聚氨酯涂层剂分析和测试方法

本文介绍了溶剂型和乳液型聚氨酯（PU）涂层剂的红外分析法，对红外谱带与基团振动列表对照，有利于区分异氰酸酯类别。文章重点介绍了PU涂层剂的一般和专项性能测试，对提高和稳定涂层和涂层产品质量有一定帮助。

Increase in functional groups for POSS by introducing branched phenylglycidylether

In the selected experimental conditions, firstly, the branched products with functional groups, N-（2-hydroxylpropylphenylether） （3-aminopropyl） triethoxysilane （APES-PGE, containing one hydroxyl group） and N-[di（2-hydroxylpropylphenylether）]（3-aminopropyl） triethoxysilane （APES-PGE2, containing two hydroxyl groups）, were synthesized by reacting 1 mole of （3-aminopropyl）triethoxysilane （APES） with 2 mole of phenylglycidylether （PGE）. Then the hydrolytic condensation of APES-PGE and APES-PGE2 was performed by dissolving 1 g of the corresponding silane in 1.5 ml tetrahydrofuran （THF）, adding water and eventually a catalyst （molar ratios: [H2O]/Si=3, [NaOH]/Si=0.05）, and heating at 50 ℃ for 24 h, allowing continuous evaporation of volatiles. The final products with branches containing hydroxyl groups were polyhedral oligomeric silsesquioxanes （POSS）. The products from two reactions were characterized by standard spectroscopic techniques, gel partition chromatography （GPC）, Fourier-transformed infrared spectroscopy （FTIR） and matrix-assisted ultraviolet laser desorption/ionization time-of-flight mass spectrometry （UV-MALDI-TOF MS）. Additionally, a narrow mass distribution of multifunctionalized POSS was shown by UV-MALDI-TOF MS and assignments of the MS peaks.

Extraction,Isolation and Structural Characterization of Polysaccharides from a Red Alga Gloiopeltis furcata

Three kinds of polysaccharides： GFW, GFH and GFA, were sequentially extracted from a red alga Gloiopeltisfurcata with 25℃ and 85℃ water, and 60℃ 4% NaOH water solution. Based on the defatted alga, the yields of the polysaccharide were 57.9%, 2.5% and 2.6%, respectively. Their monosaccharide compositions, average molecular weights and structural characters were determined by gas chromatography （GC）, high performance liquid chromatography （HPLC）, fourier transform infrared spectroscopy （FTIR） or ^13C-NMR spectroscopy. The results showed that GFW, GFH and GFA were all composed of D-galactose （Gal） and 3,6-anhydro-L-galactose （AnG）, and particularly GFA also contained xylose （Xyl）. The average molecular weights of GFW, GFH and GFA were 22.6 kD, 26.5 kD and 49.8 kD, respectively, with the respective sulfate content 31.2%, 25.1% and 22.7%. The data of FTIR and ^13C-NMR confirmed the sulfate ester location at C6 ofgalactose. It is concluded that all the three polysaecharides extracted from Gloiopeltisfurcata were sulfated galactans, two being sulfated-agarose, and one being xylose-containing sulfated galactan.

Preparation, characterization, and antifungal activity of hymexazol-linked chitosan derivatives

In this study, three hymexazol-linked chitosan derivatives （HML-CS） were synthesized and their structures confirmed by Fourier transform infrared and elemental analysis. Linkage ratios were measured by high performance liquid chromatography. The derivatives＇ antifungal activity against the plant pathogenic fimgi Rhizoctonia solani CGMCC 3.28 and Gibberella zeae CGMCC 3.42 were investigated at concentrations of 100, 200, and 400 mg/L. These HML-CS derivatives exhibited stronger antifungal activity than CS alone. HML-CS-1 showed the best antifizngal activity against G. zeae, whose antifimgal index was 65.9% at 400 mg/L, and also showed the best antifungal activity against R. solani, whose antifimgal index was 52.7% at 400 mg/L. This conjugation of CS and HML suggested the presence of synergistic effects between the moieties and indicated that these derivatives possessed great potential as novel fungicides and require further research for the development of applications in crop protection.

Optimization of Yield and Chemical Properties of Agar Extracted from Melanothamnus Somalensis from Oman Sea

The red seaweed Melanothamnus somalensis was investigated as potential economic source of agar. The effect of different conditions of alkali pre-treatment on chemical properties of agar was evaluated. Agar was extracted by various concentrations of NaOH （4%, 6% and 8%） and heated at different temperatures （70 ℃, 75 ℃ and 80 ℃） for different durations （2 h, 2.75 h and 3.5 h）. The yields-molecular weight （Mw） and sulfate contents of extracted agar were analysed and characterized by FTIR spectroscopy. The yield was significantly increased at these treatments from 23.29% to 30.86%. Mw studied by HPLC ranged from （.12.45 ± 0.21） × 10^5 to （8.60 ± 2.40） × 10^5 Da. FTIR bands show sulfate groups in C4 and C6 ofgalactose and no sulfate group were found on both C2 of galactose and C2 of 3,6-anhydrogalactose. All treatments showed a high sulfate content that ranged from 5.4% to 10.1%. These properties were found to be significantly affected by the alkali pre-treatment concentration （p 〈 0.05）. In conclusion, agar extracted in this study was considered acceptable for industrial application and the optimal conditions for extraction were found to be at 6% NaOH at 70 ℃ for 2 hours.

Nickel Catalyzed High-Pressure Hydrothermal Processing of Biomass for H2 Production

In this study, high-pressure hydrothermal processing of different biomass sources and products, which include cellulose, xylan, lignin, pine wood, paper waste, and waste lignin was performed at 200-275 ℃ in presence of NiSO4 catalyst. Biomass slurry was prepared in distilled water containing NiSO4, loaded in a high-temperature high-pressure reactor and heated to different temperatures. The reaction was continued for 120 min and during the reaction gas samples were withdrawn and analyzed using Chrompack capillary column on the gas chromatograph equipped with thermal conductivity detector. The analysis of gas samples revealed the presence of H2, CO2, CO, and CH4 gases. Increase in catalyst concentration from 3 wt% to 10 wt% has significantly increased the H2 generation. Absence of catalyst, however, generated almost negligible amount of H2. Among the biomass sources and products investigated here, xylan has yielded maximum amount of H2. The liquid samples were analyzed by high-performance liquid chromatography （HPLC） and Fourier transform infrared （FTIR） spectroscopy which revealed the presence of sugars along with the other intermediates.