Supermacroporous polydivinylbenzene cryogels with high surface area: Synthesis by solvothermal postcrosslinking and their adsorption behaviors for carbon dioxide and aniline

Cryogels are supermacroporous but restricted by lack of surface area in utilization to date. We here propose a method for fabrication of supermacroporous polydivinylbenzene (PDVB) cryogels with high surface area by redox-initiated cryopolymerization combined with solvothermal postcrosslinking technique. The PDVB precursor cryogels are prepared by redox-initiated cryopolymerization, followed by postcrosslinking of residual double bonds to form hypercrosslinked cryogels under solvothermal conditions. The hypercrosslinked cryogels maintain the original supermacroporosity and display very high surface area up to 1462 m² g⁻¹. We demonstrate the utilization of the resultant cryogel in uptake of carbon dioxide (7.9 wt % at 1 bar and 62.2 wt % at 25 bar, respectively) and uptake of aniline (333.3 mg g⁻¹ at room temperature) from aqueous solutions. The adsorption behaviors of aniline on the hypercrosslinked cryogels are found to follow Langmuir model as well as Freundlich model in equilibrium adsorption and to follow pseudo-second-order model in kinetic adsorption, respectively. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47716.     

阳离子交换型连续床用超大孔晶胶的制备

采用原位接枝法,将3-烯丙氧基-2-羟基-1-丙磺酸钠(AHPSA)接枝到聚丙烯酰胺基晶胶基质孔隙内表面,制备得到了阳离子交换型连续床用的带磺酸基超大孔晶胶介质.通过脉冲示踪法测量停留时间分布(RTD),得到了晶胶介质的理论等板高度(HETP).通过测量一定压差下流经晶胶床柱的液量,得到晶胶介质的渗透率.用溶菌酶作为模型蛋白测量晶胶介质的吸附容量.考察了单体浓度、接枝反应时间等反应条件对晶胶介质的HETP、渗透率、蛋白质吸附容量等性能的影响.结果表明:接枝AHPSA的阳离子交换晶胶介质的HETP基本不受接枝反应时间和单体浓度的影响,其渗透率随接枝反应时间增大略有减小,其对溶菌酶的吸附容量与接枝单体的浓度成正比,受接枝反应时间的影响较小.     

一步沉淀法制备表面疏水性纳米氢氧化镁

以油酸为改性剂,采用化学沉淀法一步制备了表面疏水性的氢氧化镁纳米粒子,研究了合成条件对氢氧化镁团聚和形态的影响。XRD证明所制备的氢氧化镁纯度高,平均晶粒尺寸为16nm;FT-IR表明油酸分子已键合在纳米氢氧化镁表面;TEM显示,所制备的纳米氢氧化镁表面形态呈针状或片状,在甲苯中分散性好。计算得到制备的纳米氢氧化镁活化指数可达98.9%,粒子表面呈疏水性。     

Supermacroporous hybrid polymeric cryogels for efficient removal of metallic contaminants and microbes from water

A supermacroporous cryogel column of chitosan-dimethylaminoethyl methacrylate (DMAEMA)-magnetite has been synthesized. The cationic and magnetic properties of chitosan/DMAEMA and magnetite, respectively, allow the adhesion of metals and microbes to the matrix. The large interconnected pores (20–100 µm) with porosity greater than 85% of the cryogels facilitate fast water movement. At lab scale (approximately 2 mL bed volume), static binding capacity of 100% (load: 4.5 ppm arsenic and 2300 ppm chromium) and dynamic binding capacity of 65% for arsenic (load: 58 ppm) was observed. The binding capacity at pilot scale (approximately 300 mL bed volume) was found to be 11.5 mg arsenic and 14.22 mg chromium. There was 100% binding of microbes (Escherichia coli and Streptococci) both at lab and pilot scale. The results were propitious and indicated the suitability of cryogel filter as a single device for the removal of arsenic, chromium, and microbes in field samples.     

双功能基团整体晶胶的层析性能与床层非均匀性研究

超大孔晶胶在生物技术领域有广泛的应用前景,研究具有新型功能基团的晶胶介质及其性能具有重要意义。今以N,N,N-三甲基乙烯基苯甲氯化铵为接枝单体,通过接枝修饰,制备得到具有离子交换和疏水双功能基团的聚丙烯酰胺基整体晶胶新介质,并对其基础和层析性能及床层非均匀性进行了研究。将晶胶床柱沿轴向分为四段,分别对其渗透率、孔隙率及在不同流速下的蛋白质吸附层析和轴向分散性能进行了实验研究。结果表明,该晶胶对牛血清蛋白的吸附容量随p H和流速而变化;在2 cm·min-1的流速下,当p H为5.0时最大吸附容量达7.3 mg·m L-1晶胶柱,且吸附容量随流速增大而略有减小。沿床层轴向由顶到底晶胶的基础性能参数和吸附容量呈现差异性,在流速1~6 cm·min-1下其平均蛋白质吸附容量分别为2.41、2.14、2.58和2.57 mg·m L-1晶胶,相同流速下各段吸附容量间的差异达9.33%~16.15%;其渗透率和流速1~10 cm·min-1等板高度等基础性能参数间的相对差异达6.46%和21.05%。     

Synthesis and Characterization of Hydrophobic TMES/TEOS Based Silica Aerogels

The experimental results on the effect of adding trimethylethoxysilane (TMES) as a co-precursor on the hydrophobicity and physical properties of tetraethoxysilane (TEOS) based silica aerogels, are reported. The molar ratio of TEOS, ethanol (EtOH), water (0.001 M oxalic acid catalyst) was kept constant at 1:5:7 respectively, while the molar ratio of TMES/TEOS (A) was varied from 0 to 0.6. It has been observed that as the A value increases, the gelation time increases. The hydrophobicity was tested by measuring the contact angle, and the surface chemical modification was confirmed by the FTIR spectroscopy studies. The thermal stability of the hydrophobic aerogels was studied in the temperature range from 25 to 800°C. The hydrophobic nature of the aerogel could be maintained up to a temperature of 287°C and above this temperature the aerogels become hydrophilic. The bulk density and the optical transmittance of the aerogels have been found to decrease with increase in A value. The aerogels have been characterized by Fourier transform infrared spectroscopy (FTIR), Optical transmittance, Scanning electron microscopy (SEM), Differential thermal analysis (DTA) and Thermogravimetric analysis (TGA), and Contact angle measurements.     

疏水性L-酒石酸正戊酯的合成

以甲苯作溶剂,L 酒石酸、正戊醇为原料,在对甲苯磺酸的催化下,n(正戊醇)/n(L 酒石酸)=2 8,加热回流,温度控制在130～135℃,反应时间1h,合成了疏水性L 酒石酸正戊酯。折光率:n20D=1 4520,沸点:198～201℃,酯化率>99%,收率达78 4%。     

乙酸法乙酰丙酮的合成及应用

乙酰丙酮主要用于医药及中间体的合成，有着极其广阔的用途。本文介绍了乙酰丙酮的性能、用途、制备方法及乙酸法合成乙酰丙酮的工艺路线。     

吡啶催化合成乙酰水杨酸的研究

用吡啶催化剂,以水杨酸和乙酸酐为原料合成乙酰水杨酸.结果表明,当水杨酸用量为2.0g,乙酸酐用量为5.9 mL,吡啶用量为水杨酸质量的5%时,80℃反应30min,纯化乙酰水杨酸收率可达80.2%,且吡啶是合成乙酰水杨酸的优良催化剂.     

碳酸钙疏水改性及性能表征

采用单一改性剂油酸、硬脂酸、二甲基硅油及复合改性剂对碳酸钙颗粒进行疏水改性。介绍了改性碳酸钙的作用机理。探讨了改性剂种类和加入量对碳酸钙颗粒表面疏水程度的影响,并通过活化度表征疏水程度。采用红外光谱仪表征改性前后碳酸钙的结构,说明改性剂被引入到了碳酸钙颗粒表面上;采用Zeta电位仪测定改性前后碳酸钙随pH变化的Zeta电位,得知改性碳酸钙的Zeta电位受pH影响比较大;采用激光粒度仪测定改性前后碳酸钙的粒径,得知改性碳酸钙比未改性碳酸钙的平均粒径小,且其分散稳定性要优于未改性碳酸钙。该研究也提供了随改性剂种类和加量变化来调整颗粒表面疏水程度的方法,有一定实际意义。     

对硝基乙酰苯胺的合成研究

以对硝基苯胺、乙酸酐和乙酸为原料合成对硝基乙酰苯胺。考察了反应物物质的量配比、乙酸用量、反应温度、反应时间对对硝基乙酰苯胺反应收率的影响,利用正交发计选出影响产品收率的主要因素,并对丰要影响因素进行了单因素的详细研究,找出最佳合成条件。反应收率99．12％（高效液相色谱测定）。产品经红外光谱、^1H—NMR和元素分析证实为目标产物。该方法反应条件温和,操作简便,收率高。     

Hydrophobic recovery behavior of PMMA and PEA ionomers treated with PSII

The surfaces of poly(methyl methacrylate) (PMMA)‐based and poly(ethyl acrylate) (PEA)‐based ionomers were treated either with plasma or with plasma source ion implantation (PSII), and their hydrophobic recovery behavior was studied by measuring water contact angles. It was found that the hydrophobic recovery of the plasma‐treated and PSII‐treated surfaces of PMMA ionomers was much slower than that of the acid‐form copolymers. This was due to the presence of hydrophilic ionic groups on the ionomer surface. In addition, in the case of the PMMA ionomers, a slow hydrophobic recovery behavior for a long period of time was observed. In the case of the PEA ionomer, the water contact angle values were found to be larger than those for the PMMA ionomers. When the contact angle values of the PMMA and PEA ionomers were compared to those of polystyrene (PS) ionomers, it was found that the order of ionomers showing higher angle value at comparable aging time was as follows: PS ionomer > PEA ionomer > PMMA ionomer. This was due to the difference in polarity and matrix glass transition temperature of the ionomers. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3100–3106, 2003     

C1化学产品合成醋酸的研究

近年来醋酸合成方面的研究取得了很大的进展,其中包括甲醇羰基化、合成气一步合成醋酸、CO2加氢生成醋酸,CO2与甲烷的在等离子体状态下合成醋酸等。本文对C1化学在醋酸合成开发研究中的进展进行了论述。     

以酸活化膨润土催化合成阿司匹林

以水杨酸和乙酸酐为原料,在自制酸化膨润土催化下合成了阿司匹林;探讨了催化剂的结构特征及最佳催化条件。结果表明：酸化膨润土对阿司匹林的合成具有良好的催化活性;在最佳工艺条件下,收率可达：90．44％。     

乙酸法合成N-乙酰吗啉

以吗啉和乙酸为原料合成N-乙酰吗啉,考察了原料配比、反应温度和带水剂对反应的影响。试验结果表明,采用带水剂可使N-乙酰吗啉的收率明显提高,在加入10%带水剂、反应温度为40~145°C和原料配比n(乙酸)∶n(吗啉)/摩尔比为0.95下,N-乙酰吗啉的收率91.5%。反应产物经减压蒸馏后可得到大于98.5%的高纯度N-乙酰吗啉。     

3-二甲氨基甲基吲哚的合成工艺研究

用吲哚、二甲胺、甲醛、冰醋酸为原料合成3-二甲氨基甲基吲哚,最佳反应条件:配料比nC8HzN:n(CH)_3NH:nHCHO:nCH3COOH=1:1:1:2.5。在5℃时,二甲胺与冰醋酸混合均匀,再加入甲醛,吲哚,温度升至30℃,反应7小时。得到的液体冷至5℃,加入NaOH至pH=11,析出晶体。粗品水洗至pH=8,丙酮重结晶,干燥得产品。熔点:133.4℃,纯度:98％,以吲哚计算的收率84.5％。     

取代苯氧乙酸的合成及其表征

取代苯氧乙酸为合成新型农药的中间体，根据苯环上取代基类型的不同采用不同够合成方法进行合成，具有针对性强、产率高、反应时间短、操作简单、易纯化的优点．目标化合物的结构经元素分析和^1HNMR确证．     

Synthesis of Diorganotin Esters of 5-Bromonicotinic Acid: X-ray Crystal Structure of Polymeric 5-Bromonicotinatodiorganotin

Two types of diorganotins [R₂Sn(OCOC₅H₃N-3-Br-5)₂] _n and {[R₂Sn(OH₂)(OCOC₅H₃N-3-Br-5)₂]₂} _n (R= Me, n-Bu, Ph, n-Oc), are prepared from 5-Br-omonicotinic acid and diorganotin oxides. All the compounds, 1–8, are characterized by elemental analysis as well as IR and ¹H-NMR spectroscopy. The crystal structures of [R₂Sn(OCOC₅H₃N-3-Br-5)₂] _n (2) and {[R₂Sn(OH₂)(OCOC₅H₃N-3-Br-5)₂]₂} _n (8) were determined by single crystal X-ray diffraction. In compound 2, each carboxylate moiety of 5-Br-omonicotinic acid is involved in coordination to one Sn atom via two O-atoms, and the N-atom of one pyridine-ring coordinates to the neighboring Sn atom which leads to a polymeric chain. And the N-atom of the other pyridine-ring is dissociative. In compound 8, the compound proves to be dinuclear macrocyclic compounds with 5-Br-omonicotinic acid bridging the adjacent tin atoms with a 12-member ring. The hydrogen bonds ( ) are observed in the compound 8. These intermolecular hydrogen bonds form another ring, and lead to a polymeric chain in the lattice at the same time. An erratum to this article can be found at     

DMAc促进乙酰苯胺的合成

在N,N-二.甲基乙酰胺(DMAc)和CH2Cl2体系中,乙酸与SOCl2在0℃下反应20 min,制得的乙酰氯不经提纯直接与加入的苯胺在25℃下反应5h,得到了一系列取代乙酰苯胺化合物.优化条件下,反应产率为83％～ 97％.目标化合物的结构经1HNMR、13CNMR、IR和MS确证,提出了DMAc协同促进乙酰苯胺合成反应的可能机理.     

双乙酸钠的合成与发展展望

介绍了双乙酸钠的性质，在食品、饲料等方面的应用拓展，生产发展。展望了市场前景，阐述了新的合成工艺。