Stable Li storage in micron-sized SiO_(x) particles with rigid-flexible coating

Micrometre-sized electrode materials have distinct advantages for battery applications in terms of energy density,processability,safety and cost.For the silicon monoxide anode that undergoes electrochemical alloying reaction with Li,the Li(de)intercalation by micron-sized active particles usually accompanies with a large volume variation,which pulverizes the particle structure and leads to rapidly faded storage performance.In this work,we proposed to stabilize the electrochemistry vs.Li of the micron-SiO_(x) anode by forming a rigid-flexible bi-layer coati ng on the particle surface.The coati ng consists of pyrolysis carbon as the inner layer and polydopamine as the outer layer.While the inner layer guarantees high structural rigidity at particle surface and provides efficient pathway for electron conduction,the outer layer shows high flexibility for maintaining the integrity of micrometre-sized particles against drastic volume variation,and together they facilitate formation of stable solid electrolyte interface on the SiO_(x) particles.A composite an ode prepared by mixing the coated micron-SiOx with graphite delivered improved Li storage performance,and promised a high-capacity,long-life LiFePO_(4)/SiO_(x)-graphite pouch cell.Our strategy provides a general and feasible solution for building high-energy rechargeable batteries from micrometre-sized electrode materials with significant volume variation.

Opto-Electronic Investigation of Wet Coating Deposition of ITO Nanopowders on Flexible Substrate Using Pulse Nd-YAG Laser

Transparent thin layer indium tin oxide was coated on polyethylene tetraphetalate (PET) substrate by means of spin coating process and its opto-electronic properties have been investigated. The surface treated by pulse Nd-YAG laser. Pulse frequency, duration and energy were, 1000 Hz, 0.2 to 20 ms and 25 to 40 J respectively. The effect of treatment on crystallization, optical properties and bonding processes of the thin layer was investigated. The results show that ITO coated on flexible PET substrates is conductive and transparent. The sheet transparency for a 350 nm thickness in the visible range is more than 83.6%. Using Nd-YAG laser increased conductivity by a factor of 100 times and causes higher bonding performances.

Flexible perovskite solar cells based on green,continuous roll-to-roll printing technology

By designing and fabricating thin film electronic devices on a flexible substrate instead of more commonly used rigid substrate, flexible electronics produced has opened a field of special applications. In this article, we first reviewed available products that may be used as flexible substrates, their characteristics and unique advantages as supporting material for flexible electronic devices. Secondly, flexible perovskite solar cell is examined in detail, with special focus on its potential large-scale fabrication processes. In particular, a comprehensive review is provided on low cost solution printing techniques that is viewed highly as a viable tool for potential commercialization of the perovskite solar cells. Furthermore, a summary is given on green processing for the solution printing production of flexible perovskite devices.

Scalable and fast fabrication of graphene integrated micro-supercapacitors with remarkable volumetric capacitance and flexibility through continuous centrifugal coating

Microscale electrochemical energy storage devices,e.g., micro-supercapacitors(MSCs),possessing tailored performance and diversified form factors of lightweight,miniaturization,flexibility and exceptional integration are highly necessary for the smart power sources-unitized electronics.Despite the great progress,the fabrication of MSCs combining high integration with high volumetric performance remains largely unsolved.Herein,we develop a simple,fast and scalable strategy to fabricate graphene based highly integrated MSCs by a new effective continuous centrifugal coating technique.Notably,the resulting highly conductive graphene films can act as not only patterned microelectrodes but also metal-free current collectors and interconnects,endowing modular MSCs with high integrity,remarkable flexibility,tailored voltage and capacitance output,and outstanding performance uniformity.More importantly,the strong centrifugal force and shear force generated in continuous centrifugal coating process lead to graphene films with high alignment,compactness and packing density,contributing to excellent volumetric capacitance of ~31.8 F cm^(-3) and volumetric energy density of ~2.8 mWh cm^(-3),exceeding most reported integrated MSCs.Therefore,our work paves a novel way for simple and scalable fabrication of integrated MSCs and offers promising opportunities as standalone microscale power sources for new-generation electronics.

Effect of Chitosan Coating on the Properties of Poly(glycolic acid-lactic acid)Thread-Embedding Material

Poly( glycolic acid-lactic acid)( PGLA) threadembedding material was modified by chitosan coating which could improve the rigidity,hydrophilicity and moisture absorption of the material,and produced better stimulation effect. Thus,this kind of thread-embedding materials which can be buried into acupuncture points to produce a long-time stimulation is popular in the acupuncture and moxibustion therapies. The variation tendencies of diameter,weight, hydrophilicity, and flexibility of the samples under the change of chitosan coating concentration,coating time and coating times were studied respectively. The results showed that the hydrophilicity,weight,and rigidity after coating rose in a certain range with the increase of coating time,coating times and coating concentration. The coating time had little influence on the diameter of fiber.

The Tribological Properties of the Hot-extrusion Nylon Coating in the Oil Well Environment

The friction and wear properties of the nylon coating,prepared by hot-extrusion, used to protect the surface of the flexible continuous sucker rod were studied by using a pin-on-disc wear tester in the simulated oil well environment.The effects of sliding speed and load were considered.The wear mechanism was also studied by using a scanning electron microscope (SEM).The result shows that the friction coefficients of both kinds of materials,JKPA and ZZ7024B,used to protect the surface of the flexible continuous sucker rod decrease with sliding speed increase,but change little with load increase in the simulated oil well environment.The value of friction coefficient of ZZ7024B is smaller than that of JKPA.The minimum value of friction coefficient of ZZ7024B is about 0.05.The wear volume of ZZ7024B is smaller than that of JKPA under the same conditions of experimentation.

丙烯酸硅烷酯柔性自抛光防污涂料制备及性能

以甲基丙烯酸甲酯、丙烯酸丁酯、丙烯酸异辛酯、丙烯酸甲氧基乙酯、丙烯酸三异丙基硅酯为单体,制备了丙烯酸硅烷酯基体树脂,将其与韧性树脂(液态聚丁二烯)共同作为成膜共混树脂,并以Cu_(2)O作为主要防污剂组分、吡啶硫酮铜(CuPT)和代森锌(Zineb)为辅助有机防污剂组分,配制了柔性自抛光防污涂料。对丙烯酸硅烷酯基体树脂进行了FTIR表征和玻璃化转变温度(Tg)测定,对成膜共混树脂进行了SEM测试,对柔性自抛光防污涂料进行了柔韧性、附着力、吸水率和防污性能测试。结果表明,丙烯酸硅烷酯基体树脂的Tg=–20.54℃时,具有较好的物理机械性能;韧性树脂可以作为外增塑手段增加丙烯酸硅烷酯基体树脂的柔韧性,当m(丙烯酸硅烷酯基体树脂)∶m(韧性树脂)=7∶3时,成膜共混树脂的相容性最好;柔性自抛光防污涂料柔韧性为1级,在弹性体基材表面附着力达到4.0 MPa;经过60 d测试,吸水率为1.1%~1.2%;浅海浸泡挂板36个月显示出明显的防污效果。

导电复合材料涂覆式全织物基柔性压阻传感器制备

针对目前织物基柔性压阻传感器制备工艺相对复杂、导电材料与织物结合度有限等问题,提出以聚二甲基硅氧烷(PDMS)-多壁碳纳米管(MWCNTs)/炭黑(CB)为导电复合材料涂覆非织造布制备压敏层,采用微滴喷射技术在织物表面直接成形叉指型金属电极,制备织物基柔性压阻传感器的方法。当CB与MWCNTs质量比为3∶2时,对不同MWCNTs填充量下导电复合材料形态及制备的压敏层微观形貌观察,并研究其对传感器灵敏度的影响,最后对制得传感器的性能及应用进行测试。结果表明:导电材料在PDMS中分散均匀,导电复合材料与织物结合紧密;当MWCNTs质量分数为2.5%时,所制传感器灵敏度最高可达0.353 kPa^(-1),检测范围为0~25 kPa,响应/恢复时间为150/200 ms,最低检测限约为49 Pa,具有良好的重复稳定性(约1 600次)。此外,该传感器可识别出手指按压以及手指和腕部弯曲的压力信号,可应用于人体健康、运动等信号监测。

硅包覆碳点基柔性发光太阳能聚光器的制备与性能研究

碳点由于环境友好、经济适用、合成方法简单及光学性能优异而在发光太阳能聚光器领域受到越来越多的关注。然而,碳点与亲水性聚合物波导材料相容作为发光基质时,多数碳点在聚合物中的相容性差,以及亲水聚合物的易脆性等问题严重限制发光太阳能聚光器的实际应用。为了解决这些问题,本文利用3-氨丙基三乙氧基硅烷的水解缩合,与邻苯二甲酸、邻苯二胺共同合成了一种斯托克斯位移为150 nm、量子产率为10.94%,且具有良好分散性和相容性的亮黄色发射硅包覆碳点;同时,以具有良好相容性、高柔韧性的聚二甲基硅氧烷为波导材料,二者结合制备出一系列尺寸为3 cm×3 cm×0.1 cm,不同质量百分比的硅包覆碳点柔性发光太阳能聚光器,其中,性能最佳的太阳能聚光器能量转换效率可达1.05%。这项工作将硅包覆碳点与聚二甲基硅氧烷的优势相结合,对发光太阳能聚光器实际应用有潜在价值。

柔性陶瓷涂料在盐湖钾盐生产设备的应用及耐蚀性能研究

盐湖资源开发过程中,金属材料腐蚀问题对设备的安全运转和生产的连续稳定运行造成很大危害。因此设备的腐蚀防护是盐湖资源开发的基本保障之一。以陶瓷颗粒为主要填料、改性环氧树脂为成膜物,开发出可应用于盐湖苛刻工况环境中的柔性陶瓷涂料,并对涂层基本物理机械性能和耐腐蚀性能进行研究。结果表明:柔性陶瓷涂料耐磨性好,在喷砂钢材表面附着力可达20.3 MPa,综合机械性能优良;涂层的耐化学溶剂性能良好,室温下,在10%NaCl溶液,10%NaOH溶液中浸泡30天后涂层表面无任何变化;在30%H_(2)SO_(4)溶液中浸泡30天后涂层有轻微变色,在10%HCl溶液中浸泡30天后涂层起泡,无红锈;应用于热溶生产氯化钾工艺中的浓密机底流泵管接头内壁防护,可有效提高设备的使用寿命。

柔性环氧沥青防腐涂料的制备及性能研究

混凝土防护工程表面涂层需要兼顾防水和防腐性能,且可以抵抗基层裂纹,市场上常见的柔性环氧防腐涂料主要适用于金属基材,具有一定柔性但没有延伸性,涂层易发生片状脱落。通过将乳化沥青、聚合物乳液和改性聚醚胺复配,制得高性价比且具有延伸性的柔性环氧防腐涂料。试验结果表明:当m(乳化沥青)∶m(聚合物乳液)∶m(改性聚醚胺)=48.2∶15∶10时,制备的防腐涂料25℃断裂伸长率达56.5%,低温柔性达-5℃;不透水性、耐腐蚀性和电化学阻抗测试结果表明,该涂料具有良好的耐水性和耐腐蚀性。

Progress in Polymer-Ceramic Hybrid Antifouling Coatings

Simultaneous realization of superior mechanical and antifouling properties is critical for a coating. The use of stereoscopic polysiloxanes in place of linear polysiloxanes to fabricate antifouling coatings can combine properties of organic and inorganic materials, i.e., they can exhibit both high hardness and wear resistance from inorganic components as well as the flexibility and tunability from organic components. This strategy is used to prepare hard yet flexible antifouling coatings or polymer-ceramic hybrid antifouling coatings. In this mini-review, we report the recent advances in this field. Particularly, the effects of stereoscopic polysiloxane structures on their mechanical and antifouling properties are discussed in detail.

旋涂法制备银纳米线柔性透明导电膜的研究

采用溶剂热法制备了长度50~170μm,直径50~110nm,长径比超过1000的银纳米线。以自制的银纳米线为导电相,聚醚改性后的聚硅氧烷润湿剂,无水乙醇为溶剂,配制银纳米线墨水。采用两步旋涂法在聚对苯二甲酸乙二醇酯基底上制备柔性透明银纳米线导电薄膜,并研究了旋涂层数、银纳米线浓度和用量、旋涂工艺对导电薄膜光电性能的影响。结果表明:旋涂层数和银纳米线浓度对薄膜的透光性有影响,银纳米线用量和二步旋涂速率对薄膜透光性影响不大,但是上述工艺条件对薄膜的导电性均有影响。在低速50r/s旋涂5s,再以500r/s加速到1000r/s旋涂15s的制备工艺条件下,3.5mol/L银纳米线溶液用量0.3mL且旋涂1层的薄膜在550nm处的透射率和方块电阻分别为87.8%和12.46Ω/□。分别经过800次向内和向外弯曲循环后,薄膜的方块电阻仍然很低。该研究工作为旋涂法制备高性能柔性透明AgNWs导电薄膜提供了指导。

单组分防水涂料用苯丙乳液的制备与研究

采用半连续滴加工艺合成了系列苯丙乳液,并应用于单组分防水涂料制备。研究了玻璃化温度设计、丙烯酰胺、丙烯酸、有机硅单体用量、乳化剂类型等因素对最终涂料性能的影响。结果表明:提高体系的玻璃化温度以及丙烯酰胺、丙烯酸和有机硅单体用量,所制得的单组分防水涂料拉伸强度提高,断裂伸长率下降;相较于阴离子乳化剂DB 45,DS-4AP十二烷基苯磺酸钠会导致漆膜吸水率大幅提高。将优化后的苯丙乳液制成单组分防水涂料,最终漆膜拉伸强度可达1.9 MPa,断裂伸长率400%,7 d吸水率8.5%,通过-20℃低温柔韧性试验,酸、碱处理后漆膜性能满足JC/T864—2008《聚合物乳液建筑防水涂料》的要求。

Slot-die coated large-area flexible all-polymer solar cells by nonhalogenated solvent

The slot-die coating is recognized as the most compatible method for the roll-to-roll(R2R)processing of large-area flexible organic solar cells(OSCs).However,the photovoltaic performance of the large-area flexible all-polymer solar cells was significantly lagging behind that of polymer donors with small molecule non-fullerene acceptors devices.In this work,the 1 cm^(2) flexible device of an all-polymer system,PTQ10:PYF-T-o,fabricated by slot-die coating,achieves an excellent efficiency of 11.24%via controlling the coating temperatures.It is found that,compared with the donor,the crystallinity of PYF-T-o plays a crucial role in device performance.The all-polymer flexible devices show superior mechanical bending stability,maintaining an efficiency of over 95%of the initial value during a 1000-cycle bending test.

地下室渗漏维修多道设防防水方案的应用

青岛某小镇联排建筑地下渗漏维修工程先采用排水、通风处理,然后对冷缝、底板、侧墙部位重新做防水处理,采用聚合物水泥防水砂浆+硅烷改性聚醚防水涂料+热塑性聚烯烃(TPO)防水卷材的多道设防防水做法,满足了项目防水需求。

国家游泳中心冬奥会冰壶场馆改造项目屋面天沟整修工程施工

基于国家游泳中心冬奥会冰壶场馆改造项目屋面天沟防水保温整修工程的应用实践,介绍了KEE防水卷材复合PMMA防水防腐涂料在暴露面应用的具体施工做法。该屋面天沟保温固定采用创新卡件,无需穿透天沟钢板;钢板接缝、落水斗、保温分仓等节点采用自粘EPDM防水卷材作加强处理;外层新设KEE防水卷材作为主防水层与原有PVC防水卷材搭接,PMMA防水防腐涂料加强封边,避免需拆除膜结构方可收口的困扰。

锂离子电池柔性负极材料CoO纳米线@C/碳布复合材料

本文提出了一种简便、可规模化制备CoO纳米线@C/碳布(CC)复合材料的方法,该复合材料可用作无粘结剂锂离子电池负极。首先通过简单的水热和煅烧法制备了CoO纳米线@碳布复合材料,再通过葡萄糖溶液浸渍和煅烧获得具有三维立体结构的CoO纳米线@C/CC复合电极材料。碳包覆的CoO纳米线均匀地分散在碳布上,形成导电的碳网络。在碳布上原位生长的CoO纳米线可以有效缩短锂离子的转移路径,降低接触电阻。碳涂层厚度约为1 nm,显著抑制了锂离子嵌入/嵌出过程中活性材料的粉碎,以及CoO在电解液中的直接暴露。结果表明CoO纳米线@C/CC复合材料用作锂离子电池的无粘结剂负极时,具有良好的充放电性能和循环稳定性。电流密度为1 A·cm^(-2)时,200次循环后的比容量为863 mAh·cm^(-2)(容量保持率75.83%)。本研究为柔性锂离子电池负极材料的制备提供了一种可行的新选择。

耐热线型小分子对有机硅耐温吸波涂层的增韧改性研究

目的采用能与有机硅单体反应的耐热小分子对苯基硅树脂基吸波涂层进行增韧改性,调控有机硅树脂的交联网络结构,并将改性树脂与耐温吸波剂复合,制备具有高柔韧、高附着力和耐温的吸波涂层。方法将不同端基或链长的耐热增韧剂通过硅氢加成接枝到有机硅树脂基体,改变基体的交联网络结构,通过红外、扫描电镜、万能电子试验机、动态热机械分析仪和矢量网络分析仪测试其性能。结果随着乙烯基封端聚二甲基硅氧烷含量的增加,涂层的柔韧性提高,但耐温性能和附着力降低;当乙烯基封端聚二甲基硅氧烷质量分数为45%时,1 mm涂层的柔韧性达20 mm,附着力达7.73 MPa,抗冲击性大于50 kg·cm。在300℃热处理15 h后,改性涂层挠度从未改性时的1.08 mm提升至1.35 mm,涂层在高温工作后仍保持较好的柔韧性。结论采用耐热线型小分子对有机硅树脂交联网络结构进行改性,可有效地调控耐温吸波涂层的力学性能,为耐高温吸波涂层增韧及其工程应用提供参考。