A novel flame retardant (SDPS) containing PAOASi bands was synthesized by a condensation polymerization of diphenylhydroxysilane and spirocyclic pentaerythritol di(phosphate monochloride). The structure of SDPS was confirmed by Fourier transform infrared spectroscopy (FTIR) and 1 H nuclear magnetic resonance ( 1 H NMR). Limiting oxygen index (LOI) test showed that when loading 22.5 wt % SDPS and 7.5 wt % in polypropylene, LOI value markedly increased to 31.4% in comparison with PP/ SDPS (30 wt %) and PP/MP (30 wt %) systems. Combusting experiment further proved a synergistic effect of SDPS and melamine polyphosphates (MP) in flame retarding of polypropylene. Thermogravimetric analysis (TGA) and FTIR-TG results revealed that the synergistic effect was attributed to a catalyzed breaking down of PAOASi bands in the presence of MP, which acted as an acid catalyst, consequently leading to a facilitated char and silica forming process.

Uniform and monodisperse boehmite (γ-AlOOH) nanosheets with a thickness of less than 20 nm have been prepared by the hydrothermal treatment of amorphous boehmite. XRD and FTIR analysis showed that boehmite nanosheets have uniform and high degree of crystallinity. SEM micrographs indicated that boehmite has a leaf-like morphology with high anisotropy (with a length of 0.25～1 m and a width of 50～100 nm).

Copolymer of p-phenylenediamine and bispirocyclic pentaerythritol diphosphate was synthesized and characterized by FTIR and 1H NMR. This polymer was used to prepare epoxy resin/SPDA composites. Thermal stability of SPDA and epoxy/SPDA composites were investigated by thermogravimetric analysis (TGA), and their flammability were investigated by the LOI test. TGA results showed that the addition of SPDA improved the char residue of epoxy resin. SEM investigation showed that the residual chars have a honeycomb-like structure, indicating an intumescent flame retarding effect of SPDA in composites. In addition, all of above results confirmed that accelerate carbonization play a key role in improving flame retardancy of epoxy resin.

A new silicon-phosphorus hybrid (SPH) flame retardant was synthesized by condensation reaction of 1-oxo-4-hydroxymenthyl-2,6,7-trioxa-1-phosphabicy[2,2,2] octane (PEPA) with waste silicon oil which is mainly consisted of the compounds of CxHySizCln. The effect of Si/P hybrid on the flame retardancy of polypropylene composites (PP/Si-P) was studied by limiting oxygen index (LOI) test and thermogravimetric analysis (TGA). The flame retarding performance of PP/SPH/MP/PER at the same loading amount is slightly higher relative to MP/PER. This, in plus to the low cost and the value in environmental protecting, makes SPH possess the application potential in flame retardants.

Alkyl substituted disiloxanes demonstrated promising applications as high performance hydraulic oil, diffusion pump oil, etc. In this study, fluorinated alkyl substituted disiloxane was synthesized via Grignard reaction followed by condensation reaction. Its chemical structure was verified by FTIR and NMR. Measurement results showed that this silicon oil exhibited good high temperature performance, oxidation resistance and rust resistance.