Effect of Modified Silica Materials on Polyvinyl Chloride (PVC) Substrates to Obtain Transparent and Hydrophobic Hybrid Coatings

In this research, we report a simple and inexpensive way to prepare transparent and hydrophobic hybrid coatings through deposition of different silica materials on polyvinyl chloride (PVC) substrates. The silica materials were prepared using an acid-catalyzed sol–gel method at room temperature (25 ± 2 °C), using alkoxysilanes: tetraethoxysilane (TEOS), as the silica source, and ethoxydimethylvinylsilane (DMVES), triethoxyoctylsilane (OTES), and trimethoxyhexadecylsilane (HDTMES), as modifier agents. The obtained materials were characterized (either as powders or as thin films) by Fourier-transform infrared spectroscopy (FTIR), UV/Vis spectroscopy, transmission electron microscopy (TEM), thermogravimetric analysis (TGA), atomic force microscopy (AFM), spectroscopic ellipsometry (SE), and water contact-angle measurements. UV/Vis spectra showed that the PVC substrate coated with the silica material containing TEOS/DMVES/OTES had a transmittance of about 90% in the wavelength range of 650–780 nm. The water contact angles increased from 83° for uncoated PVC substrate to ~94° for PVC substrates coated with the sol–gel silica materials. These PVC films with hybrid silica coatings can be used as the materials for outdoor applications, such as energy-generating solar panel window blinds or PVC clear Windmaster outdoor blinds.

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Preparation and Characterization of Some Sol-Gel Modified Silica Coatings Deposited on Polyvinyl Chloride (PVC) Substrates

Coatings ◽

10.3390/coatings11010011 ◽

2020 ◽

Vol 11 (1) ◽

pp. 11

Author(s):

Violeta Purcar ◽

Valentin Rădițoiu ◽

Alina Rădițoiu ◽

Raluca Manea ◽

Florentina Monica Raduly ◽

...

Keyword(s):

Polyvinyl Chloride ◽

Fourier Transforms ◽

Sol Gel ◽

Gravimetric Analysis ◽

Antireflective Coatings ◽

Modified Silica ◽

Silica Coatings ◽

Static Contact ◽

Vis Spectroscopy ◽

Silica Materials

Transparent and antireflective coatings were prepared by deposition of modified silica materials onto polyvinyl chloride (PVC) substrates. These materials were obtained by the sol-gel route in acidic medium, at room temperature (25 °C), using different alkoxysilanes with various functional groups (methyl, vinyl, octyl or hexadecyl). Physicochemical and microstructural properties of resulted silica materials and of thin coatings were investigated through Fourier Transforms Infrared Spectroscopy (FTIR), UV-Vis spectroscopy, Thermal Gravimetric Analysis (TGA), Dynamic Mechanical Analysis (DMA), Atomic Force Microscopy (AFM) and ellipsometric measurements. Wetting behaviors of the silica coatings were evaluated by measurement of static contact angle against water. FTIR spectra of materials confirmed the high degree of cross-linking that result from the formation of the inorganic backbone through the hydrolysis and polycondensation reactions together with the formation of the organic network. These sol-gel silica coatings showed a reduction in the reflectance (10%) compared with uncoated PVC substrate. AFM reveals that the films are uniform, and adherent to the substrate, but their morphology is strongly influenced by the chemical composition of the coating matrices. These silica coatings can be useful for potential electronic and optical devices.

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Synthesis and Characterization of ZnO-SiO2/Epoxy Nanocomposite Coating by Sol-Gel Process

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.16.1 ◽

2012 ◽

Vol 16 ◽

pp. 1-7

Author(s):

Nazanin Farhadyar ◽

Mirabdullah Seyed Sadjadi

Keyword(s):

Polyethylene Glycol ◽

Sol Gel ◽

Nanocomposite Coating ◽

Contact Angles ◽

Hybrid Coatings ◽

Coating Film ◽

Water Contact ◽

Unit Form ◽

Hybrid Solution ◽

Sol Gel Process

In this paper, we report preparation of hydrophilic hybrid nanocomposite coatings on glass substrates using Zinc acetate solutions based on 3-glycidoxypropyltrimethoxysilane (GPTMS), epoxy resin, aromatic amine (HY850), polyethylene glycol (PEG) and surfactant (polyoxyethylene(4)laurylether) by the sol-gel process. Furthermore, the effects of PEG addition to the precursor solutions on the hydrophilic property and microstructure of the resultant coating film were studied. The hydrophilic behavior study of the synthesized hybrid was performed by adding different amounts of polyethylene glycol precursor to the hybrid solution. Experimental results show that, among different amounts of PEGs, the best results are obtained by addition of PEGs (400) to the hybrid solution which can decrease the water contact angles down to 16 and using surfactant down to 0, and increase the free surface energy. Coated glass exhibits a higher strength than uncoated glass. Attenuated total reflectance infrared spectroscopic (ATR-IR) technique was used to characterize the structure of the hybrid films. The chemical structure of obtained network affects morphology of the coating. The morphology of the hybrid coatings was examined by transmission electron microscopy (TEM). The hybrid systems have a unit form structure and the inorganic phases were in the nanosize scale,

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Preparation of TiO2–SiO2 Hybrid Nanosols Coated Flame-Retardant Polyester Fabric Possessing Dual Contradictory Characteristics of Superhydrophobicity and Self Cleaning Ability

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17166 ◽

2020 ◽

Vol 20 (3) ◽

pp. 1780-1789 ◽

Cited By ~ 5

Author(s):

Priyanka Katiyar ◽

Shraddha Mishra ◽

Anurag Srivastava ◽

N. Eswara Prasad

Keyword(s):

Electron Microscopy ◽

Contact Angle ◽

Flame Retardant ◽

Protective Clothing ◽

Sol Gel ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Water Contact ◽

Vis Spectroscopy ◽

Self Cleaning

TiO2, SiO2 and their hybrid nanocoatings are prepared on inherent flame retardant textile substrates from titanium(IV)iso-proproxide (TTIP) and tetraethoxysilane (TEOS) precursors using a sol–gel process followed by hydrothermal treatment. The coated samples are further functionalized by hexadecyltrimethoxysilane (HDTMS) to impart superhydrophobicity. Sample characterization of the nanosols, nanoparticles and coated samples are investigated using, X-ray diffractometer, transmission electron microscopy, scanning electron microscopy, UV-Vis spectroscopy, contact angle measurement. Stain degradation test under mild UV irradiation shows almost 54% degradation of coffee stain within 4 hours measured by Spectrophotometer. UV-Vis Absorption Spectroscopy demonstrates complete degradation of methyl orange colorant within 3 hours. Hybrid nanosol coated and HDTMS modified inherent flame retardant polyester surfaces show apparent water contact angle as ~145°, which is much closer to proximity of superhydrophobic surfaces. Thus, the novelty of present work is, by using sol–gel technique, a bi-functional textile surface has been developed which qualifies the very specific requirements of protective clothing like self-cleaning property (imparted by TiO2 nanoparticles) and superhydrophobicity (imparted by SiO2 nanoparticles and further surface modification by HDTMS), which are entirely contradictory in nature, in a single fabric itself. Thus developed textile surfaces also possess the other attributes of protective clothing like flame retardancy and air permeability.

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Preparation of TiO2 Thin Films and its Superhydrophilic Properties

Materials Science Forum ◽

10.4028/www.scientific.net/msf.620-622.695 ◽

2009 ◽

Vol 620-622 ◽

pp. 695-698

Author(s):

Jing Ma ◽

Wen Xiu Liu ◽

Xiao Guang Qu ◽

Dan Ni Yu ◽

Wen Bin Cao

Keyword(s):

Thin Film ◽

Tio2 Thin Film ◽

Annealing Temperature ◽

Sol Gel ◽

Soda Lime ◽

Contact Angles ◽

Soda Lime Glass ◽

Water Contact ◽

Different Temperatures ◽

Hydrolysis Of

TiO2 thin film was prepared on soda lime glass by hydrolysis of Ti(OC4H9)4 in alcoholic solutions by sol-gel method combined with spin-coating and calcination different temperatures. Prepared samples were characterized by XRD, FESEM, and measurement of contact angles and transmittance. XRD identification reveals that the films are composed of anatase TiO2 when the annealing temperature was set at 450~550 oC. SiO2 layer was coated on the surface of the glass firstly to barrier the diffusing of sodium ions from the substrate. Light-induced superhydrophilicity of the TiO2 thin film has been investigated. To increase the illumination light intensity will decrease the water contact angle. The superhydrophilicity of the TiO2 thin film will disappear more slowly in the dark than that in the field of ultrasound.

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Fabrication of TiO2Nanotanks Embedded in a Nanoporous Alumina Template

Journal of Nanomaterials ◽

10.1155/2015/452148 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

C. Massard ◽

S. Pairis ◽

V. Raspal ◽

Y. Sibaud ◽

K. O. Awitor

Keyword(s):

Electron Microscopy ◽

Sol Gel ◽

Thermal Treatments ◽

X Ray Diffraction ◽

Alumina Template ◽

Nanoporous Alumina ◽

Selected Area Electron Diffraction ◽

Transmission Electron ◽

Vis Spectroscopy ◽

Sol Gel Process

The feasibility of surface nanopatterning with TiO2nanotanks embedded in a nanoporous alumina template was investigated. Self-assembled anodized aluminium oxide (AAO) template, in conjunction with sol gel process, was used to fabricate this nanocomposite object. Through hydrolysis and condensation of the titanium alkoxide, an inorganic TiO2gel was moulded within the nanopore cavities of the alumina template. The nanocomposite object underwent two thermal treatments to stabilize and crystallize the TiO2. The morphology of the nanocomposite object was characterized by Field Emission Scanning Electron Microscopy (FESEM). The TiO2nanotanks obtained have cylindrical shapes and are approximately 69 nm in diameter with a tank-to-tank distance of 26 nm. X-ray diffraction analyses performed by Transmission Electron Microscopy (TEM) with selected area electron diffraction (SAED) were used to investigate the TiO2structure. The optical properties were studied using UV-Vis spectroscopy.

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Microwave-assisted surface modification for the separation of polycarbonate from polymethylmethacrylate and polyvinyl chloride waste plastics by flotation

Waste Management & Research ◽

10.1177/0734242x16682078 ◽

2016 ◽

Vol 35 (3) ◽

pp. 294-300

Author(s):

Luoluo Huang ◽

Hui Wang ◽

Chongqing Wang ◽

Junyao Zhao ◽

Bo Zhang

Keyword(s):

Potassium Permanganate ◽

Polyvinyl Chloride ◽

Treatment Time ◽

Contact Angles ◽

Separation Process ◽

Infrared Spectrometry ◽

Waste Plastics ◽

Optimum Conditions ◽

Water Contact ◽

Microwave Assisted

Microwave-assisted potassium permanganate modification (MPPM) was used for the flotation separation of polycarbonate (PC) from polyvinyl chloride (PVC) and polymethylmethacrylate (PMMA) waste plastics. The separation process was optimized by investigating the potassium permanganate concentration, treatment time, flotation time and frother concentration. MPPM selectively reduced the flotation recovery of PC. The optimum conditions were determined to be: potassium permanganate concentration, 2 mM/L; treatment time, 1 min; frother concentration, 17.57 g/L; and flotation time, 1 min. PC was efficiently separated from PVC and PMMA under the optimum conditions. The purity of the separated PC was 97.71%. The purity and recovery of PVC and PMMA were both >95%. The modification mechanism was investigated using the water contact angles, Fourier transform infrared spectrometry and scanning electron microscopy. This work provides technical insights into the industrial recycling of waste plastics.

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Microstructure, Mössbauer, and Optical Characterizations of Nanocrystalline α-Fe2O3 Synthesized by Chemical Route

ISRN Ceramics ◽

10.5402/2011/406094 ◽

2011 ◽

Vol 2011 ◽

pp. 1-8 ◽

Cited By ~ 3

Author(s):

Abhijit Banerjee ◽

Soumitra Patra ◽

Mahuya Chakrabarti ◽

Dirtha Sanyal ◽

Mrinal Pal ◽

...

Keyword(s):

Annealing Temperature ◽

Sol Gel ◽

Rietveld Analysis ◽

Ferromagnetic Behavior ◽

Chemical Route ◽

Perfect Lattice ◽

Transmission Electron ◽

Vis Spectroscopy ◽

Type Semiconductor ◽

Crystallite Sizes

Nanocrystalline α-Fe2O3 of crystallite sizes ranging from 18 nm to 54 nm has been prepared by sol gel process and postannealing the powder up to 500C∘. X-ray diffraction and transmission electron microscopy images have been used for determining the average crystallite sizes of the prepared samples. The Rietveld analysis reveals that the “as-prepared” α-Fe2O3 powders are not completely stoichiometric, and significant (~20%) oxygen vacancies are noticed in the α-Fe2O3 lattice. Oxygen atoms in as-prepared sample are significantly displaced and the lattice is heavily distorted. With increasing annealing temperature the lattice approaches towards the stoichiometric oxygen concentration and perfect lattice configuration. Mössbauer spectrum of the unannealed (as-prepared) α-Fe2O3 sample shows the superparamagnetic behavior at room temperature whereas all annealed samples show complete ferromagnetic behavior. Optical band gaps of these nanocrystalline α-Fe2O3 samples have been measured from UV-Vis spectroscopy and found to decrease from 2.65 eV to 2.50 eV, like an n-type semiconductor, with increasing annealing temperature up to 500C∘.

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Facile Approach to Develop Hierarchical Roughness fiber@SiO2 Blocks for Superhydrophobic Paper

Materials ◽

10.3390/ma12091393 ◽

2019 ◽

Vol 12 (9) ◽

pp. 1393 ◽

Cited By ~ 5

Author(s):

Qing Wang ◽

Jieyi Xiong ◽

Guangxue Chen ◽

Ouyang Xinping ◽

Zhaohui Yu ◽

...

Keyword(s):

Large Scale ◽

Low Cost ◽

Sol Gel ◽

Sio2 Nanoparticles ◽

Contact Angles ◽

Preparation Process ◽

Water Contact ◽

Mechanical Durability ◽

Complex Preparation ◽

Superhydrophobic Paper

Papers with nanoscaled surface roughness and hydrophobically modification have been widely used in daily life. However, the relatively complex preparation process, high costs and harmful compounds have largely limited their applications. This research aims to fabricate superhydrophobic papers with low cost and nontoxic materials. The surface of cellulose fibers was initially coated with a film of SiO2 nanoparticles via sol-gel process. After papermaking and subsequent modification with hexadecyltrimethoxysilane through a simple solution-immersion process, the paper showed excellent superhydrophobic properties, with water contact angles (WCA) larger than 150°. Moreover, the prepared paper also showed superior mechanical durability against 10 times of deformation. The whole preparation process was carried out in a mild environment, with no intricate instruments or toxic chemicals, which has the potential of large-scale industrial production and application.

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THE STABILITY OF SUPERHYDROPHOBIC COTTON FABRICS PREPARED BY SOL–GEL COATING OF SiO2 AND TiO2

Surface Review and Letters ◽

10.1142/s0218625x13500649 ◽

2013 ◽

Vol 20 (06) ◽

pp. 1350064 ◽

Cited By ~ 7

Author(s):

XUE-WEI WANG ◽

CUI GUO ◽

ZHI-HAO YUAN

Keyword(s):

Uv Light ◽

Sol Gel ◽

Volume Ratio ◽

Sodium Silicate Solution ◽

Cotton Fabrics ◽

Contact Angles ◽

Light Irradiation ◽

Water Contact ◽

Uv Light Irradiation ◽

Silica And Titania

Superhydrophobic cotton fabrics are prepared using silica and titania hybrid sol and hexadecyltrimethoxysilane. The surface morphology of cotton fabrics is characterized by scanning electron microscopy. The water contact angles on the as-prepared superhydrophobic cotton fabrics is 159° when the volume ratio between sodium silicate solution and titania sol is 1:3, and the corresponding cotton fabrics can keep the contact angle of 152° after 10 cycles of home machine washing. Meanwhile the treated cotton fabrics can also keep superhydrophobicity after 60 min of UV light irradiation. These results indicate that the cotton fabrics treated with silica and titania hybrid sol and modified with hexadecyltrimethoxysilane show excellent superhydrophobic stability under washing and UV light irradiation. This paper provides the new notion and beneficial reference for the application of the superhydrophobic cotton fabrics in the future.

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Multifunctional nanocomposite transparent UV-blocking films sythesized by sol-gel process for optical, automotive and aeronautic applications

MRS Proceedings ◽

10.1557/proc-0901-ra16-30-rb16-30 ◽

2005 ◽

Vol 901 ◽

Author(s):

Phani Ratna Ayalasomayajula ◽

S. Santucci

Keyword(s):

Thin Films ◽

Contact Angle ◽

Morphological Changes ◽

Sol Gel ◽

Chemical Properties ◽

Contact Angles ◽

Nanocomposite Films ◽

Energy Materials ◽

Water Contact ◽

Uv Blocking

AbstractDevelopment of UV blocking thin films with effective cut-off features with steep edges and high transmission in the visible and IR region have been developed. The unique optical, mechanical and chemical properties of silica and ceria nanocomposites with surface functional groups making them most promising candidate for applications in opto-electronic, automotive, and aeronautic industries. On the other hand, highly hydro and oleophobic films are being actively considered in optical, automotive and aeronautic industries to increase adhesion and scratch, abrasion resistance properties. In order to fill the gap, and fulfill the requirements to meet both ends, it could be proved that morphological changes in the nanometer range influences the water contact angles and their hystersis of low energy materials. Nanocomposite films of SiO2 and CeO2 with surface functionalisation with decafluorooctly-triethoxy silane itself forms nano-hemispheres (similar to lotus leaf) at and above 100°C favoring an increase in water contact angle from 122° (25°C) to 145°(400°C). The structural, optical, and hydrophobic properties have been examined by employing X-ray diffraction, UV-visible spectroscopy, contact angle techniques, respectively. The cut-off behavior of the deposited and annealed nanocomposite thin films have been tuned by varying different amounts of CeO2 in SiO2.

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