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It is a potential way to enhance the performance of the DSSCs by constructing a GO-TiO2 composited photoanode with graphene oxide.

Piperazine spirocyclic phosphoramidate (PSP), a novel halogen-free intumescent flame retardant, was synthesized and used to improve the flame retardancy and dripping resistance of polypropylene (PP) combined with ammonium polyphosphate (APP) and a triazine polymer charring-foaming agent (CFA). The optimum flame-retardant formulation was PSP:APP:CFA 5 3:6:2 (weight ratio). The flammability and thermal behavior of the (intumescent flame-retardant)-PP (IFR-PP) were investigated via limiting oxygen index (LOI), vertical burning tests (UL-94), thermogravimetric analysis, and cone calorimetry (CONE). The results indicated that the IFR-PP had both excellent flame retardancy and anti-dripping ability. The optimum flame-retardant formulation gave an LOI value of 39.8 and a UL-94 V-0 rating to PP. Moreover, both the heat release rate and the total heat release of the IFR-PP with the optimum formulation decreased significantly relative to those of pure PP, according to the cone calorimeter analyses. The residues of IFR-PP obtained after CONE tests were observed by scanning electron microscopy, and it was found that the char yield was directly related to the flame retardancy and anti-dripping behavior of the treated PP. J. VINYL ADDIT. TECHNOL., 20:10-15, 2014.

Nano-silica had been used as a synergistic agent for the preparation of aluminum diethylphosphinate (AlPi) flame retardant polyamide 66 (PA66/AlPi) and PA66/AlPi/nano-silica composites through twin-screw extrusion. The limiting oxygen index (LOI), used to characterize the minimum amount of oxygen needed to sustain a candle-like flame, revealed that the PA66/10%AlPi/1%nano-silica composites exhibited an excellent flame retardant efficiency with a high LOI value of 32.3%. The vertical flame test (UL-94) revealed that the PA66/10%AlPi/1%nano-silica composites passed the V-0 rating without drop melting. Cone calorimeter test revealed that the heat release rate and total heat rate for the PA66/10%AlPi/1%nano-silica composites were significantly decreased by 51.1 and 16.8%, respectively, compared with those of pure PA66. The thermogravimetric analysis showed that the PA66/10%AlPi/1%nano-silica composites had vast chars of 8.1% even at 800°C, indicating that nano-silica could promote the char formation of the PA66 composites. Scanning electron microscopy indicated a solid and tough residue of the burned PA66/10%AlPi/1%nano-silica composites as compared with the very loose and brickle residue of the burned pure PA66, indicating that a suitable amount of nano-silica played a synergistic effect in the flame retardancy.