Surface Morphology and Thermo-Electrical Energy Analysis of Polyaniline (PANI) Incorporated Cotton Fabric

With the exponential development in wearable electronics,a significant paradigm shift is observed from rigid electronics to flexible wearable devices.Polyaniline(PANI)is considered as a dominant material in this sector,as it is endowed with the optical properties of both metal and semiconductors.However,its widespread application got delineated because of its irregular rigid form,level of conductivity,and precise choice of solvents.Incorporating PANI in textile materials can generate promising functionality for wearable applications.This research work employed a straightforward in-situ chemical oxidative polymerization to synthesize PANI on Cotton fabric surfaces with varying dopant(HCl)concentrations.Pre-treatment using NaOH is implemented to improve the conductivity of the fabric surface by increasing the monomer absorption.This research explores the morphological and structural analysis employing SEM,FTIR and EDX.The surface resistivity was measured using a digital multimeter,and thermal stability is measured using TGA.Upon successful polymerization,a homogenous coating layer is observed.It is revealed that the simple pre-treatment technique significantly reduces the surface resistivity of Cotton fabric to 1.27 kΩ/cm with increasing acid concentration and thermal stability.The electro-thermal energy can also reach up to 38.2°C within 50 s with a deployed voltage of 15 V.The modified fabric is anticipated to be used in thermal regulation,supercapacitor,sensor,UV shielding,antimicrobial and other prospective functional applications.

Preparation and Characterization of Subsurface Silver Particulate Films on Polymer Blends of Polystyrene/Poly(2-vinylpyridine)/Poly(vinylpyrollidone)/Poly(4-vinylpyridine)

Silver particulate thin films on softened polymer blends of Polystyrene (PS)/Poly(2-vinyl pyridine) (P2VP), PS/Poly(4-vinylpyridine) (P4VP), and Poly(vinylpyrollidone) (PVP)/P4VP at a rate of 0.4 nm/s held at a temperature of 457 K in vacuum of 8 × 10-6 Torr by evaporation are deposited. These silver films were characterized by their electrical behavior, optical properties and Scanning electron microscopy (SEM). Silver films deposited on softened PS, and PVP give rise to a very high room temperature resistance approaching that of the substrate resistance due to the formation of a highly agglomerated structure. On the other hand, silver films on softened P2VP and P4VP give rise to a room temperature resistance in the range of tens to a few hundred MΩ/ which is desirable for device applications. Silver films on the composites of PS/P2VP, PS/P4VP and PVP/P4VP show resistances at room temperature. The optical and plasmonic response of Ag nanoparticles onto thin layers of blends shows encapsulation of nanoparticles. The electrical properties and SEM of silver nanoparticles on the thin layers of polymer blends indicate the formation of much smaller, narrower dispersion and wide size distribution.

Thermo-Stamping Process of Glass and Carbon-Fibre Reinforced Polymer Composites

In this work, manufacturing tools for thermoplastic (TP) composites have been developed. The chosen process involves the stacking alternately of oriented dry fabrics and TP films and does not use semi-products in order to reduce material costs. This study was specifically directed towards optimizing the impregnation of continuous glass and carbon fibres reinforcing two TP amorphous matrices, the polyphenylsulfone (PPSU) and polyetherimide (PEI), to obtain semi-finished products employed for aeronautical structures. The impregnation quality of inter and intra-yarns is analyzed and validated by optical and scanning micrographic observations conducted with an optical and a Scanning Electron Microscopies (SEM), respectively. The study showed that besides the process parameters and porosity distribution in the core of warp yarns, the impregnation quality depends on the surface properties of constituents. Desizing treatment has been carried out to improve the wettability of fibres by the TP matrices.

Preparation and Characterization of Polymer Nanocomposites

The polymer nanocomposites have been the exponentially growing field of research for developing the materials in last few decades. The remarkable improvement in the polymer nanocomposite is found when a small amount of nanosized particles are added to a polymer matrix. The addition of inorganic solid nanoparticles (typically in the form of fibres, flakes, spheres or fine particles) into polymer matrix increases their physical, structural and mechanical properties. Since the polymer-nano composites have been the staple of modern polymer industry, their durability under various environmental conditions and degradability after their service life are also essential fields of research. This leads to focus on preparation & characterization of polymer nanocomposite. This article is intended to review the status of worldwide research in this aspect. The successful application of nano particles depends upon both the correct preparation techniques followed by testing through characterization. Surface modification can improve the inherent characteristics of the nano particles and serve to prepare nano composites inexistent in nature. Therefore, some tools as their various properties like electrical, optical and morphological can be used to optimize the preparation of polymer nano composites. This chapter will make an overview about different routes to prepare polymer-based nano composites by extrusion, synthesis of nano particles by sol-gel reactions, sputtering and mainly by physical evaporation deposition method.

纸板的老化状态对其PDC特性影响的实验研究

为研究纸板劣化对其极化去极化电流(polarization and depolarization currents,PDC)特性的影响,在实验室内对油浸变压器绝缘纸板进行加速热老化,在不同老化阶段取出纸板试品,对不同老化状态的纸板进行石油醚萃取变压器油和真空干燥处理。为了表征绝缘纸板的老化状态,对各老化阶段的纸板采用粘度法测量聚合度,并使用扫描电子显微镜(scanning electron microscope,SEM)观察纤维素表面的微观结构及破坏状况。在同一温度下,对干燥后不同老化状态的纸板分别进行真空中和新变压器油浸渍条件下的PDC测量。结果表明,随着老化时间的延长,纸板聚合度下降,纤维表面微观结构破坏明显。纸板劣化造成真空中和油浸渍的纸板极化去极化电流显著增大,电导率增加,并导致其绝缘电阻降低,吸收比减小。因此,对于油纸绝缘,除老化产生的水分外,纸板劣化本身也将导致纸板电导率的增大,并显著影响其极化去极化电流的测量结果。

复合絮凝剂聚合硫酸铝铁的制备及性能研究

采用广西某地的高铁铝土矿为原料,在一定的温度下加入硫酸酸溶并加入一定量的碱化剂M经水解聚合、静置熟化制备复合絮凝剂固体聚合硫酸铝铁(PAFS)。研究了硫酸用量与原料的配比、硫酸浓度、反应时间、反应温度等因素对制备产品的影响,进而进行正交设计实验,确定了制备固体聚合硫酸铝铁的最佳工艺条件。产品的氧化铁含量为5.59%,氧化铝含量为6.65%,盐基度为57.35%。对浊度为大于2000NTU的暴雨时洪水的除浊率达99.74%;通过扫描电镜和X-射线衍射对PAFS的表面结构和主要晶相组成进行分析,其形貌为大分子网状结构,主要以铁的水解高聚物和单体铝及铝的低聚物为主;通过Ferron逐时络合比色法的研究发现,该絮凝剂产品的[Al+Fe]a含量占66.72%、[Al+Fe]b占20.48%、[Al+Fe]c占12.80%。

沉淀聚合制备聚二乙烯基苯微粒

利用沉淀聚合方法，自由基引发二乙烯基苯聚合，制备了具有较窄粒度分布的聚二乙烯基苯超细微粒，用扫描电镜对其表面形态和粒度进行了表征；红外光谱表明这种聚合物超微粒仍存在有较多未反应的悬吊双键，可以继续与其它功能基团进一步反应，且粒度均一可控。

苯胺的等离子体聚合薄膜特性研究

采用苯胺的等离子体聚合法，得到致密度高、化学稳定性好的自支撑膜。ＩＲ光谱和导电性研究表明，它与化学法聚合得到的聚苯胺有明显不同的结构和特性，而且研究结果提示用此方法可得到中红外区的红外吸收材料。鉴于等离子体聚合产物大多是非结晶的无定形结构，我们通过ＳＥＭ和ＨＥＥＤ研究发现，该聚合产物有单晶存在，这对等离子体聚合的理论和实验研究有着积极的意义。

Fe_3O_4@SiO_2/P(MA-AM)复合微球调剖剂的制备及性能研究

采用共沉淀法制得纳米Fe_3O_4粒子,SiO_2包覆处理后用KH-570对其进行表面改性,后采用分散聚合法制得Fe_3O_4@SiO_2/P(MA-AM)聚合物复合微球。通过红外光谱、电镜扫描、激光粒度分析等手段对微球的Fe_3O_4@SiO_2内核和P(MAAM)聚合物外壳的复合结构进行了表征。通过对聚合物复合微球溶胀性能、封堵性能的试验表明,该微球具有良好的吸水膨胀性、耐温抗盐性以及一定的封堵运移能力,可以用于注水井的深度调剖;同时,在用于注水井调剖驱油剂使用时,若被挤入油层随采出液携带出时,也可采用磁性分离处理,是具有应用潜力的磁性调剖堵水剂。

原位聚合法制备聚苯胺纳米材料及其性能研究

采用溶液法制备纳米聚苯胺(PANI),通过液相沉淀法制备MnO2,然后通过原位聚合法制备出PANI/MnO2复合材料,再采用XRD、红外光谱、SEM测试方法表征PANI、MnO2和PANI/MnO2的微观结构及其外貌形式,结合循环伏安法、恒电流充放电以及交流阻抗法表征PANI/MnO2的电学性能。通过实证分析发现,MnO2结构呈现出不规则特征,具有γ-MnO2的特性。当完成PANI的复位过程,PANI中的MnO2开始均匀分散。PANI/MnO2复合材料比容量在MnO2和苯胺单体摩尔比为1∶5.5时最大,比容量在电流密度1.5A/g时为483.50F/g,具有良好的循环稳定性,在充放电1005次后,PANI/MnO2的容量保留了初始容量的75.43%。

PCR-g-MMA胶粘剂的制备及粘接性能

用乳液接枝聚合法合成了氯丁橡胶（OR）／甲基丙烯酸甲酯（MMA）接枝共聚物OR-g-MMA乳液;用凝聚法制备了粉末状PCR-g-MMA干胶，将其溶于甲苯中制备了胶粘剂。研究了CR／MMA接枝聚合反应条件对单体转化率的影响和PCR-g-MMA粒子在溶剂中的溶解速率及其胶粘剂的粘接性能。结果表明，在适宜的反应条件下，接枝体系的单体转化率接近100％。SEM分析表明．PCR-g-MMA粒子表面及内部存在许多宏观及微观孔洞，使产物易于洗涤、脱水和干燥．在溶剂中有极高的溶解速率．完全溶解时间为0．5～1h。仅为片状CR248完全溶解所需时间的1／10。PCR—g—MMA胶粘剂的粘接性能与CR／MMA乳液接枝聚合反应条件有关。用其粘合PVC人造革．其初粘力为20．4N／2．5cm，剥离强度为55N／2．5cm，与片状CR248／MMA溶液接枝制备所得的胶粘剂处于相同水平。

单分散聚合法制备聚苯乙烯微球

采用苯乙烯(St)为单体,偶氮二异丁腈(AIBN)为引发剂,聚乙烯基吡咯烷酮(PVP)为分散剂,无水乙醇和去离子水混合溶液作为分散介质,单分散聚合法制备聚苯乙烯微球并对聚合过程影响因素进行了探索,找出了最佳聚合条件,分别是单体浓度为45-50wt.%,AIBN浓度为3wt.%,分散剂PVP浓度1.5～2wt.%,分散介质醇水比为10:1,反应温度为95℃,反应时间为12h,在此条件下获得的微球单分散性好、粒径分布窄,平均粒径为5μm且占合成微球质量比为95%以上的聚苯乙烯微球。通过对反应产物洗涤前后的SEM电镜对比分析,进一步证明了分散剂PVP在反应过程中是以物理吸附的形式吸附在微球表面。

纤维基抗水材料的制备

以苯乙烯、甲基丙烯酸甲酯和丙烯酸丁酯作为单体,在不同单体配比条件下,用核壳乳液聚合法合成了4种丙烯酸乳液。将制得的丙烯酸乳液分别同浆渣经共同分散、涂膜、干燥,制得4种纤维基抗水材料。通过对其Cobb值进行测定,研究了材料的抗水性。结果表明,在丙烯酸乳液与浆渣有效质量比为2∶1时,4种材料的最小Cobb值分别为5.0、9.8、19.2、7.1 g/m2。用单体质量比为1∶1∶2的乳液制备出的材料抗水性最稳定。并用扫描电子显微镜(SEM)对材料的表面形态结构进行了观察。

合成电势对Li／聚吡咯正极性能的影响

为了简便真实的分析聚合电势对叫聚吡咯电池正极电化学行为的影响，同时寻找最佳聚合电势，在pt微盘电极上用恒电位法合成聚吡咯（PPy），通过循环伏安，计时电势方法对电化学行为进行检测，结果表明：当聚合区间为3．8-4．2V（VSLi／Li^＋）时，PPy膜电极均具有较好的可遗陛和电化学容量。选择4．0V（VS Li／Li^＋）电位聚合，PPy微电极的电化学陛能更佳。通过SEM测试技术进一步分析表明，不同电位直接影响聚吡咯的形貌，这是导致电池可逆性不同的直接原因；选择4．0V电势进行聚合，可以得到满足二次电池充放电性能要求的PPy膜电极。

Synthesis and Characterization of Polypyrrole (PPy) Thin Films

Polypyrrole (PPy) was synthesized by chemical oxidative polymerization technique using monomer pyrrole and ammo-nium persulphate as an oxidant in a ratio of 1:1. Thin films of polypyrrole were prepared by dissolving polypyrrole in mcresol and cast using spin coating technique on glass substrates. Thin films of polypyrrole were characterized by X ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infra red spectroscopy (FTIR), UV visible spectroscopy and electrical resistivity by four probe method. The XRD spectra showed that the polypyrrole is amorphous in nature. SEM studies revealed a uniform granular structure of PPy. The FTIR spectra shows that the presence of all characteristics absorption peaks of polypyrrole that is, 890 cm?1 (=C–H out-of-plane vibration), 1040 cm?1 (=C–H in-plane vibration), 1170 cm?1 (N–C stretch bending) and 1410 cm?1 (pyrrole ring vibration). UV visible study shows PPy films exhibit absorption peak at 446 nm (2.77 eV). Room temperature electrical resistivity of PPy is in the critical regime of the metal –to –insulator (M-I) transition.

Inter laminar shear strength behavior of acid,base and silane treated E-glass fibre epoxy resin composites on drilling process

In this present work siliconized e-glass fibre reinforced epoxy resin composite has been prepared and compared with acid and base treated e-glass fibre epoxy composites to know the significant advantage of silane treatment on fibre. The composites were fabricated by laying 20, 30 and 40vol% of e-glass fibre into epoxy resin matrix. The e-glass fibre woven mat was surface treated by an amine functional coupling agent 3-Aminopropyletrimethoxysilane(APTMS). The fibres were surface treated by aqueous solution method and thermo assisted to create silinol groups. Similarly for acid treatment H_2SO_4 and base treatment Na OH with 1N concentration was used for surface treating the fibres. Effectiveness of silane treatment on glass fibre was compared by inter laminar shear strength test according to ASTM D 2344.Drilling process with varying diameter drill bit and varying cutting speed was applied to check the composites for their delamination resistance while machining. Maximum improvement of 15%, 12.5% and9%(20, 30 and 40 vol %) on ILSS was achieved for siliconized e-glass fibre reinforced epoxy composites.The scanning electron microscopy images revealed that no fibre pull out was present on fractured surfaces of composites which contains siliconized e-glass fibre. Similarly better dimensional accuracy was achieved on drilling process for composites contains siliconized e-glass fibre.

Electrochemical polymerization of 2,6-pyridinediamine and characterization of the resulting polymer

Electrochemical synthesis of poly（2,6-pyridinediamine） （PPa） in aqueous sodium hydroxide solution has been carried out by using cyclic voltammetry for the first time. The scanning electron microscopy （SEM） revealed the interpenetrating network structure of the as-prepared PPa film, which makes it possible that anions can be doped into the polymer in the oxidation process, and vice versa in the reduction process. The results from FT-IR spectrum provided a possible polymerization mechanism of 2,6- pyridinediamine.

飞秒激光双光子聚合构建水溶性石墨烯-光刻胶的3D微结构

通过将水溶性石墨烯掺入至光引发剂2-苄基-2-二甲基氨基-1-(4-吗啉苯基)丁酮和季戊四醇三丙烯酸酯混合而成的光刻胶中,利用飞秒激光双光子聚合技术制作一系列平面图案及三维立体结构。利用亲水角测试表征混合物的浸润性,激光透过深度测试表征混合物的穿透性。实验结果证明,掺杂有水溶性石墨烯的混合液与玻璃仍具有较强结合力和一定激光穿透性。最后利用拉曼成像与扫描电子显微镜表征平面图案及三维结构。证实使用去离子水作为分散液可以将水溶性石墨烯掺杂进微结构中,并且掺杂有水溶性石墨烯的微结构在机械性能上比纯光刻胶微结构,结构更稳定且形貌更统一。

Morphological, Rheological and Mechanical Properties of Pla-Typha Based Biocomposites

Due to the demand from society for the consumption of ecological polymeric materials, one of the polymers that have satisfied this request is the poly (lactic acid) (PLA). This polymer is derived from renewable resources, it is recyclable and biodegradable. It presents a good understanding between the promising properties and the cost. However, a route to increase the mechanical properties and reduce the cost of PLA is the elaboration of PLA based biocomposites by using fillers from natural waste. In this work, The effect of Typha content on the morphological, rheological, thermal and mechanical properties of PLA matrix was studied. Four formulations were produced with different mass concentrations. The results showed an increase in the viscoelastic properties, as a function of the Typha stem powder concentration. The DSC analysis showed an increase in the crystallinity rate of the various composites confirming the nucleating effect provided by the filler. TGA analysis indicated a decrease in the decomposition temperature of the composites. Mechanical tensile tests have shown a significant improvement in the mechanical properties mainly for the samples containing 45% (w/w) of Typha powder.

Microbial analysis and surface characterization of SABIC carbon steel corrosion in soils of different moisture levels

We tested the effect of three types of soil inSaudi Arabiaon SABIC carbon steel grade X60 (SCSX60) specimens. The results showed that the environment effect of different condition was very clear, indicating that the studied soils were very corrosive SCSX60 specimens. The composition and morphology of corrosion were different in the tested soil based on moisture content and immersion period. In addition, the results showed that bacteria play an important role in the corrosion of SCSX60. The morphologies of corrosion products were analyzed using scanning electron microscopy to further elucidate the complex systems found in the studied soil.