新型表面活性剂改性硝酸铵的研究

选用阳离子表面活性剂、阴离子表面活性剂以及两种表面活性剂复合后的改性剂对硝酸铵进行表面处理,测定了改性前后硝酸铵的表面接触角、表面张力以及在特定温湿度条件下的吸湿率。结果表明,改性后硝酸铵的吸湿性得到了较好地改善,并得出复合型表面活性剂的改性效果最好,吸湿率下降了87.2%。     

阳离子型偶联表面活性剂改性硝酸铵性能研究

对阳离子型偶联表面活性剂膨化处理的改性硝酸铵进行了电镜扫描、孔径与孔容分布、粒径分布、比表面积、抗吸湿结块性及爆炸性能的实验研究，结果表明：同普通硝酸铵相比，阳离子型偶联改性硝酸铵的晶形不规则，富含气孔；比表面积大，可达3869．56cm^2／g；95％有效孔径处于介孔范围，有较小的粒径范围，主要分布在10～1000μm范围内；并且有良好的抗吸湿结块性，改性硝酸铵的吸湿率比普通硝酸铵的吸湿率降低约60％，抗压破坏力仅为普通硝酸铵的1／6，用其制得的粉状工业炸药具有更好的物理性能和爆炸性能。     

Gemini表面活性剂C12-3(OH)-C12·2Cl对膨化硝酸铵晶体性能影响的研究

本文通过对Gem in i表面活性剂C12-3(OH)-C12.2C l及其单体表面活性剂DTAB分别处理的膨化硝酸铵进行晶体接触角、表面能、比表面积、晶变特性、抗吸湿结块性及爆炸性能的实验研究,结果表明,同DTAB处理的膨化硝酸铵相比,C12-3(OH)-C12.2C l改性的膨化硝酸铵的晶体接触角较大、表面能较小、比表面积大,晶变热降低且晶变点后移,有良好的抗吸湿结块性,用其制得的粉状工业炸药具有更好的物理性能和爆炸性能。     

螯合型硝酸胺改性剂的合成及其应用研究

以钛酸酯偶联剂为起始原料,与丙二酸反应得到螯合型丙二酸钛酸酯,再发生酯交换反应,制备得到螯合型表面改性剂。通过FT-IR对相关化合物进行了结构表征,结果表明所得结构与预期产物的结构相一致。用螯合型钛酸酯改性剂对硝酸铵采用液相分离法改性,改性后硝酸铵颗粒表面有包覆层。与未改性的硝酸铵相比,改性硝酸铵的吸湿率下降了69.74%。     

表面活性剂和添加剂降低硝酸铵吸湿性研究

用复合表面活性剂和添加剂对硝酸铵进行表面处理，测定了硝酸铵的吸湿性，分析了降低硝酸铵吸湿性的理论原因。结果证明了复合表面活性剂和添加剂能有效降低硝酸铵的吸湿性。     

膨化硝酸铵的膨化过程研究

讨论了硝酸铵膨化敏化过程中体系水分、温度的变化情况和微气泡、孔的形成过程,研究发现专用表面活性剂在硝酸铵膨化敏化改性过程中起降低表面张力和起发泡剂的作用。     

微胶囊技术在硝酸铵改性中的应用

提出了用聚苯乙烯包覆硝酸铵制备硝酸铵微胶囊的新方法 ,采用电子能谱仪研究了包覆效果 ,并对包覆前后的硝酸铵进行吸湿性测量 ,分析了改性后的硝酸铵吸湿结块性降低的原因和机理。     

表面活性剂改善硝酸铵物化性能和爆炸性能的研究

用表面活性剂对硝酸铵进行溶化－真空结晶处理，得到一种含有许多微孔的片状膨松硝酸铵。研究了这种改性硝酸铵的物理化学特性和爆炸性能，介绍了用改性硝酸铵制成的几种粉状工业炸药的爆炸性能。     

聚苯乙烯包覆硝酸铵改善吸湿性的研究

采用相分离法制备了聚苯乙烯(PS)包覆硝酸铵(AN),研究了甲苯和正己烷体积比、聚苯乙烯与硝酸铵质量比、混合溶剂与硝酸铵配比、沉淀剂加入速度等因素对聚苯乙烯包覆硝酸铵性能的影响。用吸湿降低率评价聚苯乙烯对硝酸铵包覆程度。结果表明,聚苯乙烯包覆硝酸铵的较佳工艺条件为甲苯与正己烷体积比为1∶3,混合溶剂/AN=3.5 mL/g,室温,沉淀剂滴速10滴/min。包覆60目硝酸铵,PS质量分数为1.54%,包覆AN吸湿降低率75%。硝酸铵目数增大,达到相同吸湿降低率,PS用量显著增大。     

改性硝酸铵的工业制备方法及其性能

硝酸铵饱和溶液中加入表面活性剂辛基三甲基溴化铵，采用真空膨胀结晶技术工业制备一种新型改性硝酸铵，并介绍其性能特点。     

羟丙基三甲基氯化铵壳聚糖在化妆品中的应用研究

用2，3-环氧丙基三甲基氯化铵对壳聚糖进行改性，采用不同反应条件制备了一系列不同取代度的羟丙基三甲基氯化铵壳聚糖（HACC），通过红外光谱，核磁共振光谱对结构进行表征，IR谱图证实以N上取代为主。研究了产物的取代度，吸湿与保湿性、抗菌性，pH稳定性，与表面活性剂的配伍性。     

新型两性壳聚糖衍生物的制取及应用研究

用氯乙酸和2,3-环氧丙基三甲基氯化铵对壳聚糖进行改性,采用不同反应条件制备了一系列不同取代度的O-羧甲基-N-羟丙基三甲基氯化铵壳聚糖。通过红外光谱对结构进行表征,IR谱图分析证实羧甲基以0位上为主,季铵盐阳离子基以N位上取代为主。研究了产物的取代度、吸湿保湿性、抗菌性、pH稳定性及与表面活性剂的配伍性,结果表明具有良好的吸湿保湿性。     

岩石膨化硝铵炸药的生产工艺和质量控制

岩石膨化硝铵炸药是一种新型无梯粉状炸药,它是由膨化硝酸铵、木粉和复合油相组成,其中膨化硝酸铵是经过表面活性技术处理的自敏化改性硝酸铵。文中介绍了岩石膨化硝铵炸药的生产工艺,详细讨论了影响膨化硝酸铵质量和岩石膨化硝铵炸药质量的因素。     

改性硝酸铵研究进展及其发展方向

从粒状硝酸铵的问世和发展、抗硬化结晶粉末硝酸铵和不破乳松散性结晶硝酸铵的研究、用于膨化炸药的膨化硝酸铵研制、用于无梯炸药的敏化改性硝酸铵的研究、钝化或防爆硝酸铵的开发、液体硝酸铵在炸药中的应用、改性多孔粒状硝酸铵的研究等方面概述了我国改性硝酸铵的研究成果。开发高性能多孔硝酸铵和防爆的农用硝酸铵及其下游产品,是我国改性硝酸铵今后主要的发展方向。     

硝酸铵膨化机理研究

简介了新型粉状工业炸药——岩石膨化硝铵炸药配方及特性,提出了硝酸铵膨化机理,讨论了空白膨化及表面活性剂膨化硝酸铵的影响因素及其结果。     

Phosphonium‐based layered silicate—Poly(ethylene terephthalate) nanocomposites: Stability,thermal and mechanical properties

PET‐clay nanocomposites were prepared using alkyl quaternary ammonium and phosphonium modified clays by melt‐mixing at 280°C using a micro twin screw extruder. The latter clays were prepared by synthesizing phosphonium surfactants using a simple one‐step method followed by a cation exchange reaction. The onset temperature of decomposition (T_onset) for phosphonium clays (>300°C) was found to be significantly higher than that of ammonium clays (around 240°C). The clay modified with a lower concentration (0.8 meq) of phosphonium surfactant showed a higher T_onset as compared to the clay modified with a higher concentration (1.5 meq) of surfactants. Nanocomposites prepared with octadecyltriphenyl phosphonium (C18P) modified clay showed a higher extent of polymer intercalation as compared with benzyltriphenylphosphonium (BTP) and dodecyltriphenylphosphonium (C12P) modified clays. The nanocomposites prepared with ammonium clays showed a significant decrease in the molecular weight of PET during processing due to thermal degradation of ammonium surfactants. This resulted in a substantial decrease in the mechanical properties. The molecular weight of PET was not considerably reduced during processing upon addition of phosphonium clay. The nanocomposites prepared using phosphonium clays showed an improvement in thermal properties as compared with ammonium clay‐based nanocomposites. T_onset increased significantly in the phosphonium clay‐based nanocomposites and was higher for nanocomposites which contained clay modified with lower amount of surfactant. The tensile strength decreased slightly; however, the modulus showed a significant improvement upon addition of phosphonium clays, as compared with PET. Elongation at break decreased sharply with clay. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Studies on properties of softwood (Ficus hispida)/PMMA nanocomposites reinforced with polymerizable surfactant-modified nanoclay

Soft wood (Ficus hispida) was chemically modified by impregnation of methyl methacrylate monomer, glycidyl methacrylate (GMA), a cross-linking agent, and montmorillonite (MMT) using catalyst heat treatment. MMT was modified by using a polymerizable surfactant 2-acryloloxy ethyl trimethyl ammonium chloride (ATAC) and a mixture of surfactants ATAC and cetyl trimethyl ammonium bromide (CTAB) in a molar ratio of (1:1). A comparative study on different properties of the prepared wood polymer nanocomposite (WPNC) based on impregnation of intercalating mixture containing MMA/GMA/clay modified by both the surfactants (ATAC and CTAB) and MMA/GMA/clay modified by only surfactant ATAC were done. FTIR, XRD, and TGA studies were employed for the characterization of clay and WPNC. WPNC prepared by using combined surfactant-modified clay along with MMA/GMA exhibited improved dimensional stability, chemical resistance, thermal stability, mechanical properties, and lower water uptake than that of WPNC prepared by using single surfactant-modified clay and MMA/GMA system.     

含硝态氮的国产化肥少了

我国生产的氮肥数量巨大,但含硝态氮的化肥所占比例很小,这不利于化肥的合理施用.铵态氮和硝态氮作为植物的氮源,两者基本上是等效的,要根据作物和土壤条件合理施用.我国应当适当增加含硝态氮化肥的生产.第一,要对硝酸铵进行改性,使之不能再制造炸药;第二,要消除认为用了硝态氮肥就不能生产绿色食品的错误认识.     

Photopolymerization kinetics of poly(acrylate)-clay composites using polymerizable surfactants

Photopolymerization kinetics of polymer-clay nanocomposite systems utilizing polymerizable quaternary ammonium surfactants as dispersants were systematically investigated to determine the effects of surfactant type and clay morphology on polymerization behavior. For these studies, either polymerizable surfactants were mixed into a clay-monomer system or the surfactants were ionically anchored to clay surfaces and added to the monomer for in situ photopolymerization. Higher photopolymerization rates are observed with increasing polymerizable surfactant concentration, while no significant change or decreases in polymerization rate occur with incorporation of non-polymerizable surfactants. The higher rates observed for polymerizable surfactant systems are due to lower apparent termination rate parameters stemming from immobilization of the surfactants. For clay that is modified with ionically bonded quaternary ammonium surfactants, polymerization rates decrease in both polymerizable and non-polymerizable organoclay systems with increasing concentration, but this decrease is much smaller when polymerizable organoclays are utilized. For the same organoclay concentration, higher polymerization rates and double bond conversions result with increasing polymerizable surfactant concentration via cation exchange. Significant increases in polymerization rate also occur with increasing degree of clay exfoliation.