化学气相沉积聚合制备羧基取代聚对亚苯基二亚甲基及其性能研究

用化学气相沉积(CVD)聚合法制备了羧基取代聚对亚苯基二亚甲基(PPX-carb)膜,采用FTIR和元素分析的方法证实了其化学结构.对膜溶解性和抗化学氧化性能的研究表明PPX-carb膜仍具有优异的耐溶剂性和抗化学氧化性能.对PPX-carb膜热性能的研究表明羧基的引入使得膜的玻璃化转变温度降低,室温柔性增强,动态力学阻尼性能增大,与聚对亚苯基二亚甲基(PPX)相比引入了羧基的PPX-carb热稳定性有所下降,热降解起始温度比PPX低,但主链降解温度比PPX反而高出约80℃.此外,羧基的引入使得膜的亲水性能大幅度提高,水汽渗透性能也有所提高.     

碳纳米管的羟甲基化及其马来酸酐接枝研究

利用甲醛的亲电性能, 对化学气相沉积法(CVD)制备的多壁碳纳米管(MWCNTs)进行羟甲基化, 并在此基础上酯化接枝马来酸酐, 运用透射电子显微镜(TEM)、红外光谱和Zeta电位仪表征了改性后的MWCNTs的表面结构. TEM结果显示, 酯化后的MWCNTs明显增粗, 说明表面已附有物质. 红外结果表明, 羟甲基后的MWCNTs的表面有了羟基和亚甲基, 而马来酸酐酯化接枝后的MWCNTs有亚甲基和酯基官能团. 光学图像分析表明, 经甲醛处理后的MWCNTs在水溶液中的分散性明显提高, 而马来酸酐酯化接枝后的MWCNTs在二甲苯中的分散性明显增强. Zeta电位的测试结果表明, 甲醛处理过的MWCNTs颗粒在水中, 负电荷增多, 增强了其在悬浮液在溶液中的稳定性.     

取代甲基亚磺酰基苯并咪唑类化合物的合成

合成了一系列取代甲基硫代苯并咪唑类化合物，并在过氧乙酸的氧化下得到了 取代甲基亚磺酰基苯并咪唑类化合物，收率较好(79%～97%)，代替了用间氯过氧苯 甲酸进行氧化，反应过程稳定，降低了成本。     

苯乙烯马来酸酐共聚物化学改性研究进展

苯乙烯-马来酸酐共聚物具有优异的乳化、成膜、增稠等特性,是一种重要的功能化聚合物.从酯化、胺化、苯环接枝、带上电荷、引入功能性基团和引入第三单体等方面对于苯乙烯-马来酸酐共聚物化学改性进行了全面的总结,简评了各种化学改性的方法及改性共聚物的优点,报道了化学改性方法近年来出现的新进展.     

葡聚糖双亲性衍生物修饰PLA亚微粒子的制备及其表面多重生物因子功能化

以胆固醇半琥珀酸酰氯对NaIO4氧化的醛化葡聚糖进行疏水改性,制备了醛基化双亲性葡聚糖衍生物Chol-Dex-CHO;利用醛基与己二酰肼酰腙化反应,实现葡聚糖主链的氨基化;生物素经二环已基碳二亚胺活化后与双亲性葡聚糖衍生物主链上的氨基偶联,形成生物素化(3%)双亲性葡聚糖(Chol-Dex-Biotin).将聚乳酸(PLA)与Chol-Dex-Biotin溶液共透析可形成亚微粒子,双亲性多糖可通过疏水基团锚定于PLA亚微粒子表面,透射电子显微镜与原子力显微镜测试观察到清晰的球形核壳结构,激光粒度仪测定亚微粒子粒径与粒径分布表明调节Chol-Dex-Biotin与PLA的配比可以控制亚微粒子的粒径(150~200 nm),X-射线光电子能谱证明亚微粒表面存在Chol-Dex-Biotin.在此基础上,以FITC标记的转铁蛋白(Tf-FITC)和生物素化兔IgG为模型生物功能因子,分别通过共价偶联及生物素-亲合素物理结合两种机理对葡聚糖包覆的PLA纳米微粒表面进行多重生物因子功能化修饰,得到表面Tf和IgG双重修饰的PLA亚微粒子(Tf-PLA-IgG submicron particles).亚微粒子表面Tf和兔IgG的结合分别通过荧光显微镜观测和抗IgG-辣根过氧化氢酶(IgG-HRP)显色反应验证.     

铑催化定位基促进芳环C—H键和碳酸亚乙烯酯的缩合得到异香豆素（英文）

异香豆素是一种重要的药物分子,目前已经开发了许多合成途径,主要集中在苯甲酸或其他物质与炔烃的环化.亚磺酰基苯甲酰胺在螯合辅助的芳烃邻位C—H官能化中可以轻松地制备,碳酸亚乙烯酯可以建立无氧化剂的催化体系,使碳酸作为唯一的副产物.在铑催化剂的存在下,亚磺酰基苯甲酰胺和碳酸亚乙烯酯之间形成了环化,通过导向基团辅助的邻位C—H偶联和分子内醇解,以中等至良好的产率获得未取代的异香豆素.     

改性焦粉对亚甲基蓝吸附性能及机理的研究

以废弃焦粉为原料,50%硝酸为改性剂,借助JSM、XPS分析测试方法表征其结构。考察了改性焦粉、焦粉对亚甲基蓝吸附性能、吸附平衡等温线、黏附几率和活化能,用Weber-Morris曲线研究吸附机理。结果表明,硝酸改性焦粉是硝酸刻蚀焦粉表面增加孔结构,增大表面积,表面氧化形成较为丰富含氧功能组的过程;改性焦粉对亚甲基蓝吸附性能明显优于焦粉;改性焦粉吸附量随亚甲基蓝溶液浓度、pH的增大而增加;吸附过程符合Langmuir、Freundlich吸附等温式;黏附几率和活化能分别为S=0.1977、2.5635kJ/mol;该吸附过程主要为颗粒内扩散控制的物理吸附。     

化学气相沉积法制备Ti/HMS催化剂及甲基接枝改性

用化学气相沉积法制备了Ti/HMS介孔分子筛催化剂, 并对其进行甲基接枝改性. 用XRD、N2-吸附、ICP-AES、FTIR, UV-vis和29Si CP/MAS NMR等手段对样品进行了表征, 考察了催化剂的丙烯环氧化性能. 结果表明: 气相沉积法载钛和接枝改性减小了HMS分子筛表面的孔径和比表面, 但是分子筛的介孔特征仍然保持; 随着沉积时间的增加(0.5～2 h), 催化剂的钛含量逐渐增加, 催化活性也随之增加, 但当沉积时间超过2 h后, 钛含量和催化活性均保持不变; 接枝改性后催化剂的环氧化活性和选择性均显著提高; 气相沉积法合成Ti/HMS比水热法合成Ti-HMS具有更高的环氧化催化活性.     

苯乙烯/马来酸酐共聚物修饰碳纳米管的研究

利用羟基碳纳米管上的羟基与马来酸酐之间的简单反应, 在碳纳米管上引入双键, 进一步引发苯乙烯聚合, 在碳纳米管表面接枝苯乙烯马来酸酐共聚物, 同时采用羟基碳纳米管与苯乙烯马来酸酐共聚物直接反应也在碳纳米管的表面引入了苯乙烯马来酸酐共聚物. 经IR, Raman, TG和TEM测定, 证明了碳纳米管与苯乙烯马来酸酐共聚物之间为化学键连接关系.     

Y2O3薄膜处理对3Cr25Ni7N合金的抗高温氧化性能的影响

采用电沉积-热解法在3Cr25Ni7N合金表面制备了Y2O3薄膜,并研究了薄膜处理对合金在1000℃空气中的抗高温氧化性能的影响。氧化动力学曲线、SEM及XRD分析结果表明,Y2O3薄膜处理使合金表面氧化膜以尖晶石结构为主,氧化膜致密,有效地抑制了Cr2O3的挥发反应,且氧化膜与基体的附着性好,因此合金在高温下的抗氧化性能得到提高,这与氧化钇薄膜在较低温度下抗高温氧化性能提高的机制是不同的。在不同温度下,Y2O3薄膜处理均可以有效提高合金的抗高温氧化性能。     

Blood compatibility and permeability of heparin-modified polysulfone as potential membrane for simultaneous hemodialysis and LDL removal

Heparin was covalently immobilized on PSf membranes to obtain a dialysis membrane with high affinity for LDL. WCA and streaming potential measurements were performed to investigate wettability and surface charge of the membranes. The morphology of the membranes was investigated by SEM. An ELISA was used to measure the adsorption and desorption of LDL on plain and modified PSf. Blood compatibility was studied by measurement of thrombin time, partial thromboplastin time, kallikrein activity and platelet adhesion. It was found that the blood compatibility of the membrane was improved by covalent immobilization of heparin at its surface. However, PSf-Hep membrane showed higher flux recovery after BSA solution filtration, which revealed antifouling property of PSf-Hep membranes.     

基于多巴胺自聚合及肝素固定改善钛的血液相容性

利用多巴胺自聚合及肝素固定的方法对纯钛进行表面修饰, 以改善其血液相容性. 采用水接触角测量、 X射线光电子能谱(XPS)和甲苯胺蓝法(TBO)等方法对所修饰的材料进行了表征. 采用溶血实验检测了材料的溶血性能, 并结合活化部分凝血活酶时间(APTT)测试和血小板黏附实验对所修饰材料的血液相容性进行了评价. 结果表明, 多巴胺能够在钛表面实现自聚合, 肝素可以共价接枝在聚多巴胺层上, 经肝素修饰后的材料的表面亲水性显著提高, 而且具有较低的溶血率, APTT时间显著延长, 血小板的黏附数量和被激活程度也显著降低. 因此, 纯钛经多巴胺自聚合以及肝素接枝修饰后的血液相容性得到了显著改善, 有望成为具有抗凝血功能的新型心血管植入材料.     

Propionic Anhydride Modification of Cellulosic Kenaf Fibre Enhancement with Bionanocarbon in Nanobiocomposites

The use of chemical modification of cellulosic fibre is applied in order to increase the hydrophobicity, hence improving the compatibility between the fibre and matrix bonding. In this study, the effect of propionic anhydride modification of kenaf fibre was investigated to determine the role of bionanocarbon from oil palm shell agricultural wastes in the improvement of the functional properties of bionanocomposites. The vinyl esters reinforced with unmodified and propionic anhydride modified kenaf fibres bio nanocomposites were prepared using 0, 1, 3, 5 wt% of bio-nanocarbon. Characterisation of the fabricated bionanocomposite was carried out using FESEM, TEM, FT-IR and TGA to investigate the morphological analysis, surface properties, functional and thermal analyses, respectively. Mechanical performance of bionanocomposites was evaluated according to standard methods. The chemical modification of cellulosic fibre with the incorporation of bionanocarbon in the matrix exhibited high enhancement of the tensile, flexural, and impact strengths, for approximately 63.91%, 49.61% and 54.82%, respectively. The morphological, structural and functional analyses revealed that better compatibility of the modified fibre–matrix interaction was achieved at 3% bionanocarbon loading, which indicated improved properties of the bionanocomposite. The nanocomposites exhibited high degradation temperature which signified good thermal stability properties. The improved properties of the bionanocomposite were attributed to the effect of the surface modification and bionanocarbon enhancement of the fibre–matrix networks.     

Modification of PP by blending with PS and reactive polymers

In this paper a polypropylene (PP) resin with controlled rheology was selected as polymer matrix and modified by melt mixing with polystyrene (PS) which has certain processing compatibility with PP. The effect of the addition of polyperoxide (PPX), peroxide modified PS particles (PS‐PPX), and maleic anhydride (MAH) to the PP/PS blend during melt mixing on the rheological behavior and morphology of the PP/PS blends has been carefully studied.     

Covalent heparin modification of a polysulfone flat sheet membrane for selective removal of low-density lipoproteins: a simple and versatile method

A simple, convenient and economical method for the heparinization of PSf membranes is described, with the aim of preparing an LDL adsorber for simultaneous LDL apheresis and hemodialysis. An atmospheric pressure glow discharge generator is used to activate the PSf membrane surface, with subsequent chemical binding of heparin in the presence of EDC and NHS. ATR-FTIR spectroscopy and XPS measurements confirm successful surface modification. The PSf-Hep membrane shows good blood compatibility, with a relatively low amount and normal morphology of adherent platelets. ELISA results indicate that the PSf-Hep membrane exhibits excellent selective affinity for LDL in single and binary protein solutions, suggesting potential applications in hemodialysis with simultaneous LDL removal.     

几种修饰剂共价修饰L—门冬酰胺酶降低其抗原性的对比研究

选用单甲氧基聚乙二醇、右旋糖苷、磺化右旋糖苷,肝素及小分子醋酸酐对酶分子进行了共价修饰,研究了不同修饰剂对酶分子的酶活力及其抗原性的影响。结果表明,大分子,特别是单甲氧基聚乙二醇的降低抗原性效果很好,但活力损失较大;修饰剂分子量越大,酶表面氨基修饰程度越高,解除抗原性效果越好。     

Hemocompatibility and ultrafiltration performance of PAN membranes surface‐modified by hyperbranched polyesters

Maleic anhydride was grafted onto a polyacrylonitrile (PAN) membrane surface via ultraviolet irradiation. Then, hyperbranched polyester, with varying numbers of hydroxyl end‐groups (H20, H30, and H40), was grafted onto the PAN membrane surface by the reaction of hydroxyl groups with anhydride groups of maleic anhydride. The modified membranes were characterized by scanning electron microscopy, static water contact angle, and attenuated total reflectance‐Fourier transform infrared spectroscopy measurements. The modified membranes showed a higher water flux and better antifouling properties than pristine PAN membranes, and their hydrophilicity was significantly improved. Membrane biocompatibility was characterized by platelet adhesion, and the results indicate that the modified membranes exhibited good biocompatibility. Copyright © 2016 John Wiley & Sons, Ltd.     

Preliminary study of extractable protein binding using maleic anhydride copolymer

A preliminary study of using maleic anhydride copolymer for protein binding has been carried out.The polymeric films were prepared by compression of the purified resin and annealing the film to induce efficient back formation of the anhydride groups.The properties of the film surface were analyzed by attenuated total reflection Fourier transforms infrared spectroscopy and water contact angle measurements.The protein content was determined by Bradford assay.To obtain optimum conditions,immersion time for protein binding was examined.Results revealed that proteins can be successfully immobilized onto the film surface via covalent linkage.The efficiency of the covalent binding of the extractable protein to maleic anhydride-polyethylene film was estimated at 69.87μg/cm~2,although the film had low anhydride content(3%) on the surface.     

化学修饰壳聚糖的血液相容性

壳聚糖是无毒、可生物降解、具有生物相容性的天然碱性多糖。本文综述了近年来提高壳聚糖的血液相容性的方法及以壳聚糖为原料制备肝素替代品的研究。壳聚糖分子上接枝血液相容性高分子、引入亲水基团或负电基团、酰化改性等均能提高壳聚糖的血液相容性;以壳聚糖为原料制备肝素的替代品可通过在壳聚糖分子上引入磺酸基,或将壳聚糖氧化成6-羧基壳聚糖后再引入磺酸基来实现。对今后如何进一步提高壳聚糖衍生物的血液相容性研究前景进行了展望。     

酸酐化聚砜对聚砜/液晶聚合物共混物的界面增容作用

首先合成了马来酸酐接枝改性聚砜.改性后聚砜材料的表面张力增大,其中的极性分量增加明显,并以此增容聚砜/液晶聚合物(VectraB950)为原位复合体系,研究了增容前后共混物的加工流变行为和界面性能.结果表明,酸酐化聚砜可增强聚砜与液晶聚合物之间的界面作用,引起共混物加工粘度的上升;漫反射FTIR研究表明,增容后共混体系中的特殊相互作用增大;XPS和PLM的研究表明,在熔融加工过程中改性聚砜与液晶聚合物组分之间存在一定的界面化学反应,并生成了接枝共聚物.共混物相容性的提高应归结于相间化学反应与物理作用共同作用的结果.