scholarly journals Nanopatterned Polymer Molds Using Anodized Aluminum Templates for Anti-Reflective Coatings

Polymers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 3333
Author(s):  
Soon Hyuk Lim ◽  
Nguyễn Hoàng Ly ◽  
Jung A. Lee ◽  
Ji Eun Kim ◽  
Se-Woong La ◽  
...  
Keyword(s):  
Anodized Aluminum ◽  
Sem Images ◽  
Uv Curable ◽  
Transparent Films ◽  
Reflective Coating ◽  
Transparent Coating ◽  
Acrylate Resin ◽  
Reflective Coatings ◽  
Physical Degradation ◽  
Pet Substrate

This work introduces a facile geometry-controlled method for the fabrication of embossed and engraved polymeric moth-eye-inspired nanostructures in imprinting molds using anodic aluminum oxide (AAO) templates, resulting in a novel anti-reflective transparent coating. The moth-eye nanostructures are prepared directly on the surface of a flexible polyethylene terephthalate (PET) substrate. As a prerequisite procedure, a UV-curable polyurethane acrylate resin is spun on the PET. The shape of the moth-eye nanostructures can then be adjusted by controlling the size and shape of the nanopores in the AAO templates. Both embossed and concaved polymer moth-eye nanostructures were successfully mounted on a PET substrate. Embossed polymer replica molds were prepared using the AAO master templates in combination with an imprinting process. As revealed by field-emission electron microscope (FE-SEM) images, conical nanopatterns in the AAO template with a diameter of ~90 nm and a depth of ~100 nm, create a homogeneous embossed morphology in the polymer moth-eye nanostructure. The polymeric molds with the depths of 300 and 500 nm revealed the amalgamated structures in their apexes. In addition, a dip-imprinting process of the polymeric layers was implemented to yield a concaved mold by assembly on the surface of the 100 nm embossed polymer mold substrate. Considering that the embossed structures may be crumbled due to their protuberant shapes, the concaved geometries can have an advantage of stability in a certain application concerning physical degradation along with a higher transmission by ~2%, despite somewhat nonuniform structure. The experimental and theoretical results of this study indicate that this polymer layer has the potential for use in anti-reflective coating applications in transparent films.

In vivo and in vitro testing of gloves for protection against UV-curable acrylate resin systems

1984 ◽  
Vol 11 (5) ◽  
pp. 279-282 ◽  
Author(s):  
Robert L. Rietschel ◽  
Ronald Muggins ◽  
Nicole Levy ◽  
Pat M. Pruitt
Keyword(s):  
In Vitro Testing ◽  
Uv Curable ◽  
Acrylate Resin

Biomimetic Crack Sensors Using Electrohydrodynamic Technology

2021 ◽  
Vol 21 (7) ◽  
pp. 3773-3778
Author(s):  
Keon-Young Kim ◽  
Se-Min Jeong ◽  
Chang-Yull Lee
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Crack Initiation ◽  
Health Monitoring ◽  
Grid Structure ◽  
Sem Images ◽  
Impact Tester ◽  
Microscopic Damage ◽  
Pet Substrate ◽  
Scanning Electron

This paper proposes a new mechanism for detecting microscopic damage of structures based on imitating the sensory organs of spiders. Therefore, it is essential to manufacture sensors that can react sensitively to the micro deformations of structures. Numerous cracks were intentionally generated to improve the sensitivity of the proposed sensor, and an increase in the gap of the crack was observed by scanning electron microscopy (SEM) observation. Electrohydrodynamic technology is used to detect deformations in a structure of depositing Ag nano paste on a polyethylene terephtha-late (PET) substrate. Ag nano lines are also observed by SEM images. The sensor is constructed as a grid structure, by forming layers patterned horizontally and vertically. An impact tester is used to verify the mechanism for structural health monitoring using the developed sensor. The resistance changes of the sensors are applied to estimate the structure’s damaged location. The intersections of the lines with varying resistance can be used to accurately detect crack initiation. The proposed mechanism is a powerful methodology for estimating and detecting microscopic deformations and damage to structures.

scholarly journals UV-Curable Hydrophobic Coatings of Functionalized Carbon Microspheres with Good Mechanical Properties and Corrosion Resistance

Coatings ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 439 ◽  
Author(s):  
Jiajia Wen ◽  
Chengchen Feng ◽  
Huijie Li ◽  
Xinghai Liu ◽  
Fuyuan Ding ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Corrosion Resistance ◽  
Thermogravimetric Analysis ◽  
Photoelectron Spectroscopy ◽  
Carbon Microspheres ◽  
Sem Images ◽  
Water Contact ◽  
Pencil Hardness ◽  
Uv Curable ◽  
Functional Product

Polyurethane acrylates (PUAs) are a kind of UV curable prepolymer with excellent comprehensive performance. However, PUAs are highly hydrophilic and when applied outdoors, presenting serious problems caused by rain such as discoloring, losing luster and blistering. Thus, it’s important to improve their hydrophobicity and resistance against corrosion. In this paper, carbon microspheres (CMSs) were modified through chemical grafting method. Active double bonds were introduced onto the surface of organic carbon microspheres (OCMSs) and the functional product was referred to as FCMS. The results of Transmission Electron Microscope (TEM), X-ray Photoelectron Spectroscopy (XPS) and Thermogravimetric analysis (TGA) showed that organic chain segments were successfully connected to the surface of OCMSs and the grafting efficiency was as high as 16%. FCMSs were successfully added into UV-curable polyurethane acrylate prepolymer to achieve a hydrophobic coating layer with good mechanical properties, thermal stability and corrosion resistance. When the addition of FCMSs were 1%, thermogravimetric analysis (TGA) results showed that 5% of the initial mass was lost at 297 °C. The water absorption decreased from 52% to 38% and the water contact angle of the PUA composite increased from 72° to 106°. The pencil hardness increased to 4H and obvious crack termination phenomenon was observed in SEM images. Moreover, the corrosion rate was decreased from 0.124 to 0.076 mm/a.

Modeling and Analysis of Organic Light Emitting Diode with Thin Film Anti-Reflective Coatings

2020 ◽  
Vol 15 (4) ◽  
pp. 425-431
Author(s):  
B. M. Chaya ◽  
Prasant Kumar Pattnaik ◽  
K. Narayan
Keyword(s):  
Power Efficiency ◽  
Light Emitting Diode ◽  
Fdtd Method ◽  
Light Output ◽  
Single Layer ◽  
Light Emitting ◽  
Organic Light Emitting Diode ◽  
Reflective Coating ◽  
Organic Light ◽  
Reflective Coatings

The effects of anti-reflective coatings (ARC) on organic light emitting diode (OLED) optical characteristics are reported in this paper. The light output produced from the OLED is not 100%. But the emitted light is trapped due to various Modes. The losses at the glass air substrate interfaces of an OLED are addressed in this work. The Anti-Reflective coatings increase the light output by reducing OLED reflections at the interface between glass and air. The Finite Difference Time Domain (FDTD) method and the Fresnel theory have been used to design the device and study the effects on OLED of the Single Layer Anti-Reflective Coating (SLAR) and Double Layer Anti-Reflective Coating (DLAR). The thicknesses and refractive indices of the layers of the anti-reflective coatings were optimized. We also compared the light out coupling power efficiency of the SLAR coated OLED with that of an OLED with a DLAR coating and also with Conventional OLED. The results show that the enhancement in light output efficiency of the DLAR coated OLED was slightly higher than that of the SLAR coated OLED.

scholarly journals Ultra-low threshold lasing through phase front engineering via a metallic circular aperture

2022 ◽  
Vol 13 (1) ◽  
Author(s):  
Zhixin Wang ◽  
Filippos Kapsalidis ◽  
Ruijun Wang ◽  
Mattias Beck ◽  
Jérôme Faist
Keyword(s):  
Semiconductor Lasers ◽  
Continuous Wave ◽  
Threshold Power ◽  
Circular Aperture ◽  
Phase Front ◽  
Reflective Coating ◽  
Low Threshold ◽  
Ridge Lasers ◽  
Reflective Coatings ◽  
Electrical Consumption

AbstractSemiconductor lasers with extremely low threshold power require a combination of small volume active region with high-quality-factor cavities. For ridge lasers with highly reflective coatings, an ultra-low threshold demands significantly suppressing the diffraction loss at the facets of the laser. Here, we demonstrate that introducing a subwavelength aperture in the metallic highly reflective coating of a laser can correct the phase front, thereby counter-intuitively enhancing both its modal reflectivity and transmissivity at the same time. Theoretical and experimental results manifest a decreasing in the mirror loss by over 40% and an increasing in the transmissivity by 104. Implementing this method on a small-cavity quantum cascade laser, room-temperature continuous-wave lasing operation at 4.5 μm wavelength with an electrical consumption power of only 143 mW is achieved. Our work suggests possibilities for future portable applications and can be implemented in a broad range of optoelectronic systems.

Unventilated Air Layers with a Reflective Coating in the Building Envelope

2018 ◽  
Vol 931 ◽  
pp. 496-501 ◽  
Author(s):  
Nina P. Umnyakova ◽  
Adam Ujma
Keyword(s):  
Heat Exchange ◽  
Thermal Insulation ◽  
Building Envelope ◽  
Radiative Heat Exchange ◽  
Aluminium Foil ◽  
Reflective Coating ◽  
Air Layers ◽  
Design Calculations ◽  
Reflective Coatings

Heat exchange through infrared radiation in air layers located inside building envelopes may be significantly modified in case of use of aluminium foil coatings therein. The intensity of conductive, convective and radiative heat exchange in these structures depends on the thickness of the air layer and the temperature difference on its surfaces. Generally speaking, application of aluminium foil in air layers of a building envelope improves its thermal insulation capacity. However, assessment of efficiency of such a solution and determination of the thermal resistance value of a given structure is often incorrectly determined and assumed for design calculations. The article analyzes the instructions and principles of determination of thermal insulation capacity of unventilated air layers. Provisions of two standards have been compared with results of tests of air layer parameters. The effect of different factors on heat exchange and insulation capacity of air layers with reflective coatings has been considered and assessed.

Thermotropic overheating protection glazings: effect of functional additives and processing conditions on the overheating protection performance

2014 ◽  
Vol 34 (2) ◽  
pp. 161-172
Author(s):  
Andreas Weber ◽  
Katharina Resch
Keyword(s):  
Nucleating Agent ◽  
Nucleating Agents ◽  
Processing Conditions ◽  
Material Constitution ◽  
Uv Curable ◽  
Temperature Conditions ◽  
Functional Additives ◽  
Annealing Step ◽  
Acrylate Resin

Abstract Within this study, the effect of functional additives and processing conditions on the overheating protection performance of thermotropic systems with fixed domains (TSFD) for overheating protection purposes was evaluated. The focus was on improving the overheating protection performance of a prototype TSFD based on a UV curable acrylate resin by optimization of the material constitution (addition of functional additives like surfactants and nucleating agents) and the processing conditions (temperature conditions during manufacturing, annealing). For the evaluated system, an effect of the nucleating agent on the overheating protection performance was ascertained. Furthermore, omission of an annealing step improved the overheating protection performance slightly.

Fabrication of Anti-Reflective Coatings on Solar Collector Tubes

2011 ◽  
Vol 306-307 ◽  
pp. 125-129 ◽  
Author(s):  
Yu Chao Niu ◽  
Guo Wei Huang ◽  
Ying Chen ◽  
Wen Wen Dou ◽  
De Ming Sun ◽  
...  
Keyword(s):  
Solar Collector ◽  
Sol Gel ◽  
Scratch Resistance ◽  
Scanning Microscope ◽  
Acid Base ◽  
Pencil Hardness ◽  
Reflective Coating ◽  
Atomic Force ◽  
Relative Standard ◽  
Reflective Coatings

In order to reduce the reflection of solar collector cover tube and improve its transmissivity, a kind of SiO2anti-reflective coating on the cover tube was prepared using acid-base two-step sol-gel method. The surface morphology of the anti-reflective coating was observed using atomic force microscope and electronic scanning microscope. The scratch resistance of the coating was tested using pencil hardness apparatus. The transmissivity and anti-impact properties of the cover tube coated with the coating were measured respectively by means of the spectrophotometer and the relative standard method. The results showed that the anti-reflective coating possesses a higher scratch resistance and the coated cover tube has good transmissivity and anti-impact.

Sign in / Sign up

Export Citation Format

Share Document