1,1'-(六甲基三硅撑)双环戊二烯基二(对氯苯氧基)钛的合成及晶体结构

以1,3-二氯六甲基三硅烷相继与环戊二烯基钠、正丁基锂和四氯化钛作用合成了1,1'-(六甲基三硅撑)双环戊二烯基二氯化钛(1),1在氨基钠的存在下与对氯苯酚作用制得题目化合物(2)。通过元素分析、^1HNMR和MS鉴定了1与2的结构,并对2进行X射线结构分析确证了其结构。2的晶体属单斜晶系的P21/c空间群。晶胞参数:a=1.0746(3),b=2.4865(7),c=1.2568(2)nm; β=113.42(2)°;V=3.08137nm^3;Z=4,D0=1.305g·cm^-3。化合物中三个硅原子的桥链发生明显扭曲。通过氧原子中心原钛与苯环发生共轭,使整个分子形成共轭体系。     

甲氧基代多个氧化乙烯结构交联型酚醛聚合物的合成

采用对甲氧基苯酚、多缩乙二醇二氯化物为原料, 合成了五个4,4'-二甲氧基多缩乙二醇二苯醚新单体; 分别经甲醛、2,6-二羟甲基对甲氧基苯酚聚合, 得到二个系列甲氧基代多个氧化乙烯结构交联型酚醛聚合物。这些聚合物含有假冠醚结构单元, 配合容量在0.9-3.0mmol/g之间, 可作为配合树脂使用, 富集分离多种金属离子。     

2-(N-三氟乙酰-N-三甲基硅烷基)氨基-3-三甲基硅烷氧基-羧酸三甲基硅烷酯和2-(N-三氟乙酰)-2,3-脱氢氨基酸的合成

利用三氟甲基磺酸三甲基硅烷酯, 我们合成了一种新的、化学活性很高的合成中间产物2-(N-三氟乙酰-N-三甲基硅烷基)氨基-1, 1-二(三甲基硅烷氧基)乙烯。脂肪醛或芳香醛发生碳碳成键的加成反应, 生成β碳原子上带有易离去基团三甲基硅烷氧基、N原子上带有保护基团三氟乙酰基的α氨基酸三甲基硅烷酯。消除反应得到了一个合成α、β脱氢氨基酸的可行途径。这类化合物是合成复杂多肽和肽生物碱的基元物。     

LOW DENSITY POLYETHYLENE/CLAY NANOCOMPOSITES MODIFIED BY ETHYLENE COPOLYMERS： EFFECTS OF FUNCTIONALIZED SEGMENTS ON MORPHOLOGY

Melt extrusion was used to prepare binary nanocomposites of ethylene copolymers and organoclay and trinary nanocomposites of low-density polyethylene （LDPE）, ethylene copolymer and organoclay. X-ray diffraction （XRD） and transmission electron microscopy （TEM） were used to analyze the structure of the clay phase and the morphology of the nanocomposites. Influences of the comonomer in the copolymer and the content of the copolymer on the morphology of the resulting nanocomposites were discussed. The binary and the trinary composites may form intercalated or exfoliated structures depending on the interaction between the copolymer and the clay layers and the content of the copolymer.     

聚-4-氧杂0-6，7-二甲硒基庚基硅氧烷钯（0）配合物的合成及其催化性能研究

4-氧杂-6，7-二氯庚基三甲氧基硅烷依次与气相法二氧化硅、甲硒基钠、氯化 钯作用，然后用水合肼还原，合成了二氧化硅负载的聚-4-氧杂，6，7-二甲硒基庚 基硅氧烷钯(O)配合物．该配合物是苯乙烯及丙烯酸的Heck芳基化反应的有效催化 剂，为立体选择性地合成各种取代的反式-1，2-二苯乙烯及反式肉桂酸提供了简便 且实用的新方法     

Multiscale Reinforcement of Polymers Combining Cellulosic Wood Pulp with Layered Silicate Nanoplatelets

Synergies resulting from the combination of discontinuous reinforcing elements at two different size scales are examined in two polymer types — rubbery matrices comprising acrylonitrile-co-butadiene (NBR) elastomer and a high density polyethylene plastic. The latter is derived from a recycled post-consumer waste stream that is upgraded by the reinforcement to compensate for any degradation experienced during prior use or impurities introduced during recycling. The two reinforcements are wood pulp at the microscale and exfoliating layered silicate clays at the nanoscale. Appropriate compatibilizing agents are employed to allow wetting of the reinforcement with the polymer matrix, promote dispersion and provide a strong interface. In general, the microscale elements provide mechanical strengthening in tension, while the nanoscale reinforcements enhance stiffening and reduce failure propagation by tearing. The use of natural reinforcements and recycled feedstocks imparts environmental acceptability to such formulations.     

A NOVEL ZWITTERIONIC SILANE COUPLING AGENT FOR NONTHROMBOGENIC BIOMATERIALS

A novel silane coupling agent bearing sulfobetaine group, N,N-diethyl-N-（3-sulfopropyl）-aminopropyl- trimethoxysilane （DESATS）, was first designed, synthesized and characterized. Its solution property was studied by means of dynamic light scattering. DESATS was successfully bonded onto the surface of the glass and proved by ESCA. Platelet adhesion assay in vitro indicated that the nonthrombogenicity of glass slide modified with DESATS is greatly improved.     

Acceleration of silanol condensation of a methacryl-functional silane in the model sizing system

The silanol condensation of hydrolyzed γ-methacryloxypropyltrimethoxysilane (γ-MPS) in the presence of a typical film-forming polymer, poly(vinyl acetate), PVAc, has been studied. The model sizing system, consisting of the hydrolyzates of γ-MPS and PVAc obtained from the alcoholic aqueous solution, is studied using Fourier transform infrared spectroscopy (FT-IR) and size exclusion chromatography (SEC). In the initial stage of silanol condensation of the hydrolyzates of the model sizing system, it has been found that the condensation reaction is accelerated compared with the system that contains no film-former. It has also been found that the structure of γ-MPS oligomer is relatively ordered and less-active for further silanol condensation. The least-square curve-fitting procedure for FT-IR spectra indicates five carbonyl stretching bands, reflecting the hydrogen bonded and the free carbonyl groups of the silane coupling agent and the film-forming polymer.     

Interfacial Properties of Phosphate Glass Fiber/Poly(caprolactone) System Measured Using the Single Fiber Fragmentation Test

Phosphate glass fiber of the composition 20Na₂O–24MgO–16CaO–40P₂O₅ was produced using an in-house fiber drawing rig. The interfacial properties of the phosphate glass fiber/poly(caprolactone) (PCL) system were measured using the single fiber fragmentation test (SFFT). The system was calibrated using E-glass fibers and polypropylene system. This gave an interfacial shear strength (IFSS) of 4.1 MPa, which agrees well with other published data. The IFSS for the unsized (as drawn) phosphate glass fiber/PCL system was found to be 1.75 MPa. Fibers treated with 3-aminopropyl-triethoxy silane (APS) showed an IFSS of 3.82 MPa. X-ray photoelectron spectroscopic (XPS) analysis of unsized and silane sized fibers established the presence of silane on the fiber surface. Degradation tests of the silane treated fiber/PCL samples were carried out in deionised water at 37°C and it was found that the IFSS values decreased over time. Four others silanes were also investigated but APS gave the highest IFSS values.