity changes with temperature of polysiloxanes. [8][9][10][11] Incorporation of polysiloxane segments into common organic polymers or different types of polysiloxane segments lead to the fabrication of the copolymers.…”