Surface and Thermodynamic Properties of Nonionic Surfactants Based on Rosin-Maleic Anhydride and Acrylic Acid Adducts

Ester-adduct derivatives of rosin were synthesized by reacting rosin maleic anhydride (RMA) or rosin acrylic acid (RAA) adducts with polyethylene glycol 600 (PEG600), 1000 (PEG1000) or 2000 (PEG2000) and at elevated temperature. These derivatives were evaluated for acid number, FTIR spectroscopy, molecular weight (Mw) and polydispersity. The surface properties of the prepared surfactants were determined by measuring the surface tension at different temperatures. The surface tension, critical micelle concentration, and surface activities were determined at different temperatures. Surface parameters such as surface excess concentration (Γmax), the area per molecule at interface (Amin) and the effectiveness of surface tension reduction (πCMC) were determined from the adsorption isotherms of the prepared surfactants. Some thermodynamic data for the adsorption process were calculated and are discussed.     

Synthesis and Properties of Nonionic Surfactants from Rosin-Imides Maleic Anhydride Adduct

Ester-adduct derivatives of rosin were synthesized by reacting rosin with polyethylene glycol 600 (PEG 600) or 2000 (PEG2000) and maleic anhydride (MA) at elevated temperature. These derivatives were evaluated for acid number, FTIR spectroscopy, molecular weight (Mw), and polydispersity. The derivatives were soluble in organic solvents; aqueous solubility was pH dependent. Rosin-imides were synthesized from a rosin ester-maleic anhydride adducts. It was condensed with diaminobutane or triethylene tetramine to obtain rosinimides. This imide was etherified by reaction with PEG in the presence of β,β′-dichlorodiethyl ether as a linking agent and NaOH as a catalyst. The surface properties of the prepared surfactants were determined by measuring the surface tension at different temperatures. The surface tension, critical micelle concentration and surface activities were determined at different temperatures. Surface parameters such as surface excess concentration (Γmax), the area per molecule at interface (Amin), and the effectiveness of surface tension reduction (πCMC) were determined from the adsorption isotherms of the prepared surfactants. Some thermodynamic data for the adsorption process were calculated and are discussed.     

Synthesis and Evaluation of Ethoxylated Alkyl Sulfosuccinates as Oil Spill Dispersants

The surface properties particularly, Krafft point, foam stability and emulsion stability for the synthesized series of ethoxylated sodium monoalkyl (octyl-, dodecyl-, and cetyl-) sulfosuccinate surfactants were investigated comparing with those of sodium dioctyl sulfosuccinate. The prepared surfactants were evaluated as oil spill dispersants using screen test method. The results show that, the ethylene oxide units in the mixed moiety surfactant system (anionic–nonionic) effect on the depression of the Krafft point. Also, the increasing of ethylene oxide units in the prepared surfactants decreases the foam ability of these surfactants. The results of emulsion stability show that, the increasing in ethylene oxide units owing to the emulsion stability decreases. The prepared surfactants show a dispersion capability at different content of ethylene oxide units (9, 14, 23, and 90) and at different concentrations. The dispersion capability for these surfactants in the sea water is better than in the fresh water. The results show that, the increase of ethylene oxide units increases the dispersion efficiency of the synthesized surfactants.     

Adhesives Based on Formaldehyde Condensation Resins

Formaldehyde based resins are by far the most important adhesives for the production of wood based panels. This paper reviews in compact form the main application near features of these products including their composition, their molar mass distribution as well as their hardening behaviour, which all three parameters have decisive influence on the properties of the resins themselves and their performance as wood adhesives.     

以马来松香丙烯酸乙二醇酯为交联剂的咖啡因分子印迹电化学传感器

以咖啡因为模板分子, 含菲环骨架的马来松香丙烯酸乙二醇酯为交联剂, 甲基丙烯酸为功能单体, 在玻碳电极表面以自由基热聚合的方式制备分子印迹聚合物敏感膜, 构建了测定咖啡因的新型分子印迹膜电化学传感器. 通过循环伏安法、 差分脉冲伏安法及电化学交流阻抗法研究了传感器对咖啡因的响应特性. 结果表明, 在最佳的实验条件下, 传感器的峰电流与咖啡因浓度在3.00×10^-3~2.73 mmol/L范围内呈现良好的线性关系, 检出限(S/N=3)为1.12×10^-4 mmol/L. 传感器具有良好的选择性和重现性. 将该传感器用于可口可乐饮料中咖啡因含量的测定, 平均回收率为98.7%.     

Micellization and Adsorption Parameters of Poly(Propylene Oxide)/Poly(Ethylene Glycol) Block and Graft Copolymers in Aqueous Medium

This work aims to measure the adsorption and micellization parameters of new water soluble nonionic amphiphilic block and graft copolymers based on hydrophilic poly (ethylene glycol) (PEG) and hydrophobic poly (propylene oxide) (PPO) at ambient temperature and normal atmospheric pressure. The chemical composition and molecular weights of the prepared copolymers were determined from ¹H NMR analyses. The surface properties of the prepared surfactants were determined by measuring the surface tension at different temperatures. The surface tension, critical micelle concentration, and surface activities were determined at different temperatures. Surface parameters such as surface excess concentration, the area per molecule at interface and the effectiveness of surface tension reduction were determined from the adsorption isotherms of the prepared surfactants. Some thermodynamic data for the adsorption and micellization process were calculated and are discussed.     

Synthesis of Some Oil Spill Dispersants Based on Sorbitol Esters and Their Capability to Disperse Crude Oil on Seawater to Alleviate Its Accumulation and Environmental Impact

In this respect mono‐, di‐, and tri‐ sorbitol oleate esters [SMO, SDO, and STO] were prepared and then ethoxylated using ethylene oxide to obtain six sorbitol esters at different ethylene oxide content (e.o=5, 12, 15, 20, 35, and 45). They were tested as oil spill dispersants individually and in blends. From the obtained data, it was found that the blends are more effective than the corresponding individual surfactants. The maximum dispersion capability for the prepared surfactants was obtained at HLB range from 9 to 11 for the both individual surfactants and blends. The increase of total carbon number in the surfactant alkyl group leads to increase dispersion capability of the dispersant. The wide range of ethylene oxide content was used, but the maximum dispersion efficiency was obtained at ethylene oxide=20 in E(20)STO. Meanwhile, the dispersion capability increases when the interfacial tension decreases.     

Synthesis of Oil Spill Sorbents Based on Cellulose Derivatives

In this work, hydroxypropyl cellulose (HPC) was used to synthesize hydroxypropylcellulose acrylate (HPCA) macromonomer by esterification of HPC with acryloyl chloride in homogenous solution of DMF. Then the produced HPCA monomer was copolymerized with ethylhexyl acrylate (EHA) in presence of two types of crosslinkers to produce oil gel. Several parameters were considered, namely, monomers feed ratio, type and concentration of the applied crosslinkers. The chemical structures of both HPC and HPCA were confirmed by using FTIR and ¹H NMR spectroscopic analyses. Also, the thermal properties of the crosslinked oil absorbents were investigated by using TGA. Furthermore, morphological propoeries of these crosslinked sorbers were studied through SEM and their swelling efficiency was thoroughly investigated in heavy and light oil.     

含松香骨架的新型手性季铵盐相转移催化剂的合成及其在不对称环氧化反应中的应用

以天然松香为原料合成了4个新型手性季铵盐类相转移催化剂, 并用于催化不对称查尔酮环氧化反应, 发现这类手性相转移催化剂可以有效地催化查尔酮的不对称环氧化, 环氧化产物ee最高达20%.     

Application of New Modified Poly(ethylene Oxide)-Block-Poly(propylene oxide)-Block-Poly(ethylene oxide) Copolymers as Demulsifier for Petroleum Crude Oil Emulsion

Water soluble nonionic amphiphilic block copolymers based on hydrophilic poly(ethylene glycol) (PEG) and hydrophobic poly(propylene glycol) (PPG) were prepared. Poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) copolymers, PEG-PPG-PEG, were prepared in the normal condition. The chemical composition and molecular weights of the prepared copolymers were determined from ¹H NMR and GPC techniques. The surface properties of the prepared surfactants were determined by measuring the surface tension at different temperatures. The prepared nonionic surfactants were evaluated as demulsifiers for water in crude-oil emulsions that were pronounced at different ratios of crude oil: water at 318 K and 333 K. The experimental results showed that the dehydration rate of the prepared demulsifiers reached 100% based on demulsifier chemical compositions and concentrations.     

Development and Characterization of an Electrochemical Sensor for Cinchonidine Detection Based on Molecularly Imprinted Polymer with Modified Rosin as Cross-linker

Molecularly imprinted polymers(MIPs) were applied as molecular recognition elements to an electrochemical sensor for cinchonidine(CD). A kind of MIP was synthesized with cinchonidine as template, modified rosin( ethylene glycol maleic rosinate acrylate) containing the skeleton of phenanthrene rings as cross-linker and methylacrylic acid as functional monomer. MIP membrane was prepared on a glassy carbon electrode for the determination of CD via free radical polymerization method. Electrochemical impedance spectroscopy(EIS) and cyclic voltammetry( CV) were used to characterize the membrane electrochemical behavior in electrode fabrication process. The experimental conditions were discussed. Under optimum conditions, it was found that the response of peak currents was linear to the concentration of CD in a range of 0.013―2.26 mmol/L. The detection limit for CD is 1 μmol/L, the relative standard deviation for 100 μmol/L CD is 1.34% and the incubation time is 2 min. The sensor was applied to the determination of CD in urine samples with satisfactory results.     

Innovative Cross-Linked Polyurethane Networks Based on Cyclodextrins and Polyethylene Glycols: Inclusion Capacity and Potential Use as Controlled Release Carrier for Nifedipine

Summary: Polymers derived from cyclodextrins show several biomedical applications. In this paper, six cross-linked polyurethane networks based on β-cyclodextrin (βCD) or hydroxypropyl-β-cyclodextrin (HPβCD) and polyethylene glycols (PEG 400, PEG 1500 or PEG 4000) were synthesized by the usual two-step polymerization method. The polymers were characterized by Fourier-transformed infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and X-ray diffraction (XRD). The inclusion capacity was evaluated by the discoloration method of a phenolphthalein solution. In order to explore their potential use as controlled drug delivery systems, dissolution profiles and release behavior of inclusion complexes between PUR/TDI/βCD/PEG4000 or PUR/TDI/HPβCD/PEG1500 and nifedipine (NIF) were investigated. FTIR assignments confirmed the formation of urethane linkages. XRD patterns revealed that the crystallinity decreased mainly due to the crosslinking process. TGA showed three stages of mass loss attributed to water loss, cleavage of urethane bonds and volatilization of decomposition products. The inclusion capacity of cyclodextrins cross-linked with polyurethane was suitably maintained. Dissolution profiles demonstrated that the inclusion complexes PUR/TDI/βCD/PEG4000-NIF and PUR/TDI/HPβCD/PEG1500-NIF are feasible systems for controlling drug release, showing a biexponential release behavior.     

基于主成分和支持向量机浓度参量同步荧光光谱油种鉴别

基于浓度参量同步荧光光谱技术,对不同溢油类型不同油源原油样品集、引入外扰相似油源样品集进行光谱数据采集,获取其浓度同步荧光光谱矩阵Concentration-Synchronous-Matrix-Fluorescence(CSMF),利用主成分分析方法对两套不同层次的原油相关样品集进行了多类分类识别。结果表明:主成分载荷图可以很好地反映各个原油相关样品在油源上的相似程度,结合支持向量机可以实现不同溢油类型及不同油源原油的准确分类,对于引入风化和海水外扰相似油源溢油样品集,两类分类区分的结果远远高于多类分类识别的结果。通过详细的主成分分析讨论,为溢油油种鉴别提供了一种利用多类分类识别,逐步缩减嫌疑样本数量,最后通过两两分类实现溢油样品准确识别的新思路。     

六羟基化合物为骨架的高分子固-固相变材料的合成与性能

分别使用三种含6个羟基的化合物(山梨醇、双季戊四醇和肌醇)作为分子骨架,聚乙二醇(PEG)作为相变功能链,4,4'-二苯基甲烷二异氰酸酯(MDI)为交联剂,合成了3种具有不同交联结构的新型固-固相变储能材料。通过傅里叶变换红外光谱(FT IR)、X-射线衍射(XRD)、偏光显微镜(POM)、示差扫描量热法(DSC)和热重量分析法(TG)分别对合成材料的分子结构、结晶性能、相变行为和热稳定性进行了研究。结果显示,所制备的材料在30~70℃温度范围内具有典型的固-固相变特性,其升温和冷却过程的相变焓最高可达107.5J/g和102.9J/g。此外,通过热重分析发现所合成材料具有较好的可重复使用性和热稳定性。因此,合成的新型固-固相变材料在热能储存和控温领域具有巨大的应用潜力。     

Synthesis of Some Additives and Study Effect of Gas Oil Composition on Flow Properties

Nine additives were prepared by esterification of dibasic acid (succinic, adipic, sebacic acid) and polyethylene glycol (Mol.wt.=600, 1000, 4000). These additives were characterized by infrared spectral analysis, average molecular weight and polydispersity index. Their influence on the depression of pour point for two type of paraffin gas oils (G1 and G2) were investigated, blends of paraffin gas oils G1 and G2 by different ratio, when their untreated and treated by additives were evaluated as pour point depressant in comparison with the original paraffin gas oils G1 and G2.

The effect of additive type and gas oil composition on wax crystal modification were studied using the photo micrographic analysis. Diethoxylate (eo=182) sebacate with blend gas oil No. 3 has achieved the best performance as pour point depressant. The photo micrographic analysis showed that, the wax morphology was greatly modified to fine dispersed crystals of compact size. A correlation between the pour point depression and the extent of wax modification was detected.     

基于聚琥珀酰亚胺衍生物仿生超亲水表面的制备及性能

利用对聚琥珀酰亚胺(PSI)的亲核加成反应,仿生设计合成侧基带有多巴胺和磺酸甜菜碱两性离子基团的新型聚琥珀酰亚胺衍生物(PSI-DA-ZW);通过聚琥珀酰亚胺衍生物中多巴邻苯二酚基团的氧化自聚和沉积,制备了仿生超亲水功能涂层表面(PSI-DA-ZW/glass).利用X射线光电子能谱仪(XPS)、扫描电子显微镜(SEM...     

基于骨组织工程的静电纺纳米纤维

通过模仿天然骨的成分、结构特性对材料进行设计与调控,获得新型仿生人工骨修复材料,这已成为骨修复材料发展的主要趋势之一。静电纺纳米纤维具有可调控的纳米结构、高孔隙率和大比表面积,可以模拟天然细胞外基质的结构和生物功能,被广泛应用于骨组织工程。本文提供一个基于骨组织工程的静电纺纳米纤维的全面概述。首先简要介绍了骨组织工程,并讨论了静电纺原理、参数和典型设备。随后,讨论了静电纺纳米纤维的表面改性方法,并通过关注最具代表性的实例重点介绍了与静电纺纳米纤维和静电纺纳米纤维增强复合材料的应用最相关的最新进展。此外,本综述展望了静电纺纳米纤维未来发展的挑战、机遇以及新方向。     

Promising Antidiabetic and Antimicrobial Agents Based on Fused Pyrimidine Derivatives: Molecular Modeling and Biological Evaluation with Histopathological Effect

Diabetes is the most common metabolic disorder in both developing and non-developing countries, and a well-recognized global health problem. The WHO anticipates an increase in cases from 171 million in 2000 to 366 million by 2030. In the present study, we focus on the preparation of pyrimidine derivatives as potential antidiabetic and antimicrobial agents. Thein vivoeffect on total serum glucose concentration, cholesterol and antioxidant activity was assessed in adult male albino Wister rats and compared to the reference drug glimperide. Promising results were observed for compound 5. The histopathological study confirms that compound 5 results in significant activity with liver maintenance. The antimicrobial activities were evaluated against several bacterial strains such as Salmonella typhimurium ATCC 25566, Bacillus cereus, Escherichia coli NRRN 3008, Pseudomonas aeruginosa ATCC 10145, Staphylococcus aureus ATCC 6538and fungi such as Rhizopus oligosporus, Mucor miehei and Asperillus niger. Compounds 4 and 5 showed a good inhibition of the bacterial zone compared to the reference drug cephradine. Finally, we suggest protein targets for these drugs based on computational analysis, and infer their activities from their predicted modes of binding using molecular modeling. The molecular modeling for compounds 4 and 5 resulted in improved docking scores and hydrogen bonding. The docking studies are in good agreement with the in vitro and in vivo studies.     

基于海藻酸钠衍生物的肝靶向纳米前药的构建及抗肿瘤活性研究

利用寡聚乙二醇(mOEG)修饰海藻酸钠(ALG), 有效降低了ALG的黏度, 提高了其对疏水性肝靶向配体甘草次酸(GA)的负载量. 结果表明, 靶向材料(GA-ALG-mOEG)的GA负载量为11.8%, 是对照组(GA-ALG)的1.97倍. 在此基础上, 以物理交联的方式引入pH响应的阿霉素前药(DOX-ALG-mOEG), 制备了肝靶向纳米前药(DOX-ALG-mOEG/GA-ALG-mOEG NPs). 细胞实验及抑瘤实验结果表明, 该前药较对照组(DOX-ALG/GA-ALG NPs)具有更高的肝靶向性和药物利用率, 其对肝癌细胞的半致死率浓度(IC₅₀)为58.1 ng/mL, 是对照组(IC₅₀=141.7 ng/mL)的41%; 动物实验结果显示, 该前药的抑瘤率达到了88.4%, 比对照组提高了11.5%.