聚合物基纳米复合材料的合成、性质及应用前景

介绍了聚合物 无机纳米复合材料、聚合物 /聚合物纳米复合材料的制备方法、性质、发展方向以及应用前景。对聚合物基纳米复合材料今后的发展提出了一些自己的见解     

含铁聚合物薄膜的制备、结构和性能

采用等离子体增强金属有机化合物化学气相沉积（PEMOCVD）工艺制备含铁聚合物薄膜。考察了偏压、源物加热电压对膜的沉积速率及膜中Fe的填充系数的影响。用IR，XPS，TEM和TED对膜的组成和结构进行了分析，表明薄膜具有Fe团簇镶嵌在聚合物基质中的杂混结构特征。对薄膜的光学、电学及湿敏特性进行了研究，证明膜的填充系数对膜的结构和性能都有很大的影响。该薄膜具有较好的湿敏性能。     

Chemical Vapor Deposition of Conformal,Functional, and Responsive Polymer Films

Chemical vapor deposition (CVD) polymerization utilizes the delivery of vapor‐phase monomers to form chemically well‐defined polymeric films directly on the surface of a substrate. CVD polymers are desirable as conformal surface modification layers exhibiting strong retention of organic functional groups, and, in some cases, are responsive to external stimuli. Traditional wet‐chemical chain‐ and step‐growth mechanisms guide the development of new heterogeneous CVD polymerization techniques. Commonality with inorganic CVD methods facilitates the fabrication of hybrid devices. CVD polymers bridge microfabrication technology with chemical, biological, and nanoparticle systems and assembly. Robust interfaces can be achieved through covalent grafting enabling high‐resolution (60 nm) patterning, even on flexible substrates. Utilizing only low‐energy input to drive selective chemistry, modest vacuum, and room‐temperature substrates, CVD polymerization is compatible with thermally sensitive substrates, such as paper, textiles, and plastics. CVD methods are particularly valuable for insoluble and infusible films, including fluoropolymers, electrically conductive polymers, and controllably crosslinked networks and for the potential to reduce environmental, health, and safety impacts associated with solvents. Quantitative models aid the development of large‐area and roll‐to‐roll CVD polymer reactors. Relevant background, fundamental principles, and selected applications are reviewed.     

聚合物及聚合物基复合材料电树模拟

介绍了国内外电树模拟的发展情况.概括出电树模拟的一般过程,将电树模拟的基本方法归纳为点阵 模拟法、非点阵模拟法、细胞模拟法和网格模拟法,分析了4种模拟方法的优缺点,并针对4种模拟方法阐述了4种典型电树模型.     

Polymer matrix,polymer ribbon-reinforced transparent composite materials

Composites of a polymer–matrix reinforced by polymer ribbon monofilaments are investigated as mechanically robust, transparent composite materials. Transparent nylon monofilaments are mechanically worked to form flattened nylon ribbons, which are then combined with index-matched epoxy resin to create transparent composites. A range of optical and mechanical experiments are performed on composites and surrogate systems in order to quantify properties and guide system design. The results show that these polymer–polymer composites provide good transparency over a wide temperature range, and superior ballistic penetration resistance compared to monolithic transparent polymers.     

聚合物/聚合物纳米复合材料的研究进展

介绍了聚合物／聚合物纳米复合材料的特性,以及其最新进展,对聚合物纳米复合材料今后的发展提出了一些见解。     

新型二茂铁酒石酰腙聚合物的合成、表征及应用

通过1,1′-二乙酰基二茂铁与酒石酸二甲酰肼反应合成二茂铁酒石酰腙聚合物(Fc-JS)后,再与金属(M=Cu、Co、Ni、Mn、Cd)乙酸盐配位,得到5种二茂铁酒石酰腙金属配位聚合物(Fc-JS-M)。用IR、TGA、XRD、荧光光谱及介电常数进行表征。结果表明,在适于移动通信应用的0.2～2.0GHz频段,Fc-JS-M有较高的介电常数(ε′)、较低的介电损耗(ε″),将其制成的倒F型微带天线有良好的缩波性能和较高的增益。因此Fc-JS-M作为一种天线新材料,可用于小型化、多功能化及高增益的双频微带天线。     

具有UV探测灵敏性、稳定性和重复利用性的层状铀酰配位聚合物研究

灵敏的UV探测对于工业生产和个人防护非常重要, 本研究旨在开发新型UV探测材料。一般而言, 铀酰单元具有相对高的UV吸收效率和荧光强度。本课题组成功地在水热条件下制备了一例铀酰配位聚合物[(TEA)₂(UO₂)₅(PhPC)₆] (TEA = 四乙基胺离子, PhPC = (2-羧基乙基)苯膦酸, 标记为UPhPC-1)。基于单晶XRD数据的结构分析表明UPhPC-1中有三个不同的铀酰中心, 其中两个铀酰单元为五角双锥构型, 而第三个铀酰单元为四角双锥构型。全部三个铀酰中心与配体在[bc]平面配位形成无限的铀酰层。通过氢键网格和π-π相互作用, 这些铀酰层堆积成整体的层状结构。此化合物具有很好的热稳定性、水稳定性和高抗辐照能力。UV辐照实验结果表明UPhPC-1的本征荧光强度对365 nm的UV辐射高度敏感, 检测下限低且响应速率快, 而发光强度与UV辐照剂量呈负相关。电子顺磁共振谱分析证实在UV光照射下, UPhPC-1中极有可能产生自由基, 造成铀酰荧光部分淬灭。进一步, 被淬灭样品中的自由基能够在加热后被去除, 从而实现UPhPC-1发光强度的快捷恢复。目前的结果表明UPhPC-1在UV辐照的定量探测领域具有一定的发展潜力。     

Polymer foams for personal protection: cushions, shoes and helmets

Three areas, where polymer foam products are used in personal protection, are reviewed to contrast the foam micromechanisms and the use of Finite Element Analysis (FEA) for engineering design. For flexible open-cell foams used for seating cushions, the main deformation mechanism is cell edge bending; regular cell models can predict much of the compressive response. Hyperelastic FEA models can then predict the forces for foam indentation. For flexible closed-cell foams used in shoe midsoles, cell air compression dominates the response; diffusive air loss leads to foam deterioration with use. Hyperelastic FEA models can predict the interaction between the foam and the heelpad. Finally, for rigid closed-cell foams used in helmets, the permanent stretching and wrinkling of cell faces dominates the response. Crushable foam FEA models, which consider the yield surface and hardening, predict different responses for impacts on the road and on a kerbstone.     

Polymer nanocomposites processed via self-assembly through introduction of nanoparticles,nanosheets, and nanofibers

Nanocomposites offer the theoretical potential to achieve mechanical properties surpassing those of conventional (micro-scale) composites. The underlying reasons for the high potential of nanocomposites include the uniquely high mechanical attributes of nano-scale reinforcement, effective control of defect size and growth by nano-spaced interfaces, and interactions between the polymer matrix and the large surface areas of nanomaterials. Attempts to produce nanocomposites via conventional processing techniques have encountered challenges associated with thorough dispersion and effective interfacial interactions of nano-scale reinforcement with the polymer matrix. In order to address these challenges, materials were processed into polymer nanocomposites via electrostatically driven layer-by-layer self-assembly. Electrostatically dispersed nanomaterials and oppositely charged polyelectrolytes were sequentially built upon a substrate (cellular scaffold). The self-assembled nanocomposites, after complementary cross-linking, provided a unique balance of strength and ductility, which surpassed those of conventional (micro-scale) composites. Self-assembly was found to be an effective approach to producing nanocomposites embodying uniformly dispersed nanomaterials with controlled interfacial interactions. This approach is highly versatile and enables introduction of diverse nanomaterials into polymer nanocomposites. The work reported herein evaluated introduction of diverse categories of nanomaterials incorporating nanoparticles, nanosheets, nanotubes, and nanofibers. This investigation also evaluated the potential for a biomimetic approach to processing of light-weight structural systems by self-assembly of polymer nanocomposites onto cellular scaffolds.     

Advanced Subcompartmentalized Microreactors: Polymer Hydrogel Carriers Encapsulating Polymer Capsules and Liposomes

The design of compartmentalized carriers for advanced drug delivery systems or artificial cells and organelles is of interest for biomedical applications. Herein, a polymer carrier microreactor that contains two different classes of subcompartments, multilayered polymer capsules and liposomes, is presented. 50 nm‐diameter liposomes and 300 nm‐diameter polymer capsules are encapsulated into a larger polymer carrier capsule, demonstrating control over the spatial positioning of the subcompartments, which are either ‘membrane‐associated’ or 'free‐floating’ in the aqueous interior. Selective and spatially dependent degradation of the 300 nm‐diameter subcompartments (without destroying the structural integrity of the enzyme‐loaded liposomes) is also shown, by performing an encapsulated enzymatic reaction using the liposomal subcompartments. These findings cover several important aspects toward the development of engineered compartmentalized carrier vessels for the creation of artificial cell mimics or advanced therapeutic delivery systems.     

Polymer Carpets

The fabrication of defined polymer objects of reduced dimensions such as polymer‐coated nanoparticles (zero‐dimensional (0D)), cylindrical brushes (1D), and polymer membranes (2D), is currently the subject of intense research. In particular, ultrathin polymer membranes with high aspect ratios are being discussed as novel materials for miniaturized sensors because they would provide extraordinary sensitivity and dynamic range when sufficient mechanical stability can be combined with flexibility and chemical functionality. Unlike current approaches that rely on crosslinking of polymer layers for stabilization, this report presents the preparation of a new class of polymer material, so‐called “polymer carpets,” a freestanding polymer brush grown by surface‐initiated polymerization on a crosslinked 1‐nm‐thick monolayer. The solid‐supported, as well as freestanding, polymer carpets are found to be mechanically robust and to react instantaneously and reversibly to external stimuli by buckling. The carpet mechanics and the dramatic changes of the film properties (optical, wetting) upon chemical stimuli are investigated in detail as they allow the development of completely new integrated micro‐/nanotechnology devices.