淀粉硫酸酯复合工艺制备

以天然淀粉为原料，采用半干法酯化、交联复合工艺制备了具有抗凝血活性、低流度的硫酸酯淀粉钠，解决了硫酸化淀粉严重降解的难题，讨论了交联对产品流度及抗凝血活性的影响。     

The Use of a Eutectic Mixture of Olive Pomace Oil Fatty Amides to Easily Prepare Sulfated Amides Applied as Lime Soap Dispersants

Sulfated diethanolamides of fatty acids are known to be effective lime soap dispersing agents. However, their preparation from fatty acids via fatty amides requires the use of organic solvents due to the high viscosity of both fatty amides and sulfated fatty amides. This study shows that the preparation of sulfated fatty amides is relatively easy when using olive pomace oil as the raw material. The latter, is converted into sulfated fatty amides by performing the following steps: saponification, hydrolysis, esterification, amidation, and sulfation. In the final step, the mixture obtained has sufficient fluidity, due to its high linoleic acid amide content, to obviate the use of organic solvents, as usually suggested in the literature. Characterization of the product was carried out by chemical analyses, FTIR, ¹³C NMR, GC, and HPLC. It was shown that the yield of the amidation reaction is about 80%, and that of the sulfation reaction can exceed 100% against the pure amide (more than one sulfate group could be linked to one amide molecule). On the other hand, the Borghetty test showed that the product is an effective dispersant with a lime soap dispersing power equal to five.     

玉米芯木聚糖硫酸酯的合成、表征及其抗凝血活性

以碱法提取的玉米芯木聚糖为原料,LiCl为催化剂,在非质子溶剂中,采用三氧化硫-吡啶法合成了玉米芯木聚糖硫酸酯（XS）,通过正交试验对合成工艺进行了优化,并采用凝胶渗透色谱（GPC）、红外光谱（FT-IR）、元素分析和¹³C NMR对其结构与性能进行了表征,进一步考察了其体外抗凝血活性。结果表明：在DMF溶剂中,当三氧化硫-吡啶络合物与木糖羟基单元的物质的量之比为1.5：1时,于55℃反应3 h,木聚糖的酯化效果最好,所制备的XS的取代度（D_S）为1.53,得率为78.2%,重均相对分子质量为36 754,分散系数为1.191。结构表征发现,硫酸酯基已经成功引入木聚糖中。体外抗凝血活性结果表明：XS可以延长APTT和TT,具有一定的抗凝血活性;当取代度为1.53、质量浓度为20 mg/L时,XS的APTT、PT和TT分别为36.37、14.22和14.70 s,与阳性对照肝素钠基本相当。     

Acidity of sulfated zirconia as studied by FTIR spectroscopy of adsorbed CO and NH3 as probe molecules

The acid properties of pure and sulfated zirconias were studied by FTIR spectroscopy of adsorbed CO and NH₃ as probe molecules. Whereas pure monoclinic zirconia shows only Lewis acidity, sulfation of tetragonal and monoclinic zirconia creates new bridging OH groups. Two types of Brønsted-acidic centers and two types of Lewis-acidic centers with enhanced acid strength were identified. A communication between the different types of Lewis-acidic sites and the related adsorbed sulfate molecules could be shown. The coordination of basic molecules such as CO onto Lewis-acid sites induces a decrease of the intrinsic Brønsted-acidity of the bridging OH groups. These effects are discussed on the basis of a model of the acidic centers that was previously proposed.On leave from Department of Chemistry, Faculty of Science, Minia University, El-Minia, Egypt.     

抗凝血硫酸化微晶纤维素的制备

以微晶纤维素(MC)为原料,采用氯磺酸-DMF硫酸化方法制备了具有抗凝血活性的硫酸微晶纤维素钠盐Na-MCS,并研究了以提高产物抗凝血活性为目标的工艺,即在常温条件下向原料MC中加入适量的浸润试剂DMF,并在真空下搅拌浸润;在盐水冰浴中制备氯磺酸-DMF酯化试剂;将适量酯化试剂加入已浸润的MC中搅拌反应;调节反应产物的pH值,在去离子水中透析,减压浓缩后真空干燥。     

Free Radical Formation in ZrO2–SiO2Sol–Gel Derived Catalysts

Zirconia–silica mixed oxides have been prepared by the sol–gel method using zirconium butoxide and tetraethoxysilane as starting materials. The samples were sulfated using sulfuric acid as alkoxide hydrolysis catalyst or by impregnation with sulfuric acid of a sample previously prepared using HCl as alkoxide hydrolysis catalyst. In thermally treated samples, an intense EPR signal was observed for the sample prepared using HCl, while the EPR signal was lower in the sulfated samples. FTIR–pyridine adsorption spectra showed that Brønsted and Lewis acidity is developed in the sulfated samples. The formation of two types of Brønsted sites depending upon the sulfating method used is proposed. The catalytic activity of the samples was evaluated in isopropanol andn-butanol dehydration. The mechanism by which sulfation is achieved and the Brønsted-type site formed are discussed.     

细菌纤维素表面硫酸酯化改性及吸湿保湿性能研究

文章以SO3·Py、ClSO3H-DMF为酯化剂,分别在吡啶和DMF中,在室温下对细菌纤维素进行非均相表面改性,得到了取代度0.01-0.14的细菌纤维素硫酸酯（BCS）,采用元素分析、FTIR、SEM对产物进行了结构表征,BCS在1257 cm-1和815 cm-1出现O=S=O和C-O-S的特征吸收峰,BCS表面孔隙率和孔隙大小减小。BC和BCS在RH 43%和RH 81%的相对湿度环境下,具有较好吸湿保湿性能。     

新型丝素复合膜的微结构表征及热稳定性

基于丝素的高分子复合材料可以广泛地应用于组织工程、生物医药和半导体材料等领域。通过物理-共混技术制备了一种新型生物高分子丝素/聚乳酸复合膜。利用扫描电镜、傅里叶红外光谱、拉曼光谱、X射线衍射和热分析技术对其形貌、结构和相态组分以及热稳定性进行了表征，探究了不同比例复合膜的微结构、相互作用机理和热稳定性。结果表明：随着丝素含量的增加，复合膜中的β-折叠含量增多，α-螺旋和无规卷曲含量减少，玻璃化转变温度提高；由于丝素与聚乳酸间的相互作用，提高了复合膜的热稳定性。     

抗凝血硫酸化微晶纤维素钠构效关系的初步研究

采用UV、IR、13CNMR和元素分析对3种由不同制备工艺参数所获得的硫酸化微晶纤维素钠(Na-MCS)进行结构分析,并研究其抗凝血活性。IR、UV揭示Na-MCS结构中含有硫酸酯基;13CNMR表明,3种Na-MCS的硫酸基取代模式相似,即C6取代占主导,C2位部分取代,C3位不发生取代;元素分析测得其硫酸取代度(DS)不同,即DSNa-MCS1=1 70、DSNa-MCS2=1 45、DSNa-MCS3=1 19;抗凝血研究表明,三者均可使血浆中活化部分凝血活酶时间(APTT)和凝血酶时间(TT)延长,但凝血酶原时间(PT)不延长,三者在抗凝血活性大小上存有差异,这与DS有关,在血浆中质量浓度为5μg/mL时,高DS的Na-MCS1使APTT达到155s、TT达34s,而低DS的Na-MCS3使APTT达到85s、TT达18s。构效关系分析表明,DS的差异不改变Na-MCS的抗凝血途径,但影响其抗凝血活性大小,DS越高,抗凝血活性越强。     

NMR and FT Raman characterisation of regioselectively sulfated chitosan regarding the distribution of sulfate groups and the degree of substitution

Chitosan sulfates (CHS) were prepared with chlorosulfonic acid homogeneously and non-homogeneously. The total degrees of substitution (DS) ascribed to sulfate groups (DS_S) were determined with elemental analysis and the partial DS at 6-O-position was estimated via ¹³C NMR. CHS with diverse total DS_S and sulfation patterns were obtained according to the analysis. The effects of selected reaction parameters that can influence the distribution of sulfate groups were examined. The structure of CHS was then characterized with various NMR techniques, i.e. one- (1D-) and two-dimensional (2D-) NMR, and FT Raman spectroscopy. It was found that the primary hydroxyl groups were always predominantly sulfated for CHS prepared under homogeneous or non-homogeneous conditions and no sulfate groups at 2-N-position could be detected. Finally, the feasibility of using FT Raman spectroscopy as another alternative for determining the total DS_S of CHS was presented.     

ISOMERIZATION OF N-BUTANE: CONVERSION AS A FUNCTION OF SULFATE LOADING ON SULFATED ZIRCONIA CATALYSTS

Sulfur loading on a sulfated zirconia catalyst was studied as a function of H 2 SO 4 concentration. The resulting catalytic activity was tested using the isomerization of n -butane as a reaction probe at 200°C. Optimum catalytic activity was observed for a catalyst prepared using 0.5 N H 2 SO 4 . The amount of carbon required to completely deactivate the catalyst was determined using a TGA/FTIR technique. For all of the catalysts synthesized in this study it was found that two active sulfate sites were poisoned by a single deposited carbon atom. Using this information, an active site composed of two coupled sulfate sites, perhaps a surface pyrosulfate site, is suggested. Using a TGA/FTIR technique it was found that the number of catalytically active sulfate sites never exceeded 14% of the total sulfate loading. These results were also supported by calorimetric studies.     

Preparation of hydroxy acids by sulfation of oleic and linoleic acids

Summary Monohydroxystearic acids were prepared by sulfation and subsequent hydrolysis of oleic acid, and the effect of reaction conditions on yield was studied. Monohydroxystearic acids were obtained from commercial oleic acid in 72% yield and from pure oleic acid in 86% yield. Conditions for the best yields apparently gave increased amounts of isomeric hydroxy acids. Hydroxy acids prepared by the sulfation and subsequent hydrolysis of linoleic acid were converted to methyl esters, and purified by fractional distillation and low temperature crystallization. Experimental evidence indicates that sulfuric acid reacts with one double bond of linoleic acid to form isomeric monohydroxyoleic acids and with both double bonds to form dihydroxystearic acids. The by-products formed by the sulfation of linoleic acid include both ester-type polymers and additional polymeric material which cannot be converted to monomers by alkaline saponification. When commercial oleic acid is sulfated and subsequently hydrolyzed, the monohydroxystearic acid thus obtained presumably contains monohydroxyoleic acids and dihydroxystearic acids resulting from the linoleic acid present in the starting material. The formation of an unsaponifiable polymer during the sulfation of linoleic acid accounts in part for the lower yield of hydroxy acids obtained from commercial oleic acid, as compared with that of purified oleic acid. One of the laboratories of the Bureau of Agricultural and Industrial Ohemistry, Agricultural Research Administration, U. S. Department of Agriculture.     

A novel synthesis method for the preparation of aromatic poly(imide benzoxazole) from trimellitic anhydride chloride and bis(o‐aminophenol)

A poly(imide benzoxazole) was prepared directly from trimellitic anhydride chloride and 2,2‐bis(3‐amino‐4‐hydroxyphenyl)hexafluoropropane (BisAPAF) monomers in a two‐step method. In the first step, a poly(hydroxyamide amic acid) precursor was synthesized by the low‐temperature solution polymerization in an organic solvent. Subsequently, thermal cyclodehydration of the poly(hydroxyamide amic acid) precursor at 350°C produced the corresponding poly(imide benzoxazole). The inherent viscosity of the precursor polymer was 0.22 dL/g. The cyclized poly(imide benzoxazole) showed a glass transition temperature (T_g) at 329°C and a 5% weight loss temperature at 530°C in nitrogen and at 525°C in air. The poly(imide benzoxazole) is amorphous as evidenced by the wide‐angle X‐ray diffraction measurement. The structures of the precursor polymer and the fully cyclized polymer were characterized by Fourier transform infrared (FTIR) and proton nuclear magnetic resonance spectroscopy (¹H NMR). © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2388–2391, 2003     

介孔SO_4~(2-)/ZrO_2的制备、表征及性能

以正丙醇锆为锆前躯体,硫酸铵为硫源,十六烷基三甲基溴化铵(CTAB)为模板剂,溴化钾为添加剂,按n(Zr4+)∶n(CTAB)∶n(SO24-)=2∶1∶2,在水热条件、酸性介质中合成了介孔ZrO2/SO24-。通过X射线衍射(XRD),N2物理吸附,扫描电镜(SEM),FTIR分析手段对其结构进行了表征;并以乙酸正丁酯的酯化反应为探针反应,考察了其催化活性。结果表明,采用两步焙烧法去除模板剂后,该样品的介孔结构类似于MCM-41,d值为3.85nm;在500℃焙烧后,该样品仍具有274m2/g的比表面积及3.2nm的平均孔径;SEM显示焙烧后的样品形貌为球形颗粒;FTIR分析得出,焙烧产物ZrO2/SO42-中S=O键对Zr4+有强的吸电子作用,产生强的Lewis酸中心。当催化剂用量为正丁醇质量的2.5%,n(乙酸)∶n(正丁醇)=1∶2,反应3h后,乙酸的转化率达91.48%。     

丝素蛋白/聚丙烯酸共混膜仿生合成羟基磷灰石

将丝素蛋白(SF)与聚丙烯酸(PAA)共混,制备丝素蛋白/聚丙烯酸(SF/PAA)共混膜;然后将此共混膜进行改性及矿化处理后,放置于(37±0.5)℃人体仿生液中24h,诱导合成丝素蛋白/羟基磷灰石(SF/HA)复合材料.利用傅里叶红外(FTIR)、X-射线衍射(XRD)、环境扫描电镜(ESEM)以及X射线能谱(EDX...     

Isomerization of n-butane: Conversion as a function of sulfate loading on sulfated zirconia catalysts

Sulfur loading on a sulfated zirconia catalyst was studied as a function of H 2 SO 4 concentration. The resulting catalytic activity was tested using the isomerization of n -butane as a reaction probe at 200°C. Optimum catalytic activity was observed for a catalyst prepared using 0.5 N H 2 SO 4 . The amount of carbon required to completely deactivate the catalyst was determined using a TGA/FTIR technique. For all of the catalysts synthesized in this study it was found that two active sulfate sites were poisoned by a single deposited carbon atom. Using this information, an active site composed of two coupled sulfate sites, perhaps a surface pyrosulfate site, is suggested. Using a TGA/FTIR technique it was found that the number of catalytically active sulfate sites never exceeded 14% of the total sulfate loading. These results were also supported by calorimetric studies.     

Thermal rearrangement of sulfated tallow alkanolamides

A study of reaction variables in the sulfation of tallow alkanolamides revealed that a molecular rearrangement to aminoester occurs as a result of prolonged heating in the unneutralized state. Heating sulfated isopropanolamide for 4 hr at 60 C resulted in a 60% loss of active ingredient. The sulfated diglycolamide heated at 60 C for 12 hr suffered a loss of 22% active ingredient. A 50:50 mixture of these sulfated alkanolamides heated for 12 hr at 40 C incurred no loss of active ingredient content, whereas at 60 C a 40% loss of active ingredient was observed. Thus, careful temperature control and rapid neutralization after sulfation are required to obtain sulfated alkanolamides with a high percentage of active ingredient. Agricultural Research, Science and Education Administration, USDA.     

丝素膜上接枝褐藻多糖硫酸酯及其体外抗凝血性能的研究

以戊二醛为交联剂,将褐藻多糖硫酸酯接枝在NH3等离子体处理的丝素膜的表面上。主要探讨了pH、反应温度、反应时间对丝素膜接枝效果的影响。用XPS分析了丝素膜表面化学元素。采用部分凝血活酶时间(APTT)、凝血活酶时间(PT)、凝血酶时间(TT)评价了接枝膜的体外抗凝血活性。得出最佳接枝工艺为:pH=2,反应温度40℃,反应时间6h。在该工艺条件下,接枝丝素膜APTT的最佳值为72s,APTT、TT凝血时间比空白对照分别延长37s和6s以上,具有抗凝血性能。经稳定性测试,固定的褐藻多糖硫酸酯基本上不脱落,从而获得了一种具有抗凝血性的新颖生物材料。     

Synthetic detergents from animal fats. IV. Sodium 9,10-dichlorooctadecyl sulfates

Summary Sodium 9,10-dichlorooctadecyl sulfates were prepared by the addition of chlorine to oleyl and to elaidyl alcohols, and sulfation of the dichlorooctadecanols with chlorosulfonic acid. The sodium 9,10-dichlorooctadecyl sulfates are readily soluble in water at 25°C and resemble sodium oleyl sulfate in detergent and surface-active properties. Tallow alcohols can be chlorinated by the addition of chlorine and sulfated with one of the usual sulfating agents to produce an adequately soluble detergent and surface-active agent. I, II, and III in this series are references (5), (4), and (7), respectively. Presented at the meeting of the American Oil Chemists' Society in Minneapolis, October 1954. A laboratory of the Eastern Utilization Research Branch, Agricultural Research Service, U. S. Department of Agriculture.     

Methyl methacrylate and acrylamide crosslinked macroporous copolymers

In this work the synthesis of a crosslinked macroporous copolymer was effected from methyl methacrylate and acrylamide. The synthesis process began with emulsion prepolymerization, followed by sol–gel copolymerization until a hard block was obtained. Determination of the properties of the obtained material was carried out by FTIR, mercury porosimetry, and SEM microscopy. The material was characterized by a porous structure with open pores. The macroporous copolymer obtained can be used for polymer–analog reactions and the transformation of amide and ester groups into acyl azide groups. It can be used as a hard inert support for the immobilization of enzymes, or other proteins, by condensation of acyl azide group on polymer with the free amino group from the base amino acid of enzyme/protein. For the immobilization of microorganisms it can be used by vacuum diffusion of microorganism suspension into the porous structure, without active group transformation reactions. With microorganisms in the polymer pores, microorganism colonies form within the copolymer by microbial fermentation. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 387–395, 2004