Two disiloxane compounds, 3,3′-(1,3-dimethyl-1,3-diphenyl-1,3-disiloxanediyl)bis(benzenamine) (C1) and 4,4′-(1,3-dimethyl-1,3-diphenyl-1,3-disiloxanediyl)bis(benzenamine) (C2) were synthesized and used as new curing agents of DGEBA epoxy resin with an epoxy value of 0.51 (E-51). The curing kinetics of E-51/C1 and E-51/C2 systems was investigated by non-isothermal differential scanning calorimetry (DSC) analyses. The activation energy (ΔE) and the characteristic cure temperatures of the two systems were determined. The two systems have the similar activation energy. The reactivity of E-51/C1 is higher than that of E-51/C2. The reaction orders of E-51/C1 and E-51/C2 are 0.88 and 0.87, respectively, illustrating that curing reaction between the epoxy resin and curing agent (C1 or C2) is complicated. The DSC result shows that E51 cured by C2 has higher Tg; whereas thermogravimetric analysis results indicate that E51 cured by C1 has higher thermal stability. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42385.

A series of liquid polycarbosilanes were successfully synthesized by a sequential Grignard coupling reaction of (chloromethyl)triethoxysilane and vinylmagnesium bromide, followed by reduction with lithium aluminium hydride. The use of non-corrosive, easily handleable and storage stable (chloromethyl)triethoxysilane as starting material is an attractive advantage for this route. The as-synthesized polymers containing Si−CH=CH₂ and Si − H groups are storage stable and can be easily cured in an inert atmosphere. The ceramic yield of the cured polycarbosilane and the C:Si ratio of the derived ceramic were varied by adjusting the mole ratio of starting materials in the feed. Among them, the polymer with a mole ratio of Si−CH=CH₂ to Si − H of 1:10 has the highest ceramic yield at 89.6% after curing at 220 °C and the C:Si ratio of the derived ceramic is 1.48. This kind of polycarbosilane shows high potential as an SiC ceramic precursor in the fabrication of an SiC matrix by the precursor infiltration pyrolysis process. © 2015 Society of Chemical Industry

Silicon oxynitride coatings on glass and polyethylene terephthalate (PET) film have been fabricated by thermal annealing of inorganic polymer perhydropolysilazane (PHPS) between 60 °C and 200 °C. The chemical structure, thermal behavior and structural evolution of PHPS were investigated. The coatings obtained on glass possess pencil hardness as high as 9H, high transparency above 90% in the visible wavelength range, good adhesion to the substrate and a hydrophobic property with water contact angle above 98°. The PHPS coated PET film has pencil hardness above 4H, water contact angle 102° and a high scratch resistance property with no obvious scratches after a 50 cycles scratch test under a load of 2 kg. All these data imply the great potential of PHPS as a hard coating for optical devices. © 2015 Society of Chemical Industry

A facile synthetic route was developed to fuse furan rings to a dibenzosilole core for the construction of difurobenzosilole derivatives through an electrophilic double cyclization reaction. Only silafluorene derivatives with electron-donating groups on the periphery participated in this cyclization. Suzuki–Miyaura coupling and deiodination of the diiododifurobenzosiloles resulted in highly emissive silicon-bridged dibenzofuran compounds. These obtained compounds exhibited very high luminescent quantum yields (93 to about 99 %) and good thermal stability. Single crystals of the silicon-bridged dibenzofuran compound with a marginal phenyl group were easily grown and analyzed by single-crystal X-ray diffraction, whereas the deiodinated silicon-bridged dibenzofuran compound showed a high tendency to self-organize into 1D microfibers in various solvents such as hexane, toluene, and THF.

A series of silicon-containing self-catalyzed phthalonitrile derivatives (SiPNs) have been successfully synthesized from reaction of 4-(4-aminophenoxy)phthalonitrile (APN) with corresponding chlorosilanes. The chemical structures of the SiPNs were confirmed by spectroscopic techniques. The introduction of silicon-containing unit into the phthalonitrile structure has dramatically decreased the melting point from 143°C for APN to 40–60°C for the new SiPNs, which also exhibit improved solubility and are soluble in many common solvents. Differential scanning calorimetry analysis showed that they possess the self-catalyzed behavior with the temperature of exothermic peak due to the self-catalyzed reaction between 255 and 281°C. The cured SiPNs exhibit excellent thermal stability with glass transition temperature above 450°C, the temperature of 5% weight loss in range of 535–570°C under nitrogen, and 543–562°C under air. Their char yields at 1000°C are in the range of 80.2–82.6% in nitrogen, and 10.1–12.5% in air, respectively. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40919.

A new polymeric precursor, perhydropolysiloxazane (PSNO), for silicon oxynitride (SiON) ceramic was synthesized by a simple one-pot procedure involving partial hydrolysis of H₂SiCl₂ and the following ammonolysis reaction of the hydrolyzed intermediates with NH₃. The structure of new polymer was characterized with perhydropolysiloxane (PHSO) and perhydropolysilazane (PHSN) as reference substances. The conversion of PSNO to ceramic was investigated by TGA, FT-IR, and solid ²⁹Si-NMR analyses. A Si-rich Si₂N₂O ceramic was produced upon pyrolysis of PSNO at 1400°C under N₂ atmosphere. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

A new polyaminoborazine with good solubility was synthesized by ammonolysis reaction of a mixture of B-chloroborazine, B-bischloroborazine, and B-trichloroborazine under mild condition. The oligomer was easily cured at 250°C. The pyrolytic residue of the cured oligomer was investigated with X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and thermal gravimetric analysis (TGA). The results indicated that crystalline h-BN with B/N ratio of 1:1.01 is main in the residue pyrolyzed at 1500°C. Copyright © 2010 John Wiley & Sons, Ltd.

Polyborosilazanes (PBSZs) were synthesized by co-ammonolysis of 2,4,6-trichloroborazine and dichloromethylsilane and used as precursors for SiBCN ceramics. The pyrolyzed products were characterized with Fourier transform infrared, X-ray photoeletron spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction, and scanning electron microscopy (SEM). The results indicated the content of B or Si plays an important role in controlling the high temperature behavior of the precursors. The resistance of the ceramics, which were obtained from pyrolysis of PBSZs at 1500°C, toward oxidative attack up to 1000°C was also investigated by TGA and SEM/EDX. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

New polyferrocenylsiloxanes (PFSXs) and polyferrocenylsilazanes (PFSZs) with linear or linear-cyclic structure were prepared. The ceramic yields of the polymers were estimated by thermogravimetric analysis (TGA) and bulk pyrolysis, which closely depend on molecular structures. Compared with that of their linear counterparts having comparable molecular weights, the ceramic yields of linear-cyclic PFSX and PFSZ were much higher. The pyrolysis process was investigated by lysis character is (TGA) highly depend on their molecular weights and structures, infrared spectra, and pyrolysis-gas chromatography-mass spectra (Py-GC-MS) analysis. The results indicated rather amount of ferrocene-based small molecules were formed during the pyrolysis of linear polymers in the range of 25–300°C, whereas the existence of crosslinking or branched structure in the linear-cyclic polymers prohibited this transformation, and therefore, dramatically improved the ceramic yields. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010