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In this study, N,N-(2,4-diamino-1,3,5-triazinyl) diethylenetriamine were synthesized by cyanuric chloride, diethylenetriamine and ammonia with a novel process in three steps, and it can be used as charring agent in intumescent flame retardant. Its chemical structures were characterized by Fourier-transform infrared spectroscopy (FT-IR) and elemental analysis. Meanwhile, the TGA results showed that triazine-based charring agent had good thermostability. Furthermore, the fire performancce of composites blended by the flame retardant and polypropylene was investigated by vertical burning test. The results revealed good fire retardancy that flame retardant polypropylene with 5.1wt% charring agent, 2.8wt% anti-dripping and 20.1wt% APP, was reached UL-94 V-0 rating.

In this study, a novel polyhydroxy triazine charring agent (PT-CA) was synthesized through the solid-state reaction of triglycidyl isocyanurate (TGIC) and pentaerythritol. Meanwhile, the molecular structure of the chemical compound was determined by FTIR, elemental analysis and thermalgravimetric analysis (TG).Then it is combined with microencapsulated ammonium polyphosphate (MAPP) and melamine phosphate (MP) to impart flame retardance and dripping resistance for polypropylene (PP).The fire performance of treated PP was investigated by limiting oxygen index (LOI) and vertical burning test (UL-94).It has been found that the treated PP with the optimal flame retardant formulation of MAPP:MA:PTCA=18:6:6 (weight ratio, formulation 10) gives an LOI of 31.5 and UL-94 V-0 rating.

In this study, a novel flame retardant 1,2-bis (dimelaminium of 1-nitro-3,5-diphospha-4-oxa-3,5-dihydroxy cyclohexane) ethane (EAPM) was synthesized by ethylene diamine tetra (methylene phosphonic) acid (EDTMPA) and melamine in two steps. Meanwhile, its molecular structure was determined by Fourier-transform infrared spectroscopy (FT-IR), elemental analysis, 1H-NMR. The thermal properties were characterized by TG and DTG, which indicated the good thermostability of EAPM for processing and the considerable residual char in the final stage of combustion. The fire performance of composites blended by the novel flame retardant and polypropylene waere investigated by limiting oxygen index (LOI) and vertical burning test. The results demonstrated the treated PP with the optimal flame retardant formulation of 15 w% EAPM, 5 w% charring agent and 10 w% MEL-APP was attached with an LOI of 33.3% and UL-94 V-0 rating.

In this paper, a series of novel halogen compounds, melamine halogen acid salts were directly synthesized by melamine and halogen acid in water phase. The chemical structures of melamine halogen acid salts were characterized by Fourier-transform infrared spectroscopy (FT-IR), elemental analysis and1H-NMR. Meanwhile, the thermal properties of compounds were investigated by thermogravimetric analysis (TGA). The TGA results showed that melamine halogen acid salts had good thermostability during polymer processing. Futhermore, limiting oxygen index (LOI) and vertical burning test were used to study the flame retardant properties of composites blended by melamine halogen acid salts and polymer. The results revealed good flame retardancy that flame retardant polyethylene with 2 wt% melamine hydrobromide in total 8 wt% flame retardants got LOI value of 29.7% and reached UL 94 V-0 rating.

The process parameters and operation effect of the treatment of comprehensive wastewater of chemical industry park by anaerobic/aerobic bio-contact oxidation process was introduced. This provided a reference of application. Taking a project as an example, process flows, parameters and the size of structures were introduced. Combining with treatment effect, the design features were discussed. The practical operation result showed that the effluent treated by the baffled submerged bio-film process could meet the requirement of classⅡ of the “Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant” (GB18918-2002).

In this paper, a novel flame retarded MCA-PA6 (PA6 incorporated with melamine cyanurate) resin was synthesized by in-situ polymerization. The synthetic product was characterized by X-ray diffraction (XRD), scanning electronic microscopy (SEM), Fourier transform infrared spectroscope (FTIR), thermogravimetry analysis (TG), differential scanning calorimetry (DSC) and elemental analysis. The result showed that good dispersability were obtained in MCA-based PA6 prepared successfully. Meanwhile, the maximum mass loss rate appeared at about 450 °C and the residual char increased from 1.2 wt% to 3.2 wt% at 500 °C due to the existence of MCA.This research revealed MCA-PA6 owned a good thermal stability, hence there was potential flame retardance.

In this study, a novel phosphorus-nitrogen containing intumescent flame retardant (P-N IFR) poly(melamine 2-carboxyethyl(phenyl) phosphate)(PMCEP) was prepared via the reaction of 2-carboxyethyl (phenyl) phosphinic acid (CEPPA) and melamine (MEL) in two-steps. Meanwhile, the molecular structure of the chemical compound was determined by FTIR,1H-NMR and elemental analysis; and the thermal properties was investigated by means of TGA. Combustion studies revealed high limiting oxygen index (LOI) indicative of better flame-retardancy properties for PBT resin.

In this study,a new thermoplastic elastomer based on polyamid 6, and polytetrahydrofuran was prepared by continuous hydrolytic ring-opening polymerization process. The effective of adipic acid content on the number-average molecular and the content of amino end groups was investigated. The morphology deduce of TPMP, mechanical performances were also investigated.

The finite element contrast model such as concrete filled steel tube support, U-steel support and hollow steel tube support were established with ANSYS software, combining with engineering practice and relative design scheme of concrete filled steel tube test, respectively analysis their influencing factors and mechanical properties such as support effect, bearing capacity and so on. The economic benefit of each support was been analysised by comprehensive comparison of the material using condition and mechanical performance. The results show that, comparing with traditional U-steel support, retractable concrete filled steel tube support is a new style support with high bearing capacity, a large variety of sizes, higher economic benefit, and hence fit to support the deep soft rock broken jointed rock mass.

As the implementations of the western development in China, more and more tunnels will get through the western mountains in China. In order to economize the construction costs, a new type of underground structural form called branching-out tunnel must be applied. The failure process of the branching-out tunnel under lateral overload action is also greatly complicated, which is related with the depth of the mountains, the branching-out angle, the in-situ stress field, the thickness of the middle wall and so on. This paper uses the 3D-physical model of geo-mechanical model tests to study the stability and failure process of this complicated structure, especially the part of the middle wall. The physical model is built up in a new kind of analogy material. In the process of the whole experiments, different lateral pressures imposed on both of the lateral planes of the physical model. According to different lateral pressures, we have attained the change of the stress and displacement field and looked into the failure process of the pivotal positions in the branching-out tunnel. We also use finite element method analysis software RFPA (Realistic Failure Process Analysis) to simulate the whole failure process of the branching-out tunnel. Finally, we have got the load-bearing safety reliability of this complicated structure through comparative analysis of physical modeling and numerical simulation.