应用于塑料基材的溶剂型双组分聚氨酯柔感涂料

通过对树脂、助剂和固化剂进行筛选,获得了适用于塑料基材的溶剂型双组分聚氨酯柔感涂料配方。测试了涂膜的各项性能。结果表明,该双组分柔感涂料具有附着力佳、手感细腻滑爽、抗划伤力强以及优异的耐腐蚀等性能。讨论了柔感涂料施工过程中常见的问题及其解决办法。     

Polymer porous thin films obtained by direct spin coating

Films of four different nanostructures, namely micelles, filled cylinders, ring‐shaped porous nanostructures and hollow cylinders, can be prepared easily in a straightforward and simple way by spin coating onto a silicon plate toluene solutions of poly(styrene‐block‐4‐vinylpyridine) copolymer containing formic acid of increasing concentration. Despite the enormous progress in preparation of porous polymers, most of them require multiple steps. In this sense, this method represents an effort to obtain not only porous thin films but also other bidimensional nanostructures in a very simple way. © 2017 Society of Chemical Industry     

The co-micelle/emulsion templating route to tailor nano-engineered hierarchically porous macrospheres

Here we present a new class of nano-engineered hierarchically porous materials in which the entire framework is mesoporous. This material is engineered into macrospheres of controllable size with a highly interconnected macropore network to facilitate molecular diffusion access. To achieve this, a new co-micelle/emulsion templating (co-MET) technique was developed. In this technique a block copolymer plays the dual roles of emulsion stabilization and micelle formation within the aqueous phase of that emulsion to produce the hierarchical structures. The emulsion templating provides the macroporous structure while the mesoporous structure is formed by hydrolyzation of silica around block copolymer micelles. Increasing the copolymer concentration improves the mesoporosity up to a certain concentration where the emulsion phase behavior changes and the macroporosity is affected. Unlike other hierarchically porous materials, the walls of the co-MET macrospheres are entirely mesoporous, which provides high surface areas (>500 m² g⁻¹) and pore volumes (>1 cm³ g⁻¹) and narrow mesopore size distributions (∼10 nm). This interconnected hierarchical meso/macroporous structure combined with the controlled particle size makes this new class of materials promising for applications requiring high diffusion and throughput rates, alleviating the problems of using typical fine particle mesoporous materials.     

热处理工艺对减反膜性能的影响

以本实验室制备的高性能减反膜为研究对象,利用溶胶一凝胶法合成SiO：溶液,采用高速旋涂法制备纳米多孔SiO2减反膜,测试结果表明涂覆在白玻基材上的减反膜在可见光波段（400～800nm）范围内的透过率为94．6％±0．3％,其在405nm波长处的透过率达到1198．27％;同时进一步研究了热处理工艺在减反膜涂覆阶段对其减反性能的影响,研究发现：如果在基材表面涂覆一定厚度的减反膜,不同的热处理工艺对其的减反效果影响很大;如果热处理工艺选择不当,会使最终得到的涂层失去减反效能,甚至大幅度降低基材本身的透过率,为84．9％±1．1％。     

辊式涂布法构建纸基牢固超疏水表面

采用辊式涂布的方法在纸基材料上构建超疏水表面,并对超疏水表面的牢固性、自清洁性和疏水性能进行评价。用γ-氨丙基三乙氧基硅烷和1H,1H,2H,2H-全氟辛基三乙氧基硅烷（POTS）对微米级和纳米级两种尺寸的TiO₂粒子进行疏水改性处理,然后将改性后的微/纳米TiO₂涂布在纸基材料表面。采用红外光谱（FTIR）对改性后的微/纳米TiO₂的化学组成进行了分析,采用扫描电镜（SEM）对涂布纸表面结构进行了表征,通过接触角、耐磨性和自洁净测试评价了涂层表面的超疏水性、牢固性和自清洁性。改性TiO₂的FTIR分析显示在1000～1500cm^-1之间出现多个C—F键的伸缩振动峰,表明POTS通过化学键与TiO₂表面发生了结合。涂布纸表面的SEM分析可以看出,纸基材料表面上均匀分布了微米和纳米尺寸的TiO₂颗粒,具备了类似荷叶表面微-纳结构的粗糙表面。涂层表面的水接触角为153°±1.5°,滚动角为3.5°±0.5°,水滴在涂层表面呈球形,极易滑落,涂层在水中浸泡7天后,接触角没有发生明显变化,表明纸张表面具备了优异的超疏水性能,且疏水稳定性较好。涂层表面经过10次循环磨损试验后,接触角仍能达到150°,滚动角为9°,表明机械摩擦没有对涂布纸表面的化学成分和粗糙结构造成明显的破坏,超疏水表面的牢固性较好。自洁净测试表明,涂布纸表面具有良好的自清洁和防污性能。该工艺过程操作简单,易于实现工业化生产,为在纸基表面构建综合性能优异的超疏水表面提供了一种新的便利途径。     

High capacitance properties of polyaniline by electrochemical deposition on a porous carbon substrate

Electrochemical deposition of polyaniline (PANI) is carried out on a porous carbon substrate for supercapacitor studies. The effect of substrate is studied by comparing the results obtained using platinum, stainless steel and porous carbon substrates. PANI deposited at 100 mV s⁻¹ sweep rate by potentiodynamic technique on porous carbon substrate is found to possess superior capacitance properties. Experimental variables, namely, concentrations of aniline monomer and H₂SO₄ supporting electrolyte are varied and arrived at the optimum concentrations to obtain a maximum capacitance of PANI. Low concentrations of both aniline and H₂SO₄, which produce PANI at low rates, are desirable. The PANI deposits prepared under these conditions possess network morphology of nanofibrils. Capacitance values as high as 1600 F g⁻¹ are obtained and PANI coated carbon electrodes facilitate charge-discharge current densities as high as 45 mA cm⁻² (19.8 A g⁻¹). Electrodes are found to be fairly stable over a long cycle-life, although there is some capacitance loss during the initial stages of cycling.     

Preparation and characterization of delafossite CuCrO2 film on flexible substrate

Delafossite CuCrO₂ film was successfully prepared on a flexible plastic substrate using a heat transfer process. The metallic acetate of the first layer decomposed to form a carbonized layer for use as a release layer. The thin film was deposited on the first layer by chemical solution deposition and heat treated to form a CuCrO₂ film. After that, the delafossite CuCrO₂ film was transferred from a Si substrate to a polymethyl methacrylate (PMMA) substrate. The CuCrO₂/PMMA film structure, morphology, and optical properties were studied by different characterization techniques. X-ray diffraction analysis and Raman spectrum analysis confirmed that the delafossite CuCrO₂ film was transferred onto the PMMA substrate. XPS analysis showed that the metallic acetate was annealed in N₂ to form a carbonized layer. The resistivity of the CuCrO₂/PMMA was gauged by a four-point probe method, and the visible light transmittance was approximately 58%.     

Large-scale preparation of nanoporous TiO2 film on titanium substrate with improved photoelectrochemical performance

Fabrication of three-dimensional TiO₂ films on Ti substrates is one important strategy to obtain efficient electrodes for energy conversion and environmental applications. In this work, we found that hierarchical porous TiO₂ film can be prepared by treating H₂O₂ pre-oxidized Ti substrate in TiCl₃ solution followed by calcinations. The formation process is a combination of the corrosion of Ti substrate and the oxidation hydrolysis of TiCl₃. According to the characterizations by scanning electron microscopy (SEM), X-ray diffraction (XRD), and diffuse reflectance spectroscopy (DRS), the anatase phase TiO₂ films show porous morphology with the smallest diameter of 20 nm and possess enhanced optical absorption properties. Using the porous film as a working electrode, we found that it displays efficient activity for photoelectrocatalytic decolorization of rhodamine B (RhB) and photocurrent generation, with a photocurrent density as high as 1.2 mA/cm². It represents a potential method to fabricate large-area nanoporous TiO₂ film on Ti substrate due to the scalability of such chemical oxidation process.     

塑料粉末涂料与具有塑料涂敷层的大型金属容器

介绍了对大型金属容器现场涂敷的方法以及关于金属－塑料复合膜的新技术。     

淀粉基底银纳米线柔性透明导电薄膜的合成及光电性能

以马铃薯淀粉为原料,合成可反复弯曲折叠的柔性透明基底膜,通过多元醇法制备导电银纳米线(Ag NW),用旋涂法将Ag NW均匀覆盖于淀粉基底膜表面,两者通过分子间作用力相结合,制得系列Ag NW沉积密度不同的复合导电薄膜材料。对产品形貌、结构及稳定性进行了分析,并探索了不同AgNW沉积密度对复合导电薄膜材料光电性能的影响规律。结果表明,获取的柔性基底膜具有92%透光率、3.92 nm粗糙度、29.01 MPa拉伸应力;导电银纳米线直径约60 nm,长度20～30μm。当Ag NW沉积密度超过300 mg/m2时,方块电阻(Rs)低于22.6?/sq,透光率低于65%,光电优值(FOM)高于35,是氧化铟锡(ITO)导电膜的良好替代材料。将复合膜反复弯曲折叠Rs变化量低于5%,TGA测试发现,淀粉基底膜及复合膜热分解温度高于250℃,有利于对其进行进一步高温导电处理;稳定性测试结果表明,复合膜放置于空气中随时间延长Rs略微增大。     

柔性纳米银线导电薄膜的制备及其性能研究

通过2步加入多元醇热还原法制备出了高长径比的纳米银线,并在柔性基材上制备兼具透光性和导电性的薄膜;对薄膜与基材的粘接性能进行了改善。采用X-射线衍射(XRD)、扫描电子显微镜(SEM)、场发射透射电子显微镜(FETEM)对纳米银线的相结构及形貌进行了分析及表征。薄膜的透光率和导电性分别通过紫外-可见分光光度计和四探针进行了研究。制备的纳米银线的直径约为50 nm,长径比为200~300。研究了银线浓度以及用量对真空抽滤转移法制备薄膜的透光率及导电性的影响,发现当银纳米线的浓度为0.025mg/mL,薄膜的透光率为71.0%时,方块电阻为65.5Ω/sq。所制备的薄膜在基材上的粘接性通过旋涂一层聚偏氟乙烯(PVDF),并经热处理后,粘接性和导电性(方阻为18.0Ω/sq)都有所提高。     

Enhanced photoluminescence of porous silicon nanoparticles coated by bioresorbable polymers

A significant enhancement of the photoluminescence (PL) efficiency is observed for aqueous suspensions of porous silicon nanoparticles (PSiNPs) coated by bioresorbable polymers, i.e., polylactic-co-glycolic acid (PLGA) and polyvinyl alcohol (PVA). PSiNPs with average size about 100 nm prepared by mechanical grinding of electrochemically etched porous silicon were dispersed in water to prepare the stable suspension. The inner hydrophobic PLGA layer prevents the PSiNPs from the dissolution in water, while the outer PVA layer makes the PSiNPs hydrophilic. The PL quantum yield of PLGA/PVA-coated PSiNPs was found to increase by three times for 2 weeks of the storage in water. The observed effect is explained by taking into account both suppression of the dissolution of PSiNPs in water and a process of the passivation of nonradiative defects in PSiNPs. The obtained results are interesting in view of the potential applications of PSiNPs in bioimaging.     

聚合物电解质的研究进展

介绍了锂离子电池的特点、市场前景及聚合物锂离子电池的种类,综述了聚合物电解质的发展历程,重点阐述了近来研究较多的几种聚合物电解质的研究进展,包括:聚偏氟乙烯基(PVDF基)、聚丙烯腈基(PAN基)、聚甲基丙烯酸甲酯基(PMMA基)和聚乙烯类(PE)聚合物电解质。     

高聚物球晶的研究

利用偏光显微镜 ,对高聚物 (PP ,PS和PE)在不同条件进行熔融结晶时的球晶进行了研究。结果表明 :温度、应力及杂质对球晶的形态、大小、多少、分布均有影响。同时对试验结果进行了理论分析     

Fabrication of high performance Pt counter electrodes on conductive plastic substrate for flexible dye-sensitized solar cells

Pt counter electrodes (CEs) with different platinum loading have been prepared using chemical reduced method on flexible indium-doped tin oxide coated polyethylene naphthalate (ITO-PEN) for dye-sensitized solar cells (DSSCs). H₂PtCl₆·6H₂O terpineol solutions were screen printed on the transparent ITO-PEN substrates. After drying, H₂PtCl₆ was reduced by treating it in NaBH₄ solution followed by the hydrothermal treatment at 100 °C. The obtained Pt CEs with different Pt-loading (2.4-7.7 μg/cm²) were characterized by SEM, XPS, electrochemical impedance and transmission spectrum measurement. The Pt CEs show high catalytic activity, low charge transfer resistance (0.26-1.38 Ω cm²) and good light transmittance (about 70% at 400-800 nm). The light-to-electricity conversion efficiency of the flexible DSSC fabricated with the prepared Pt CE and the TiO₂ photoanode prepared on Ti substrate by screen printing technique attains 5.41% under the simulated AM 1.5 sunlight, which is almost same as that based on the thermal decomposited Pt CE on FTO-glass. Compared with other methods to prepare Pt CEs, chemical reduced method is simple and suitable for flexible polymer substrates and the large scale preparation of DSSCs.     

蓝宝石玻璃减反射膜的制备与性能

采用真空蒸发镀技术在蓝宝石玻璃单面和双面分别沉积了1层(MgF2)、2层(Al2O3-MgF2)和4层(Al2O3-H4-Al2O3-MgF2)减反射膜,讨论了极限温度、紫外光老化、腐蚀和摩擦对镀膜蓝宝石玻璃透过率的影响.结果表明,镀减反射膜后,蓝宝石玻璃的透过率得到提升,双面镀膜的透过率比单面镀膜高出6个百分点.经各...     

Cracked titanium film on an elastomeric substrate for highly flexible,transparent, and low-power strain sensors

Strain-dependent cracking behaviors in thin titanium (Ti) films on polydimethylsiloxane (PDMS) substrates were systematically investigated for their application to sensitive, flexible, transparent, and portable strain sensors. When uniaxially elongated, vertical cracks were developed in the low-strain range, and beyond a critical strain, tilted cracks appeared to intersect the vertical cracks. The cracking behaviors were also dependent on Ti film thickness. The varying strain-dependent crack patterns produced a significant resistance change in response to the applied strain, particularly, in the high- and broad-strain range. For a 180-nm-thick Ti film on PDMS substrate, a gauge factor of 2 was achieved in the range of 30% to 50% strain. The operation power was extremely low. All the Ti films on PDMS substrates were transparent, highly flexible, and very easy to fabricate. These results suggest that cracked Ti films on PDMS substrates could be a viable candidate for realizing a low-cost, flexible, transparent, and portable strain sensor.     

Shear-thinning film on a porous substrate: Stability analysis of a one-sided model

The temporal stability of a Carreau fluid flowing down an inclined porous substrate is considered. A reduced model is derived under the assumption of small permeability which decouples the flow in the liquid layer from the filtration flow in the porous medium and incorporates the effect of the porous medium by means of an effective slip condition at the liquid–solid interface. The slip coefficient in the effective slip condition is a function of the structure, permeability of the porous medium and the rheology of the fluid saturating the porous medium. The effects of shear-thinning rheology and permeability of the substrate on the stability of the film flow system are investigated. This problem gives rise to a generalized eigenvalue formulation which is solved through two approaches. The problem is solved analytically for long waves in the limiting cases of weakly and strongly non-Newtonian behaviors (power-law limit). A numerical investigation is carried out in the general case. The results are shown to agree well for the weakly non-Newtonian limit. Further, the power-law model and the Carreau model agree on a wide range of shear-thinning parameter values for a thin film over a rigid substrate. However, when considering a porous medium, this trend is not observed. The Carreau model gives valid results for the entire range of shear-thinning parameter values for a film over a rigid/porous substrate. The novelty of the present investigation lies in the inclusion of both the effects of bottom permeability and shear-thinning rheology. Both permeability and shear-thinning rheology have a destabilizing effect on the film flow system. The numerical results indicate the correlation between the effects due to shear-thinning properties and permeability. An energy balance analysis performed on the perturbation fields shows that destabilization induced by both shear-thinning and permeability is linked to the viscous shear work rate on the free surface.     

高分子物理精品课程建设

精品课程建设是衡量学校办学水平和教学质量的重要标志,是实现培养目标的基本保证。作者从教学内容、教学条件、教学方法及教学效果等方面,对高分子物理精品课程建设进行了探讨和实践。     

Polymer Film Heat Transfer Surfaces in Seawater Desalination: Fouling Layer Formation and Technology

The emerging polyether ether ketone (PEEK) films were evaluated as future heat exchanger materials in seawater thermal desalination processes. Fouling resistance curves were measured in a pilot plant for pure PEEK films, talcum-filled PEEK films, and stainless-steel films with artificial seawater, showing that pure PEEK films have the advantage of weaker forces of adhesion or cohesion between the scaling materials and the film surface. Increasing the flow rate from 18 to 24 L min⁻¹ results in decreases of both the fouling rate and the asymptotic values. This was attributed to the lower polarity of 10.4 %, the lower arithmetic average roughness of 0.06 μm, and the homogeneous topography of the PEEK film. This polymer film is adaptable to in situ cleaning in thermal seawater desalination processes.