尿素系复肥的生产与开发

我国土壤由于氮肥用量过大,土壤中的氮磷钾及微量元素比例失调,搭配不当,已引起了人们的高度重视,用肥观念正在改变,对化肥已有更新,更高的要求。新型,高浓度复肥被列“九五”期间重点推广项目,国家加大了高浓度化肥的投资,国产高浓度化肥所占比较将逐年增加。在化肥总体销售形势不好的情况下,高浓度化肥,尤其是复肥销售情况相对较好,而碳铵,普钙等单一,低浓度化肥积压严重,应用新技术,开发生产新型,高浓度复混肥势在必行。     

The use of citric acid in the production of polyols for rigid PUR-PIR foams

The article describes the method of obtaining new, cheaper compounds which can substitute polyols in the production of rigid polyurethane-polyisocyanurate foams (PUR-PIR). Rigid PUR-PIR foams were synthesized, using newly obtained tree compounds (citrates with hydroxyl groups): obtained with using catalyst (T-2-HHT + K), without catalyst (T-2-HHT) and (T-5-HHT). New compounds (T-2-HHT + K, T-2-HHT, T-5-HHT) were prepared from citric acid (1 mol) and glycols, respectively: butane-1.2-diol (3 mol and excess of 30 cm³), butane-1.2-diol (3 mol), pentane-1.5-diol (3 mol) by the esterification reaction in the solution. The industrial Rocopol 551, used as polyol, was gradually substituted for the new compounds in the polyol premix in new foams. The three series of rigid polyurethane-polyisocyanurate foams based on T-2-HHT + K, T-2-HHT, T-5-HHT have been synthesized (F1–F16) and W foam without new compound. Its properties have been determined according to the standards. It has been shown that the addition of T-2-HHT + K, T-2-HHT, T-5-HHT to the foams affects the foams’ density. The influence of the abovementioned compounds on foams’ flammability, thermal properties and others was examined. A decrease in foams’ brittleness by 6.9 % and in oxygen index by 24 % was observed. The examined retention was in the range of 80.9–96.5 %.     

Synthesis and studies of phosphorus-containing polyurethane foams based on tetrakis(hydroxymethyl) phosphonium chloride derivatives

A phosphorus- and nitrogen-containing polyl is prepared by condensing tetrakis(hydroxymethyl)phosphonium chloride with diethanol amine in aqueous medium. The newly synthesized polyol-bis(hydroxymethyl)-N, N-bis(2-hydroxyethyl)aminomethylphosphine oxide (AMPO) is used in the preparation of rigid polyurethane foams with a various phosphorus content. With the view to comparing their properties, polyurethane foams are also prepared on the basis of the commercially available flame retardant diethyl-N, N-bis(2-hydroxyethyl)aminomethylphosphonate (Fyrol 6). The flammability, thermal stability, and thermoechanical properties of the polyurethane foams obtained are studied. A certain difference in the behavior of the two modified polyurethane foams is observed. The polyurethane foams with AMPO exhibit a slight increase in the resistance to combustion (oxygen index) and a noticeable improvement in the thermal and mechanical properties. These differences probably arise as a result of structural and functional differences between the two types of phosphorus-containing flame retardants.     

Lignin-derived macroporous carbon foams prepared by using poly(methyl methacrylate) particles as the template

An efficient route for the synthesis of lignin-derived carbon foams by thermal decomposition of an organic colloid template is described. Lignin, resorcinol, and formaldehyde were reacted by polycondensation into a crosslinked phenolic resin network in the presence of colloidal poly(methyl methacrylate) microspheres as the sacrificial template. Subsequently, carbonization was carried out at 800 °C to fabricate carbon foams with porous structural frameworks. Lignin was used as an excellent candidate for replacing resorcinol or other phenolic substances in the phenolic resin due to its high carbon yield above 50%. The prepared lignin-derived carbon foams had partially open cell structures. The carbon foams had the bulk density and porosity of 0.37–0.60 g/mL and 68.5–82.8%, respectively. Furthermore, the addition of lignin increased the mechanical properties strength of carbon foams.     

Effect of selected boroorganic compounds on thermal and heat properties of rigid polyurethane–polyisocyanurate foams

The effects of three selected borates {tri(hydroxypropyl), tri[(3‐chloro‐2‐hydroxy‐1‐propoxy)‐1‐methylethyl], tri[(3‐chloro‐2‐hydroxy‐1‐propoxy)propyl]} on the heat and thermal properties of rigid polyurethane–polyisocyanurate foams was studied. Increasing the amount of tri(hydroxypropyl) borate and tri[(3‐chloro‐2‐hydroxy‐1‐propoxy)propyl] borate in the foam composition from 0.1 to 0.4 chemical equivalents caused an increase in the softening point, the temperature of the first decrement of foam mass, the extrapolated temperature of the main decrement of the foam mass, and the temperature of the highest rate of the mass decrement. When tri[(3‐chloro‐2‐hydroxy‐1‐propoxy)‐1‐methylethyl] borate was added to the foam compositions, the softening point decreased but the temperatures characterizing their thermal resistance were higher in comparison with the standard foam. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 768–771, 2006     

Effect of selected boroorganic compounds on thermal and heat properties of rigid polyurethane–polyisocyanurate foams

The effect of selected borates [i.e., tri(hydroxypropyl) borate (BTHP), tri[(3‐chloro‐2‐hydroxy‐1‐propoxy)propyl] borate (BTClHPP), and tri[(3‐chloro‐2‐hydroxy‐1‐propoxy)‐1‐methylethyl] borate (BTClHPME)] on the heat and thermal properties of the rigid polyurethane–polyisocyanurate foams was investigated. Increasing amounts of BTHP and BTClHPP in the foam composition, from 0.1 to 0.4 of chemical equivalent, caused increases in the softening point, the temperature of the first decrement of foam mass, the extrapolated temperature of the main decrement of the foam mass, and temperature of the highest rate of the mass decrement. In the case when BTClHPME was added to the foam compositions, the softening point decreased but temperatures characterizing their thermal resistance were higher compared to that of standard foam. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 400–403, 2005     

羟甲基木质素磺酸钠对聚丙烯酰胺弱凝胶的改性

以聚丙烯酰胺(HPAM)为主剂,采用两步碱催化法合成水溶性酚醛树脂作交联剂,羟甲基木质素磺酸钠(HSL)作添加剂,制备HPAM弱凝胶。探讨HPAM浓度、交联剂用量、HSL用量、成胶温度、体系pH对成胶黏度的影响。结果表明,较适宜的成胶条件为:HPAM浓度0.3%,交联剂用量0.4%,HSL用量0.03%,pH为6～9,温度70～110℃。该体系所形成的弱凝胶具有网格密集、大小均一的三维网络结构,具有良好的抗盐及抗剪切性能。     

羟甲基木质素磺酸钠对聚丙烯酰胺弱凝胶的改性

以聚丙烯酰胺(HPAM)为主剂,采用两步碱催化法合成水溶性酚醛树脂作交联剂,羟甲基木质素磺酸钠(HSL)作添加剂,制备HPAM弱凝胶。探讨HPAM浓度、交联剂用量、HSL用量、成胶温度、体系pH对成胶黏度的影响。结果表明,较适宜的成胶条件为:HPAM浓度0.3%,交联剂用量0.4%,HSL用量0.03%,pH为6～9,温度70～110℃。该体系所形成的弱凝胶具有网格密集、大小均一的三维网络结构,具有良好的抗盐及抗剪切性能。     

Microstructure and properties of epoxy foams prepared by microwave

In this article, epoxy foams comprised of diglycidyl ether of bisphenol‐A (DGEBA) based epoxy resin E₃₁ and E₅₁, polyamide resin, and water were prepared by microwave irradiation method. The structure and properties of epoxy foams were analyzed by FTIR, TGA, SEM, and DMA methods. The density and compressive performance of epoxy foams was also determined. The results indicated that the epoxy foams had excellent compressive performance and the preparation of epoxy foam by microwave irradiation was high efficiency and convenient. The composition has great effect on density, foam structure, dynamical mechanic performance, and thermal degradation behavior of epoxy foams. The epoxy foam with density from 0.08 g cm^?3 to 1.05 g cm^?3 can be obtained by varying ratio of E₅₁ and E₃₁ to control the viscosity of mixtures. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Solid‐state characterization and the thermal properties of stereoregular poly(vinyl chloride) prepared by urea clathrate polymerization

The solid‐state characterization of highly stereoregular poly(vinyl chloride) (PVC) prepared by urea clathrate polymerization was carried out by using various instrumental analyses. The structural differences of PVC appeared most remarkably in solubility to organic solvents, IR, WAXD, and solid‐state ¹³C‐NMR spectra. The value of the glass transition temperature (T_g) was about 90°C, not as high as expected, although its detection was quite difficult. The thermal stability was poor, as evidenced by the easy discoloration of this polymer by heat treatment, which was related to the absence of a termination reaction. Dynamic ESR spectra in the solid state clearly indicate that the radical formation occurs at such a low temperature as 160°C in the initial degradation stage. The degradation characteristics of urea clathrate PVC were critically discussed. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 2820–2825, 1999     

2,2-二羟甲基丁酸合成工艺研究

以正丁醛、甲醛和双氧水为主要原料,经羟醛缩合、氧化反应制备2,2-二羟甲基丁酸,考察了缩合、氧化反应条件。结果表明,最佳缩合反应条件为:正丁醛∶甲醛∶双氧水=1∶2.4∶1.4(摩尔比),缩合反应温度35℃左右,缩合反应时间6 h;氧化反应条件为:温度80℃左右,反应时间6 h。反应液采用离子交换→真空浓缩→溶剂结晶→重结晶工艺处理,2,2-二羟甲基丁酸产品总收率大于40%。     

Oxidation of 2,3-Bis(hydroxymethyl)indole

Oxidation of 2,3-bis(hydroxymethyl)indole ( 1 ) with MnO₂ yields as intermediate 3-formyl-2-hydroxymethylindole ( 2 ) and finally 2,3-diformylindole ( 3 ). The structure of 2 was proved by both chemical methods and ¹³C n.m.r. spectra. Use of DMSO acetic anhydride mixture as the oxidative agent, however, yields the 3,3′-diindolylmethane derivative 4 , instead of 2 or 3 .     

硫酸脲氨化造粒复合肥生产技术

介绍硫酸脲氨化造粒复合肥的生产原理、工艺流程、生产设备,以及生产技术特点.在转鼓蒸汽造粒复混肥生产装置上采用硫酸脲氨化造粒技术改造生产复合肥,投资少,产品物性好,节能效果显著.     

Impact of key deposition parameters on the morphology of silver foams prepared by dynamic hydrogen template deposition

The potentiostatic deposition of porous Ag foams from a new stable thiocyanate based bath using hydrogen bubbles as a dynamic template during deposition was investigated. The influence of the electrolyte content, deposition potential and deposition time on the micro- and nanoscale morphology of the Ag form was examined. The formation of three main morphological forms on the nanoscale level: dendrites, a framework of identical particles, and agglomerates of inhomogeneous particles with big Ag granules distributed on the foam surface, was demonstrated by the analysis of the scanning electron microscopy (SEM) data. The quality of the structures obtained was examined by energy dispersive X-ray spectroscopy (EDS) and X-ray diffractometry (XRD). It was found that the experimental parameters had a huge effect on the morphology of Ag on both the micro- and nanoscale. The structures with the most efficient geometry from the technological point of view were obtained with the correct combination of parameters, viz. high concentrations of NH₄⁺ and Ag⁺ in conjunction with a sufficient deposition potential and time. Foams with roughness factors as high as 1100 were obtained, showing a high geometrical area normalized double-layer capacitance and relatively high gravimetric capacitance of 22 mF cm⁻² and 2.4 F g⁻¹, respectively.     

A biocompatible synthesis of gold nanoparticles by Tris(hydroxymethyl)aminomethane

Gold nanoparticles'' novel properties are widely realized in catalysis, plasmonics, electronics, and biomedical applications. For biomedical application, one challenge is to find a non-toxic chemical and/or physical method of functionalizing gold nanoparticles with biomolecular compounds that can promote efficient binding, clearance, and biocompatibility and to assess their safety to other biological systems and their long-term effects on human health and reproduction. In the present study, we describe a new method by using Tris(hydroxymethyl)aminomethane (Tris), a widely used buffer solvent of nucleic acid and proteins, as the reducing agent for synthesizing gold nanoparticles by one step. It is found that Tris carries out the reduction reactions in relatively mild conditions for biomacromolecules. Particularly, it can be used to modify the DNA during the process of preparation of gold nanoparticles. The morphology and size distribution of gold nanoparticles are consistent and were confirmed by many different approaches including dynamic light scattering (DLS), UV-visible (UV-vis) spectrophotometry, atomic force microscopy (AFM), and transmission electron microscopy (TEM).     

超声波照射合成双二苯基膦烷烃的研究

以锂片、三苯基膦、二氯代烷烃为主要原料,合成了Ph2P(CH2)nPPh2(n=1~6)系列双二苯基膦烷烃化合物。该类化合物是四电子供体,具有较强的电子给与能力,是较好的桥连和螯合配体,和许多金属离子能形成较稳定的配合物。结果表明,反应在高纯氮气保护下,采用超声波照射,反应温度控制在10℃以下,产品收率提高了30%,经元素分析、红外光谱和熔点测定等手段,证明产品的化学结构同理论吻合。     

橄榄石酸溶制备超细二氧化硅改性研究

橄榄石酸溶制备超细二氧化硅工艺简单、生产成本低。但是制备的超细二氧化硅表面羟基键合严重、分散性能差、易团聚。利用硅烷偶联剂对橄榄石酸溶制备的超细二氧化硅进行改性研究。采用单因素实验考察了硅烷偶联剂品种、改性时间、改性温度及改性剂用量等因素对超细二氧化硅改性效果的影响。实验结果表明,在硅烷偶联剂KH-550加入量为6 mL/g、改性时间为5 h、改性温度为75 ℃条件下,制备的超细二氧化硅表面的羟基数量减少至2.08×10 ²⁰ 个/g、接枝率为8.35%、接触角达到101.51°,极大地提高了超细二氧化硅的表面疏水性。     

尿素过磷酸钙复肥生产工艺

介绍了尿素过磷酸钙（USP）复肥的主要生产工艺过程及条件,认为USP复肥是普通过磷酸钙（SSP）生产厂理想的升级产品。     

四羟甲基硫酸鳞的合成及测定研究

以黄磷、锌粉、硫酸和甲醛为原料，成功合成了四羟甲基硫酸鳞（THIS），详细探讨了不同合成条件对THIS产率的影响，并通过正交实验确定最佳合成工艺为：黄磷：锌粉：硫酸：甲醛=1：2．5：7．5：5（摩尔比），反应温度为85℃，反应时间为6h。建立了测定其活性物含量的离子交换法，测得THIS的含量为79．20％。用36％乙酸对产品进行重结晶，成功得到了THIS针状晶体。     

四羟甲基硫酸鏻的合成及测定研究

以黄磷、锌粉、硫酸和甲醛为原料,成功合成了四羟甲基硫酸鏻(THPS),详细探讨了不同合成条件对THPS产率的影响,并通过正交实验确定最佳合成工艺为:黄磷∶锌粉∶硫酸∶甲醛=1∶2.5∶7.5∶5(摩尔比),反应温度为85℃,反应时间为6 h。建立了测定其活性物含量的离子交换法,测得THPS的含量为79.20%。用36%乙酸对产品进行重结晶,成功得到了THPS针状晶体。