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Characterization of a “Smart” Hybrid Varnish Electrospun Nylon Benzotriazole Copper Corrosion Protection Coating  [PDF]
C. Menchaca,I. Casta?eda,A. Soto-Quintero,R. Guardián,R. Cruz,M. A. García-Sánchez,J. Uruchurtu
International Journal of Corrosion , 2012, DOI: 10.1155/2012/925958
Abstract: This work presents the electrochemical evaluation of a proposed copper corrosion protection hybrid coating acting as a smart corrosion protection system. This consists of an alkyd varnish, painted over electrospun nylon fibers acting as a secondary diffusion barrier and also as a benzotriazole (BTAH) inhibitor nanocontainer. Submicron diameter electrospun nylon 6-6 fiber nanocontainers were prepared from a polymeric solution containing BTAH at different concentrations, and Cu samples were coated with the electrospun fibers and painted over with an alkyd varnish by the drop method. Functional groups in fibers were determined through FTIR spectroscopy. Optical and SEM microscopies were used to characterize the nanocontainer fibers. Samples were evaluated using electrochemical impedance and noise, during six weeks of immersion, in a chloride-ammonium sulfate solution. Excellent response was obtained for the smart inhibitor coating system. For long periods of immersion good corrosion protection performance was observed. The results presented demonstrate the good barrier properties of the hybrid coating, obstructing the diffusion of aggressive species, through the electrospun structure. Furthermore the nanocontainer functionality to store and liberate the corrosion inhibitor, only when it is needed, was also proved. 1. Introduction As far as metallic monuments, statues, and works of art are concerned, accounts for the vast majority of existing and cultural heritage objects. Copper and its alloys play an important role as a base metallic material used by artists and architects. A vast majority of existing and cultural heritage objects are metallic monuments, statues, and works of art. Corrosion processes is a complex phenomenon involving corrosion products or oxide film formation on copper and alloys. These products are formed by a number of brittle oxide and hydroxide surface layers, in many cases of different colors and textures, some of calcareous origin including silicates, and all of them formed over the copper oxidation patina (typically cuprite) [1–5]. Copper, commonly used in structures and sculptures, is usually covered with layers of corrosion products providing its aesthetic value and, at the same time, protecting the metallic substrate. Due to the increase in atmospheric pollution, these layers commonly dissolve when exposed to the urban environment. Polymeric materials efficiency as corrosion protection coatings for metals increases when polymeric ligands are modified using corrosion inhibitors. Nanocontainers with storage properties, liberating
Nylon/Porphyrin/Graphene Oxide Fiber Ternary Composite, Synthesis and Characterization  [PDF]
César García-Pérez, Carmina Menchaca-Campos, Miguel A. García-Sánchez, Elsa Pereyra-Laguna, Ociel Rodríguez-Pérez, Jorge Uruchurtu-Chavarín
Open Journal of Composite Materials (OJCM) , 2017, DOI: 10.4236/ojcm.2017.73009
Abstract: This research was based on the manufacture of new composite materials that offer technological possibilities in the development of new devices with greater efficiency. Electrospinning was used to form nylon 66/-tetra-(para-aminophenyl) porphyrin (H2T(p-NH2)PP)/graphene oxide (GO) composite film. Graphene oxide coatings were obtained from graphite, through mechanical exfoliation followed by calcination and ultrasonic agitation in an oxidant solution. These samples were characterized under SEM, FTIR, Raman spectroscopy, UV-vis and R-X techniques. On the other hand, H2T(p-NH2)PP was synthesized in two steps?process by the Rothemun reaction and the Adler Method and it was integrated within nylon polyamide fibers by direct addition of a hexamethylenediamine/adipoyl chloride reactant mixture. The polymerization of the nylon/H2T(p-NH2)PP species occurs in such a way that it starts or ends on the four peripherals-NH2 groups, connected and located in the same molecular plane of H2T(p-NH2)PP, forming nylon chains at the periphery of the macrocycle. The association of GO with nylon/H2T(p-NH2)PP fibers is performed
Preparation and characterization of electrospun fibers of Nylon 11
eXPRESS Polymer Letters , 2008, DOI: 10.3144/expresspolymlett.2008.65
Abstract: Nylon 11 nanofibers mats were successfully prepared by electrospinning process from formic acid solution. The scanning electron microscopy (SEM) images showed that nanofibers with uniform diameter were produced when the polymer concentration was 10% w/v, whereas ribbons were formed at a higher concentration. The crystalline structure of the nanofibers mats was investigated using X-ray diffraction (XRD) and it was found that the nanofibers mats crystallized in α form. The melt crystallized as well as solution casted films however exhibited γ form. The thermal properties of these samples were studied using differential scanning calorimetry (DSC) and it was observed that electrospun fibers showed higher crystallinity than the melt-crystallized samples. However, the crystallinity of electrospun fibers was lower than the solution-crystallized sample.
Zinc Oxide Composites of Doxorubicin in the Form of Coating, Composite Films and Gels with a High Antitumor Activity and Low Toxicity  [PDF]
Emma R. Arakelova, Stepan G. Grigoryan, Ashot M. Khachatryan, Anahit A. Mirzoian, Zoya M. Farmazyan, Susanna L. Grigoryan, Mkrtich A. Yeranosyan, Flora G. Arsenyan, Rafayel E. Muradyan, Hrachik V. Gasparyan
Natural Science (NS) , 2019, DOI: 10.4236/ns.2019.113008
Abstract: This work is devoted to the formation doxorubicin (DOX) zinc oxide composites in the form of coating (DOX + ZnO), hydrogels and composite films of DOX with polyvinyl alcohol (DOX + PVA + ZnO) by DC-magnetron deposition of ZnO nanoscale particles (ZnO NPs) on their surfaces (DOX, DOX + PVA) with higher (two times and more) antitumor activity and considerable smaller toxicity at low doses of DOX in compositions compared to the initial drug. Using the methods of spectroscopy, atomic force microscopy (AFM), scanning electron microscopy (SEM) and X-ray Powder Diffraction (XRD), the role of ZnO NPs size on the antitumor activity of doxorubicin zinc oxide compositions is shown. AFM shows presence of many ZnO NPs on the surface DOX. A comparison of the FTIR spectra of DOX and its zinc oxide compositions has shown the presence of new bands of OH valence and deformation vibrations. It is possible to assume that interaction between ZnO and DOX takes place in the form of hydrogen bond, promoting the complexes formation. It is possible that both synergic and hydrogen-bonding ZnO with DOX increase the antitumor activity.
Electrospinning and Porosity Measurements of Nylon-6/Poly(ethylene oxide) Blended Nonwovens  [PDF]
Margaret W. Frey, Ph.D.,Lei Li, Ph.D.
Journal of Engineered Fibers and Fabrics , 2007,
Abstract: A simple method was used to prepare a nonwoven fabric of intimately co-mingled Nylon-6 and Polyethylene oxide (PEO) electrospun fibers by spinning fibers onto a rotating collector. Electrospinning parameters for each polymer were independent. Fiber mixture and distribution was uniform throughout the depth of the fabric. Porosity and pore size distribution of the materials were measured before and after a washing treatment. The PEO component was removed during the washing step to create increased pore size in the remaining fabric. This study indicates a simple method to create nanofiber nonwovens of multiple dissimilar polymers and provides a strategy for controlling pore size distribution independently from fiber formation.
Electrospun nitrocellulose and nylon: Design and fabrication of novel high performance platforms for protein blotting applications
Ashley E Manis, James R Bowman, Gary L Bowlin, David G Simpson
Journal of Biological Engineering , 2007, DOI: 10.1186/1754-1611-1-2
Abstract: The electrospinning properties of nitrocellulose, charged nylon and blends of these materials are characterized.Nitrocellulose electrospun from a starting concentration of < 110 mg/ml acetone deposited as 4–8 μm diameter beads; at 110 mg/ml-to-140 mg/ml starting concentrations, this polymer deposited as 100–4000 nm diameter fibers. Nylon formed fibers when electrospun from 60–140 mg/ml HFIP, fibers ranged from 120 nm-6000 nm in diameter. Electrospun nitrocellulose exhibited superior protein retention and increased sensitivity in slot blot experiments with respect to the parent nitrocellulose material. Western immunoblot experiments using fibronectin as a model protein demonstrated that electrospun nylon exhibits increased protein binding and increased dynamic range in the chemiluminescence detection of antigens than sheets of the parent starting material. Composites of electrospun nitrocellulose and electrospun nylon exhibit high protein binding activity and provide increased sensitivity for the immuno-detection of antigens.The flexibility afforded by electrospinning process makes it possible to tailor blotting membranes to specific applications. Electrospinning has a variety of potential applications in the clinical diagnostic field of use.The art and technology of electrospinning has generated considerable interest in the field of tissue engineering. Studies describing various aspects and applications of the electrospinning process and patent filings for intellectual property concerning this rapidly evolving technology have undergone a remarkable expansion from 1995 to 2007. Relevant to the biological sciences and the tissue engineering fields, this technology can be used to process a variety of native [1-3] and synthetic polymers [4-6] into highly porous tissue engineering scaffolds composed of nano-scale to micron-scale diameter fibers [7], a size-scale that approaches the fiber diameters observed in the native extracellular matrix.The physical, biochemical, and
In situ Polymerization of Multi-Walled Carbon Nanotube/Nylon-6 Nanocomposites and Their Electrospun Nanofibers  [cached]
Saeed Khalid,Park Soo-Young,Haider Sajjad,Baek Jong-Beom
Nanoscale Research Letters , 2008,
Abstract: Multiwalled carbon nanotube/nylon-6 nanocomposites (MWNT/nylon-6) were prepared by in situ polymerization, whereby functionalized MWNTs (F-MWNTs) and pristine MWNTs (P-MWNTs) were used as reinforcing materials. The F-MWNTs were functionalized by Friedel-Crafts acylation, which introduced aromatic amine (COC6H4-NH2) groups onto the side wall. Scanning electron microscopy (SEM) images obtained from the fractured surfaces of the nanocomposites showed that the F-MWNTs in the nylon-6 matrix were well dispersed as compared to those of the P-MWNTs. Both nanocomposites could be electrospun into nanofibers in which the MWNTs were embedded and oriented along the nanofiber axis, as confirmed by transmission electron microscopy. The specific strength and modulus of the MWNTs-reinforced nanofibers increased as compared to those of the neat nylon-6 nanofibers. The crystal structure of the nylon-6 in the MWNT/nylon-6 nanofibers was mostly γ-phase, although that of the MWNT/nylon-6 films, which were prepared by hot-pressing the pellets between two aluminum plates and then quenching them in icy water, was mostly α-phase, indicating that the shear force during electrospinning might favor the γ-phase, similarly to the conventional fiber spinning.
纳米ZnO-氧化石墨烯及ZnO-氧化石墨烯/水性聚氨酯复合涂层的抗菌性能
Antibacterial properties of nano ZnO-graphene oxide and ZnO-graphene oxide/waterborne polyurethane composite coating
 [PDF]

姜国飞,李旭飞,刘芳,赵朝成,王永强,刘春爽
- , 2018, DOI: 10.13801/j.cnki.fhclxb.20171013.002
Abstract: 循环冷却水系统滋生细菌会导致生物黏泥产生及设备腐蚀,为解决这一问题,由硅烷偶联剂γ-氨丙基三乙氧基硅烷(KH550)改性纳米ZnO,改性纳米ZnO与氧化石墨烯(GO)在二甲基乙酰胺中复合,获得纳米ZnO-GO复合抗菌材料,并利用纳米ZnO-GO改性水性聚氨酯(PU),得到纳米ZnO-GO/PU复合涂层。对纳米ZnO-GO复合抗菌材料进行表征分析及抗菌性能测试,对纳米ZnO-GO/PU复合涂层进行抗菌性能测试及物理性能分析。结果表明,纳米ZnO成功负载在GO表面,纳米ZnO-GO纯度较高,当GO质量分数为35wt%、纳米ZnO-GO使用量为160 mgL-1时,其抗菌率可达97.16%;当纳米ZnO-GO质量分数为2.33wt%时,纳米ZnO-GO/PU复合涂层抗菌率可达90.29%,同时拥有4 H的铅笔硬度及93.26%的缓蚀性能。 Microorganism growth can result in biofouling formation and equipment corrosion. In order to solve the biofouling and corrosion problems in recirculating cooling water system, nano ZnO was modified by the silence coupling agent γ-aminopropyltriethoxysilane(KH550). The modified nano ZnO and graphene oxide(GO) were compounded in the dimethylacetamide, and the nano ZnO-GO antibacterial composites were obtained. The waterborne polyurethane(PU) was modified by nano ZnO-GO to get nano ZnO-GO/PU coating composites. The characterizations and antibacterial properties of nano ZnO-GO and the antibacterial properties and physical properties of nano ZnO-GO/PU coating composites were tested and analyzed. The results show that nano ZnO is successfully supported on the surface of GO, and the purity of nano ZnO-GO is high. When the mass fraction of GO is 35wt% and the dosage of nano ZnO-GO is 160 mgL-1, the antibacterial rate of nano ZnO-GO is 97.16%. When the mass fraction of nano ZnO-GO is 2.33wt% in the coating, the antibacterial rate of nano ZnO-GO/PU composite coating is up to 90.29% and it has 4 H pencil hardness and 93.26% corrosion inhibition performance. 中国石油大学(华东)研究生创新工程(YCX2017047)
Effects on the Thermo-Mechanical and Crystallinity Properties of Nylon 6,6 Electrospun Fibres Reinforced with One Dimensional (1D) and Two Dimensional (2D) Carbon  [PDF]
Fabiola Navarro-Pardo,Gonzalo Martínez-Barrera,Ana Laura Martínez-Hernández,Víctor M. Casta?o,José Luis Rivera-Armenta,Francisco Medellín-Rodríguez,Carlos Velasco-Santos
Materials , 2013, DOI: 10.3390/ma6083494
Abstract: Electrospun one dimensional (1D) and two dimensional (2D) carbon based polymer nanocomposites are studied in order to determine the effect provided by the two differently structured nanofillers on crystallinity and thermo-mechanical properties of the nanofibres. The nanomaterials studied are pristine carbon nanotubes, oxidised carbon nanotubes, reduced graphene oxide and graphene oxide. Functional groups associated with the order structure of the polymers are analysed by infrared and Raman spectroscopies; the morphology is studied by scanning electron microscopy and the crystallinity properties are investigated by differential scanning calorimetry and X-ray diffraction. Differences in crystallisation behaviour between 1D and 2D carbon based nanofibres are shown by their crystallinity degree and their crystal sizes. The nanocomposite crystal sizes perpendicular to the plane (100) decrease with nanofiller content in all cases. The crystallinity trend and crystal sizes are in accordance with storage modulus response. The results also suggest that functionalisation favours interfacial bonding and dispersion of the nanomaterials within the polymer matrix. As a consequence the number of nucleating sites increases which in turn decreases the crystal size in the nanocomposites. These features explain the improved thermo-mechanical properties in the nanocomposites.
Characterization of a “Smart” Hybrid Varnish Electrospun Nylon Benzotriazole Copper Corrosion Protection Coating  [PDF]
C. Menchaca,I. Castañeda,A. Soto-Quintero,R. Guardián
International Journal of Corrosion , 2012, DOI: 10.1155/2012/925958
Abstract:
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