聚合物"刷子"的研究进展

采用活性聚合方法在材料表面制备聚合物"刷子"可有效控制材料表面性质,在分子结构设计中具有突出的优越性,所制备"刷子"的分子量可控、分布窄,近年来引起了研究者的广泛关注.主要综述了聚合物"刷子"的各种制备方法.     

In Pursuit of Zero: Polymer Brushes that Resist the Adsorption of Proteins

Protein resistant or “non‐fouling” surfaces are of great interest for a variety of biomedical and biotechnology applications. This article briefly reviews the development of protein resistant surfaces, followed by recent research on a new methodology to fabricate non‐fouling surfaces by surface‐initiated polymerization. We show that polymer brushes synthesized by surface‐initiated polymerization that present short oligo(ethylene glycol) side chains are exceptionally resistant to protein adsorption and cell adhesion. The importance of the protein and cell resistance conferred by these polymer brushes is illustrated by their use as substrates for the fabrication of antibody microarrays that exhibit femtomolar limits of detection in complex fluids such as serum and blood with relaxed requirements for intermediate wash steps. This example highlights the important point that the reduction in background noise afforded by protein‐resistant surfaces can greatly simplify the development of ultrasensitive heterogeneous, surface‐based clinical and proteomic assays with increased sensitivity and utility.     

Tip-Induced Nanopatterning of Ultrathin Polymer Brushes

Patterned, ultra-thin surface layers can serve as templates for positioning nanoparticlesor targeted self-assembly of molecular structures, for example, block-copolymers. This work investigates the high-resolution, atomic force microscopebased patterning of 2 nm thick vinyl-terminated polystyrene brush layers and evaluates the line broadening due to tip degradation. This work compares the patterning properties with those of a silane-based fluorinated self-assembled monolayer (SAM), using molecular heteropatterns generated by modified polymer blend lithography (brush/SAM-PBL). Stable line widths of 20 nm (FWHM) over lengths of over 20000 µm indicate greatly reduced tip wear, compared to expectations on uncoated SiO_x surfaces. The polymer brush acts as a molecularly thin lubricating layer, thus enabling a 5000 fold increase in tip lifetime, and the brush is bonded weakly enough that it can be removed with surgical accuracy. On traditionally used SAMs, either the tip wear is very high or the molecules are not completely removed. Polymer Phase Amplified Brush Editing is presented, which uses directed self-assembly to amplify the aspect ratio of the molecular structures by a factor of 4. The structures thus amplified allow transfer into silicon/metal heterostructures, fabricating 30 nm deep, all-silicon diffraction gratings that could withstand focused high-power 405 nm laser irradiation.     

原子转移自由基聚合法制备聚合物刷

介绍了原子转移自由基聚合法(ATRP)制备聚合物刷(平面刷、球形刷和分子刷)的研究进展及应用前景.聚合物刷子的奇异构象使其具有许多新奇的性质和潜在的应用前景.ATRP是制备具有可控结构的聚合物以及有机/无机杂化材料的一种较好的方法.通过ATRP制备聚合物刷,可以有效地改变聚合物刷的组成和聚合度,从而改变聚合物刷的表面性质,设计出具有新型结构及性能的材料.     

静电组装法在纳米SiO_2表面构筑高分子刷的合成与表征(英文)

本文采用静电自组装技术在表面阳离子化的SiO2粒子（SiO2-CBAFS）上构筑了高分子刷,并采用核磁、红外、热失重、接触角和原子力显微镜分别表征了组装粉体的结构、组装量以及自组装单层膜的组装行为和表面拓扑形貌。研究结果表明,采用静电自组装技术可以成功地在SiO2-CBAFS上构筑组装量高达27％的高分子刷,远远高于国际上已见报道的采用共价键合法构筑的高分子刷的组装量（20％）。研究发现,组装量随聚合物（PS-NH—SO3Na）分子量呈非线性增长,其组装行为受到PS-NH—SO3Na的分子量和溶液浓度的影响。     

球形高分子刷作为包装纸防潮涂料初探

目的以二氧化硅为核、聚甲基丙烯酸甲酯为刷制备球形高分子刷,考察其作为包装纸防潮涂料主要成膜物质的性能。方法采用"从表面接枝"技术,通过引发剂引发单体聚合生成甲基丙烯酸甲酯球形刷,利用FTIR和TEM对球形高分子刷的结构及形态进行表征,并考察其作为涂料成膜物质的应用性能。结果合成的球形高分子刷具有良好的耐水性能,且在固含量达到40%以上时仍具有较低的粘度(64 m Pa?s)。结论该球形高分子刷具有高固低粘包装纸防潮涂料的应用价值。     

高分子阻尼材料的研究进展

本文介绍了高分子阻尼材料的研究进展,包括复合阻尼材料、智能阻尼材料等.展望了高分子阻尼材料的发展前景.     

High‐ versus Low‐Quality Graphene: A Mechanistic Investigation of Electrografted Diazonium‐Based Films for Growth of Polymer Brushes

Electrografting using aryldiazonium salts provides a fast and efficient technique to functionalize commercially available 3?5 layered graphene (vapour‐deposited) on nickel. In this study, Raman spectroscopy is used to quantify the grafting efficiency of cyclic voltammetry which is one of the most versatile, yet simple, electrochemical techniques available. To a large extent the number of defects/substituents introduced to the basal plane of high‐quality graphene by this procedure can be controlled through the sweeping conditions employed. After extended electrografting the defect density reaches a saturation level (～10¹³ cm^?2) which is independent of the quality of the graphene expressed through its initial content of defects. However, it is reached within fewer voltammetric cycles for low‐quality graphene. Based on these results it is suggested that the grafting occurs (a) directly at defect sites for, in particular, low‐quality graphene, (b) directly at the basal plane for, in particular, high‐quality graphene, and/or (c) at already grafted molecules to give a mushroom‐like film growth for all films. Moreover, it is shown that a tertiary alkyl bromide can be introduced at a given surface density to serve as radical initiator for surface‐initiated atom transfer radical polymerization (SI‐ATRP). Brushes of poly(methyl methacrylate) are grown from these substrates, and the relationship between polymer thickness and sweeping conditions is studied.     

化学法制备导电高分子纳米复合材料研究进展

介绍了导电高分子纳米复合材料的特点及其设计原则,综述了化学法合成导电高分子纳米复合材料的最新进展,重点回顾了具有稳定胶体形式的导电高分子纳米复合材料和磁性导电高分子纳米复合材料的发展,探讨了导电高分子纳米复合材料未来的研究方向.     

聚合物/纳米粒子结构光伏电池的研究进展

从聚合物/纳米粒子结构光伏电池的工作原理出发,分别介绍了聚合物/富勒烯衍生物结构光伏电池和聚合物/无机半导体结构光伏电池各自的研究进展,同时比较了这2种结构光伏电池的性能,提出了目前开发聚合物/纳米粒子结构光伏电池所存在的问题与挑战.     

Hierarchically Branched Siloxane Brushes for Efficient Harvesting of Atmospheric Water

Atmospheric water harvesting is considered a viable source of freshwater to alleviate water scarcity in an arid climate. Water condensation tends to be more efficient on superhydrophobic surfaces as the spontaneous coalescence-induced droplet jumping on superhydrophobic surfaces enables faster condensate removal. However, poor water nucleation on these surfaces leads to meager water harvest. A conventional approach to the problem is to fabricate micro- and nanoscale biphilic structures. Nonetheless, the process is complex, expensive, and difficult to scale. Here, the authors present an inexpensive and scalable method based on manipulating the water-repellent coatings of superhydrophobic surfaces. Flexible siloxane can facilitate water nucleation, while a branched structure promotes efficient droplet jumping. Moreover, ToF-SIMS analysis indicated that branched siloxane provides a better water-repellent coating coverage than linear siloxane and the siloxanes comprise hydrophilic and hydrophobic molecular segments. Thus, the as-prepared superhydrophobic surface, TiO₂ nanorods coated with branched siloxanes harvested eight times more water than a typical fluoroalkylsilane (FAS)-coated surface under a low 30% relative humidity and performed better than most reported biphasic materials.     

高分子电池隔膜的研究进展

回顾了化学电源中高分子隔膜的发展,阐述了有机高分子隔膜在化学电源中的重要作用,对镍氢电池、锌银电池、锂离子电池及聚合物锂离子电池和燃料电池中各种高分子隔膜的性能、特点作了总结和评述,比较了其优缺点,并介绍了最新的研究进展.