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A novel phosphorus, nitrogen-containing compound, poly(4, 4′-diaminodiphenyl methane phenyl dichlorophosphate) (PDMPD) with high thermal stability was synthesized. The PDMPD was then incorporated into polystyrene (PS) to be used as halogen-free flame retardant. Moreover, small amounts of two boron-containing compounds, Zinc borate (ZnB) and boron phosphate (BP) were combined with PDMPD,to explore effective flame-retardant formulations for PS. The flammability and the thermal properties of the composites were evaluated using limiting oxygen index (LOI) test, microscale combustion calorimeter (MCC) and thermogravimetric analysis (TGA) respectively. A Fourier transform infrared (FTIR) spectroscopy coupled with a thermogravimetric analyzer (TG-IR) was also used to study the gas phase from the degradation of PS composites. Furthermore, the char residues of the samples were investigated by scanning electron microscopy (SEM) and FTIR. The results showed that the incorporation of PDMPD can significantly decrease the flammability of virgin PS, and enhance the thermal stability at high temperature region, in both nitrogen and air atmosphere. A combination of PDMPD with small amounts of boron compounds can further decrease the flammability. [ABSTRACT FROM AUTHOR]

A series of flame retardant hybrids were prepared based on bisphenol A polycarbonate (PC), trisilanolphenyl-polyhedral oligomeric silsesquioxane (TPOSS) and oligomeric bisphenyl A bis(diphenyl phosphate) (BDP) by melt blending method. The thermal stability and flame retardant properties of the hybrids were investigated by thermogravimetry analysis and cone calorimeter. Combination TPOSS with BDP in the appropriate ratio enhanced the thermal stability and the flame retardant properties of the PC matrix. The char residues of the hybrids were investigated by scan electronic microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The synergistic effect of BDP and TPOSS enhances the thermal stability and fire-resistance of the char layer which builds up on the surface of the burning polymer. [ABSTRACT FROM AUTHOR]

Ferric pyrophosphate (FePP) was used as additive to study its synergistic effect of thermal degradation on cotton fabrics. The microscale combustion calorimetry (MCC), thermogravimetric analysis (TG), Raman spectroscopy and Real Time Fourier transform infrared spectroscopy (RT-FTIR) were utilized to evaluate the synergistic effects of FePP on cotton/DIA. The MCC results revealed that cotton/DIA/FePP generated less combustion heat during heating than that of cotton/DIA. TG results showed that presence of FePP improved the thermal stability of materials. The Raman spectroscopy test showed that FePP can ameliorate the structural organization level of the carbon and the graphitization degree of the char. RT-FTIR data revealed the mechanism of the influence of FePP, which can catalyze the break of the flame retardant as well as promote the char forming. [ABSTRACT FROM AUTHOR]

UV-curable waterborne polyurethane acrylate (WPUA) modified with octavinyl polyhedral oligomeric silsesquioxane (OVPOSS) was prepared via photopolymerization between OVPOSS and WPUA. Structural and morphological features of WPUA/OVPOSS coatings were assessed using Fourier transform infrared spectroscopy, transmission electron microscopy and X-ray diffraction. Thermal properties of the WPUA/OVPOSS hybride coatings have been improved over the pure waterborne polyurethane acrylate analyzed by thermal gravimetric analysis. Performance of the coatings was also evaluated using water absorption, hardness, contact angle, X-ray photoelectron spectroscopy (XPS). The data showed that the WPUA/OVPOSS coatings possessed better water resistance and thermal oxidative stability in comparison with pure WPUA. [ABSTRACT FROM AUTHOR]

Phosphorus-modified siloxanes monomer DOPO-IPDI-AMEO (DIA) was synthesized and characterized by H nuclear magnetic resonance (H NMR), P NMR, and Fourier transform infrared spectra (FTIR). It hydrolyzed and grew an organic-inorganic hybrid coating on the surface of cotton fabrics via sol-gel process. The conversion of gel reaction was characterized by solid-state Si NMR. The effect of the modified organic-inorganic hybrid materials on thermal properties of cotton fabrics was investigated by thermogravimetric (TG) analysis, real time Fourier transform infrared (RT-FTIR), and microscale combustion calorimetry (MCC) experiments. In addition, thermogravimetry-Fourier transform infrared spectra (TG-FTIR) were used to investigate the released degradation products. The characterization information represented that DIA has been prepared successfully. Also the conversion of gel reaction was fairly high. The TG data showed that char residues increased with the addition of the DIA coating. While the peak heat release rate (PHRR) decreased with the presence of the coating in MCC test. Moreover, the flammable degradation products dropped obviously, which can be observed from the data of TG-FTIR. [ABSTRACT FROM AUTHOR]

We investigated the thermal decomposition behaviors of two typical grains, rice and corn, using a thermogravimetric analyzer at different heating rates. The pyrolysis process of rice and corn both can be divided into three stages, and the most possible pyrolysis mechanism of both rice and corn during devolatilization is a three-dimensional diffusion reaction, which can be represented by the Zhuravlev equation (G(α) = [(1 − α)(−1/3) − 1]2). Corn had a higher initial degradation temperature and end temperature as well as a higher mass loss in the second stage than rice. The average Ea of rice determined by Kissinger, FWO and Friedman method was 143.6 kJ mol−1, 161.6 kJ mol−1 and 148.7 kJ mol−1, respectively. The average Ea of corn determined by Kissinger, FWO and Friedman method was 166.1 kJ mol−1, 146.3 kJ mol−1 and 170.4 kJ mol−1, respectively. A lower Ea of rice than corn also indicates that rice is easier to be pyrolyzed. The predicted values using the kinetic parameters calculated show a good agreement with the experimental data at all the four heating rates. The results presented herein could provide guidance for storage of grains. [ABSTRACT FROM AUTHOR]

Two kinds of novel phosphorus-containing polyether toughening agents were synthesized and characterized by H nuclear magnetic resonance (H NMR) and Fourier transform infrared spectra (FTIR). Afterwards, a series of phenolic foams with different loadings of phosphorus-containing toughening agents were prepared. The apparent density and scanning electron microscopy (SEM) results showed that the addition of 5 wt% toughening agents increased the expansion ratio and promoted the formation of uniform cells. The limiting oxygen index (LOI) values of modified phenolic foams decreased with the increase of modifier content, but it still remained at 40% even if the amount of modifier loadings was 10 wt%. UL-94 results showed all samples can pass V0 rating, indicating the modified foams still have great flame retardance. Microscale combustion calorimetry (MCC) results indicated that the peak heat release rate (PHRR) and total heat release (THR) of the modified foams were reduced by 42% and 35%, respectively, compared to the pure phenolic foams. Moreover, the thermal stability of samples was investigated by thermogravimetric analysis (TGA). The mechanical properties were evaluated and correlated with composition and structural features. [ABSTRACT FROM AUTHOR]