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The effects of two binders (PET and HTPB) on thermal decomposition characteristics of Ammonium Perchlorate were studied by TG-FTIR, DSC and SEM. When Hydroxyl-terminated polybutadiene (HTPB) mixes with AP, there is no obvious mutual effect in the process of heating, but it happen in the other way when Hydroxyl-terminated random copolyether (PET) mixes with AP. During the heating process of PET-AP mixture, the decomposition of PET occur in advance significantly, so that the porous structure of AP at the low-temperature decomposition stage becomes more significant, the total amount of heat released increases significantly, and the weight-loss ratio of AP about the two stages increases to about 2:1. During the thermal decomposition, the heat release and N 2 O gas production of PET-AP mixture is milder than the HTPB-AP, which is more conducive to the insensitive properties of propellant.

The high-performance solid propellants play very important role in defense industry, which required highly energetic binders with good mechanical properties. In order to get the activation parameters for energetic binders, In-Situ FT-IR spectroscopic technique is used to study the chemical kinetics of glycidyl azide polymer (GAP) and hydroxyl terminated poly butadiene (HTPB) with isophorone diisocyanate (IPDI) at various temperatures. The reaction was followed by monitoring the change in intensity of the absorption band of NCO stretching at 2257cm-1and CO stretching at 1731cm-1. The polyurethane reaction has been found to be second order and the rate constant seems to be different between GAP/IPDI and HTPB/IPDI due to reactivity difference of OH groups. Dibutyl tin dilurate (DBTDL) was used as curing catalyst. By using Arrhenius and Eyring equations, the activation parameters were obtained at different temperatures (60, 70, 80 and 90°C). The apparent activation energy for the two systems GAP/IPDI and HTPB/IPDI were found to be 63.51 kJ mol-1and 41.06 kJ mol-1while the enthalpy and entropy of activation were found to be 62.35 kJ mol-1and-36.24 kJ.mol-1K-1, 39.08 J mol-1and-98.84 J mol-1K-1respectively.Key words: In-Situ FT-IR; glycidyl azide polymer (GAP); hydroxyl terminated poly butadiene (HTPB); chemical kinetics; polyurethane; dibutyl tin dilurate (DBTDL).

Solid composite propellants are extensively used for propulsion of rockets, missiles and space applications. The composite propellant is a polymeric matrix in which the oxidizer and fuel particles are embedded in a polymeric binder. Different composite propellant mixtures have been prepared using ammonium-perchlorate (ratio 70:30) as oxidant and mixture of aluminium powder (ratio 50:50) as metal component. In the present work, RDX (Cyclotrimethylene trinitramine) has been used in successive increments replacing AP (Ammonium Perchlorate) in number of batches by varying the percentage of solid loading, and studied their different properties such as viscosity build-up, mechanical and ballistic properties.

Determination of TiOCl2 in refined TiCl4 was significant for analysis of its impurities. TiOCl2 could be determined by infrared spectroscopy due to its infrared characteristic spectrum line. However, normal infrared absorption cell was not fit for the sample analysis, because TiCl4 easily reacted with moisture in the air and immediately was hydrolyzed to form highly corrosive hydrochloric acid smoke. The infrared absorption cell with the window film of ZnSe ( Ф10×1mm, wavenumbers: 7800cm-1~440cm-1) and the glass cell (optical path: 22mm, 12mm, 7mm and 4mm) was assembled and utilized in determination of the TiOCl2 in refined TiCl4 by standard addition method. The detection limit of TiOCl2 was 26.5mg•kg-1, the regression equation was Y=1.0118X, R2=0.9926; With standard addition method, the regression equation of TiOCl2 was Y=1.9400X, R2=0.9940,This infrared absorption device was safe, simple and convenient, easily removable and washable, and re-useable. This method could meet the requirement of determination of TiOCl2 in refined TiCl4.

AP-based nanolimit growth energetic materials (NLGEM) were prepared by using SiO2 gel as nanolimit growth skeleton materials and using sol-gel method combining solution crystallization to make AP recrystallized in the nanopores of SiO2 gel skeleton to form AP/SiO2 NLGEM. The chemical and physical structure and properties of AP/SiO2 NLGEM were studied in detail. AP with nanoscale particles size range from 69nm to108nm was recrystallized in the pore of SiO2 gel skeleton and the particle size of AP increased with the amount of AP in NLGEM increasing. Moreover, the preparation method didnt change the crystal form of AP and bring impurities to NLGEM. The decomposition of AP/SiO2 NLGEM was a one-step process, which was indicated its decomposition was more concentrate than pure AP and AP/SiO2 simple physical mixture (AP/SiO2 SPM), whose decomposition was a two-step process. At the time, the decomposition heat of AP/SiO2 NLGEM was higher than that of pure AP and AP/SiO2 SPM. The sensitivity of AP/SiO2 NLGEM was lower than those of the pure energetic components and physical mixtures according to the impact sensitivity test.

Hyperbranched polymer/HTPB-PU IPNs were prepared, when HTPB (hydroxyl-terminated polybutadiene) and IPDI (isophorone diisocyanate) were cured into polyurethane (HTPB-PU) at the existence of hyperbranched polymer. Differential scanning calorimetry (DSC) was adopted to study the influence of hyperbranched polymer on thermal properties of HTPB-PU, while IPNs were formed. The result shows that the existance of hyperbranched polymer makes glass transition temperature of HTPB-PU reduces by around 2°C and that HTPB-PU lowers the melting point of hyperbranched polymer. Hyperbranched polymer plays a role of internal plasticization on HTPB-PU, and HTPB-PU influences crystallization of hyperbranched polymer in return.

Uniform and well-dispersed photoluminescent semiconductor CdSe (Cadmium selenium) QDs (Quantum dots) were in-situ prepared by taking G4.0-NH2PAMAM(polyamidoamine) dendrimers as inner templates in water and methanol respectively. The prepared solutions containing photoluminescent semiconductor CdSe QDs were utilized for detection of unfumed oil fingerprints on tinfoil. The results show that unfumed latent fingerprints treated with prepared CdSe/PAMAM nanocomposites both displayed yellow emission and the latent fingerprints were detected clearly, while treated with CdSe/PAMAM composites in water manifested stronger emission compared with those treated with CdSe/PAMAM composites in methanol; Also, the veins of fingerprints treated with CdSe/PAMAM nanocomposites in methanol became slim because of the dissolution of methanol to oil components in fingerprints.

The content control of the impurities in refined TiCl₄ becomes the key part for the quality control of titanium material. Refined TiCl₄ is the key procedure in producing titanium sponge. Besides, the content of the impurities in titanium sponge and that of the impurities in refined TiCl₄ presents the 4-times enrichment relationship. Therefore, control the content of the oxygen, there is the need to analyze the source of oxygen impurities so that strict control can be conducted over the impurities of refined TiCl₄. Determination of TiOCl₂ in refined TiCl₄ was significant for analysis of its impurities. TiOCl₂ could be determined by infrared spectroscopy due to its infrared characteristic spectrum line. However, normal infrared absorption cell was not fit for the sample analysis, because TiCl₄ easily reacted with moisture in the air and immediately was hydrolyzed to form highly corrosive hydrochloric acid smoke. According to Lambert-Beer Law, which means the concentration (c(x)) and absorbance (A)-length (L) curve's slope have direct ratio. The infrared absorption cell with the window film of ZnSe (Φ10 x 1 mm, wavenumers: 7800-440 cm⁻¹) and the glass cell (optical path: 22, 12, 7 and 4 mm) was assembled and utilized in determination of the TiOCl₂ in refined TiCl₄ by standard addition method. The detection limit of TiOCl₂ was 17.8 mg · kg⁻¹, the regression equation was Y = 1.011 8X, R = 0.9963; With standard addition method, the regression equation of TiOCl₂ was Y = 1.940 0X, R = 0.997 0, it' s good in linearity relation, the TiOCl₂ content in refined TiCl₄ is determined to be 833.8 mg · kg⁻¹ and SD up to 40.0 mg · kg⁻¹. RSD of the method precision is between 0.95%-1.94%, while recovery rate is between 88.5%-93.1%. This infrared absorption device was safe, simple and convenient, easily removable and washable, and re-useable. The method could conduct the quantitative analysis over the TiOCl₂ content in refined TiCl₄ through adding standard sample for one time, it could meet the requirement of determination of TiOCl₂ in refined TiCl₄.

In order to improve mechanical properties of polyurethane, hyperbranched interpenetrating network(H-IPN) was achieved by incorporating hyperbranched polyethrs into polyether-Urethane that derived from hydroxyl terminated ethylene oxide tetrahydrofuran copolyether (PET) and isophorone diisocyanate (IPDI). It was found that H-IPN exhibited dual-phase morphology, and hydrogen bonding was formed between hyperbranch polyether and polyether-Urethane. H-IPN shows synergetic effect, the tensile strength of H-IPN increased from 1.39MPa of neat polyether-Urethane to 2.67 MPa; Meanwhile, the elongation increased from 605% of control sample to 2304%.

In order to investigate influence of end-groups on thermodynamic property and viscosity of hyperbranched polyether. Three series of hyperbranched polyethers with three different end-groups were studied. These three groups are: hydroxyl, acetate and stearic acid ester. The result confirms the complicated effect of end-groups on properties of hyperbranched polymer. When end-groups change from polar groups of hydroxyl to non-polar groups of acetate, glass transition temperature reduced about 50°C, viscosity reduced sharply too. Glass transition temperature and viscosity all increase with generation rise. When end-groups change from acetate to stearic acid ester, corresponding hyperbranched polyether change from amorphous to crystalline. The crystallization stemmed from long chain structure of end-group, which is easy to form crystalline, its crystalline region molten become main thermodynamic transformation, and obscure the glass transition.

CdS(Cadmium sulfide)/PAMAM(polyamidoamine) Nanocomposites were in-situ prepared taking PAMAM dendrimers as stabilization in water. The prepared solution containing photoluminescent semiconductor CdS QDs(Quantum dots) was utilized for detection of aged fingermarks on adhesive tape strips. The fingermarks were aged for 1 d, 7 d and 30 d in nature light respectively. The results show that the latent aged fingermarks treated with CdS/PAMAM nanocomposites emit yellow luminescence under ultraviolet excitation of 365 nm in the dark. Aged fingermarks were detected successfully with better resolving rate comparing with existing nano-scale commercial TiO2powder suspension.

Uniform and well-dispersed photoluminescent semiconductor CdSe(Cadmium selenium) QDs(Quantum dots) werein-situprepared stabilized by G4.0-NH2PAMAM dendrimers in water and effects of metallic ions such as Zn2+, Cd2+, Cu2+, Ag+, Pb2+, K+, Na+on the photoluminescence(PL) properties of CdSe QDs were studied using spectrophotometric titration. The results show that Zn2+and Cd2+ions enhance the PL intensity of CdSe QDs, Cu2+, Ag+and Pb2+ions quench the PL intensity, while K+and Na+ions have no obvious effects. Those are attributed to the surface modification of CdSe QDs. Excess Cd2+ions can reduce the non-combination centers, increase the passivation of PAMAM on the surface of CdSe QDs, and form a Schottky-like barrier which enhanced the PL efficiency. Excess Zn2+ions can also increase the PL intensity of CdSe QDs in the same way as Cd2+ions because of the much similar lattice parameters of CdSe and ZnSe. However, a CuSe, Ag2Se or PbSe shell on CdSe QDs emerges due to the substitution of Cd2+ions, which leads to the decrease of band-edge emmiting of CdSe QDs. And the quenching effect of Ag+is stonger than Cu2+and Pb2+because of the lower solubility of Ag2Se formed on the surface of CdSe QDs. Oil latent fingerprints deposited on tinfoil surface treated with CdSe/dendrimer NCs(Nanocomposites)、Cd2+-CdSe/ PAMAM NCs and Zn2+-CdSe /PAMAM NCs emitted bright yellow photoluminescence under ultraviolet excitation of 365nm from an UV LED in the dark., among, fingerprint treated with Cd2+-CdSe/dendrimer NCs and Zn2+-CdSe /PAMAM NCs was detected with better resolving rate.

The expanding properties of limestone from 200°C to 700°C were investigated under high temperature and bidirectional restraints with the device used to heating rock designed by ourselves. The experimental results show that the two directional expanding stress of limestone increased with temperature increasing during raising temperature before 600°C, and decreased after 600°C. The expanding stress perpendicular to bedding plane was bigger than that parallel to bedding plane. The curves of expanding stress and temperature ascend steadily during constant temperature before 600°C, but the slopes were much less than those during raising temperature. The expanding stress tended to steady value at last with the time of constant temperature prolonging. The expanding stress when constant temperature ended was smaller than those before constant temperature at 700°C. It showed that the limestone had expanded to the limit value after a certain temperature. The expanding stress reduced possibly after a certain temperature because the rock sample was restricted and some fissures closed and the number of cracks reduced after over-high temperature, but the detailed cause needs more researches to testify it.

Structures of ferrocene containing hyperbranched polyester (HBPE-Fc) was characterized by FTIR and H1 NMR. The spectroscopic analysis provided evidence of the successful modification of ferrocene toHBPE. The catalytic performances for thermal decomposition of ammonium perchlorate (AP) were investigated by DSC techniques. The kinetic parameters were computed by the Kissinger method. The results indicated that the presence of HBPE-Fc reduces the maximum decomposition reaction temperature in AP samples. HBPE-Fc presented an efficient catalytic effect on the thermal degradation of AP and the catalytic reactions were characterized by decreased activation energy and increased rate constant of thermal decomposition. The possible catalytic mechanism was proposed.

A novel fluorinated polyurethane (FPU) with fluorine-containing pendent groups was prepared by using fluorinated polyether glycol (PTMG-g-HFP) as a soft segment, 1,6-hexamethylene diisocyanate (HDI) or toluene diisocyanate (TDI) as a hard segment and 1,4-butanodiol (BDO) as a chain extender. FTIR, 1H NMR, 13C NMR and GPC were used to characterize the structure of the fluorinated polyurethane. Thermal stabilities of the fluorinated polyurethane and the corresponding hydrogenated polyurethane were studied by TGA. XPS analysis at two different sampling depths for the fluorinated polyurethane was used to investigate the surface compositions of FPU. The results showed the fluorine enrichment on the surface of FPU.

Refined TiCl4 is the key procedure in producing titanium sponge. Besides, the content of carbon and oxygen (C and O) impurities in titanium sponge and that of C and O impurities in refined TiCl4 presents the 4-times enrichment relationship. Therefore, the content control of the C and O impurities in refined TiCl4 becomes the key part for the quality control of titanium material. In order to control the oxygen and carbon, there is the need to analyze the source of C and O impurities so that strict control can be conducted over the impurities of refined TiCl4. Determination of CO2 in refined TiCl4 was significant for analysis of its impurities. CO2 could be determined by infrared spectroscopy due to its infrared characteristic spectrum line. However, normal infrared absorption cell was not fit for the sample analysis, because TiCl4 easily reacted with moisture in the air and immediately was hydrolyzed to form highly corrosive hydrochloric acid smoke. According to Lambert-Beer Law, which means the concentration (c(ξ)) and absorbance(A) - length (L) curve's slope have direct ratio. The infrared absorption cell with the window film of ZnSe (φ10 mm x 1 mm, wavenumers: 7 800 -440 cm(-1)) and the glass cell (optical path: 42, 22, 12, 7 and 4 mm) was assembled and utilized in determination of the CO2 in refined TiCl4 by standard addition method. The detection limit of CO2 was 0.92 mg x kg(-1), the regression equation was Y = 0.031 1X, R = 0.997 2; With standard addition method, the regression equation of CO2 was Y = 0.131 7X, R = 0.998 6, it's good in linearity relation, the CO2 content in refined TiCl4 is determined to be 1.53 mg x kg(-1) and SD up to 0.04 x mg x kg(-1). RSD of the method precision is between 0.53%-1.27%, while recovery rate is between 89.2%-96.8%. This infrared absorption device was safe, simple and convenient, easily removable and washable, and re-useable. The method could conduct the quantitative analysis over the CO2 content in refined TiCl4 through adding standard sample for one time, it could meet the requirement of determination of CO2 in refined TiCl4.

A new method for the synthesis of 4,4′,6,6′-tetra(azido)azo-1,3,5-triazine (TAAT) is described. The key intermediate 4,4′,6,6′-tetra(azido)hydrazo-1,3,5-triazine (TAHT) was synthesized by nucleophilic substitution in the case of sodium azide as nucleophile. N-Bromosuccinide (NBS) was used as oxidant to oxidize TAHT by a tractable operation under mild reaction condition. The target compound TAAT was obtained with a facile process and high overall yield of 81%. The structures of TAAT and its intermediates were identified by spectroscopic methods.

The photoluminescence property of CdS/PAMAM nanocomposites in water at different ratio of Cd2+ to PAMAM(r) was studied by fluorescence emission spectrum, and the according mechanism was explored. The results indicate that in the irradiation of UV light at the wavelength of 330 nm, two peaks were shown in the fluorescence emission spectrum of CdS/PAMAM nanocomposites. One peak was attributed to PAMAM dendrimers, and the another came from CdS QDs. The strength of the frontier fluorescence emission peak became weaker and weaker, and at last disappeared with the enhancement of the ratio of Cd2+ to PAMAM; the strength of the latter fluorescence emission peak became stronger, which indicates that the electron at valence band of N atom in amines of dendrimers was transferred to CdS QDs. Oil latent finger marks deposited on transparent adhesive tapes surface treated with pure PAMAM solution with blue photoluminescence was not clear enough because of the blue light emitted from the impurity in adhesive tapes; Latent finger marks emitted strong yellow light and were successfully detected with good resolving rate with CdS/dendrimer solution with r of 10, which shows good reference value for detecting finger marks on surfaces with impurities emitting different photoluminescence colors.