Polymer UV Research Articles

Phase signal analysis for high-sensitive temperature fiber-optic external Fabry-Perot-cavity sensor

We experimentally demonstrate a highly temperature-sensitive external Fabry-Perot cavity. The interferometric structure is composed of an air-microcavity; its fabrication uses a microcapillary and UV polymer. A temperature sensitivity close to 5.7 nm/ºC is achieved with suitable linearity (0.9896) and minimal hysteresis; a phase analysis technique is proposed and applied to overcome the trade-off between sensitivity and range of operation. This technique provides a competitive sensitivity (0.84 rad/ºC), good linearity (0.9934), and a range of operation from 25 °C to 41 °C.

Thermal properties and the decomposition path of novel UV polymers of terpene-based monomer: citronellyl methacrylate

Thermal properties and the decomposition path of more environmentally friendly polymers in both atmospheres: inert and oxidizing have been studied with a use of simultaneous TG/FTIR/QMS and DSC methods. The polymeric materials in the UV-polymerization process of cyclohexyl methacrylate and methacrylate monomer obtained from natural terpene alcohol: citronellol, using different compositions of monomers were prepared. The glass transition temperature (Tg) and thermal stability of these high solvent and chemical resistant materials were dependent on the composition and increased with increasing cyclic monomer content in the compositions. The Tg changed from 9.8˚C to 47.5˚C and a thermal stability from 195˚C to 222˚C (inert atmosphere) and from 160˚C to 217˚C (oxidizing atmosphere). The TG/FTIR/QMS analysis proved the emission of cyclohexyl methacrylate, citronellyl methacrylate and their lower molecular mass decomposition fragments, e.g., propene, cyclohexane, citronellol, citronellal, formic acid, methacrylic acid and CO, CO2 during heating of these materials in helium and air atmospheres. It indicated the same radical mechanism of their decomposition in both atmospheres which meant that the presence of oxygen did not affect the course of decomposition but reduced the initial decomposition temperature of the copolymers.

Sonochemical synthesis of lignin nanoparticles and their applications in poly (vinyl) alcohol composites

Lignin is a common and abundant byproduct of the pulp and paper industry and is generally burned to produce steam. Opportunities exist to acquire greater value from lignin by leveraging the properties of this highly conjugated biomacromolecule for applications in UV absorption and polymer reinforcement. These applications can be commercialized by producing value-added lignin nanoparticles (LNPs) using a scalable sonochemical process. In the present research, monodisperse LNPs have been synthesized by subjecting aqueous dispersions of alkali lignin to acoustic irradiation. The resulting particle size distribution and colloidal stability, as determined by dynamic light scattering, transmission electron microscopy and zeta potential analysis, of LNPs can be adjusted by varying the solution pH and ultrasonication energy. As-synthesized LNPs with a mean diameter of 204 nm were incorporated into poly (vinyl) alcohol (PVA) to prepare thin and flexible nanocomposite films using a simple solvent casting method. The addition of 2.5 wt% LNP increased the material's Sun Protection Factor up to 26 compared to 0 for neat PVA, while maintaining light transmission above 75 % in the visible spectra. In addition, the tensile strength and elastic modulus of the PVA nanocomposites improved by 47 % and 36 %, respectively. The presence of LNP also enhanced the thermal stability of the materials. Significantly, the proposed sonochemical process may be generally applicable to the synthesis of a range of naturally-derived LNPs for a variety of value-added applications.

In situ biomonitoring using caged lumpfish (Cyclopterus lumpus) eggs reveal plastic and rubber associated chemicals in a harbour area in Central Norway

ABSTRACT Plastics- and rubber-derived chemicals are given increasing focus due to their migration into the environment and potential for causing detrimental effects. The current study demonstrates the use of a novel biomonitoring platform using caged fertilized eggs of lumpfish (Cyclopterus lumpus) in combination with gas chromatography tandem mass spectrometry analysis of a selection of target chemicals extracted from the lumpfish eggs after deployment. A monitoring campaign in the Trondheim harbor and off the coast of Trøndelag in Norway was executed using the described system. Here we found accumulation of UV stabilizers (benzophenone and benzothiazoles), plasticizers (n-butylbenzenesulfonamide), reagents, and polymer synthesis precursors (bisphenol A, acetophenone, phthalide, and phthalimide) in deployed eggs. Several of the compounds were detected in concentrations above previously quantified legacy contaminants in the same study areas.

Pengendalian Kualitas Produk KemasanDengan Metode Statistical Quality Control Dan Failure Mode And Effect Analysis (PT. Temprina Media Grafika)

PT. Temprina Media Grafika is a manufacturing company with printing and packaging services. The products are produced from PT. Temprina Media Grafika are packaging paper for various industrial products. However, the production of PT. Temprina Media Grafika still has a few problems that impact the product flaw. The purpose of this study is to identify the quality of Emart Choco Wafer Roll packaging and offer improvements to improving the Emart Choco Wafer Roll packaged products in PT. Temprina Media Grafika. The study was used are Statistical Quality Control (SQC) and Failure Mode and Effect Analysis (FMEA). Based on the results of research on Statistical Quality Control (SQC), the most dominant defects were color not appropriate (27,2%), after that shiny color not right (23,4%), uneven colors (21,9%), Spots appear on the pack (15,3%), and packaging design cut (12,3%). Based on the results of research on Failure Mode and Effect Analysis (FMEA), it is known that the problem causing disability with the highest RPN value of 168 is the machine factor with the cause of dirty UV polymer containers. Recommendations for improvements that can be made are Eliminating uv polymer containers after uv laminate processes.

Coral-friendly and non-transdermal polymeric UV filter via the Biginelli reaction for in vivo UV protection

Coral-friendly and non-transdermal polymeric UV filter via the Biginelli reaction for in vivo UV protection

Vacuum Arc Plasma Coating for Polymer Surface Protection— A Plasma Enhanced In-Orbit Additive Manufacturing Concept

In-orbit additive manufacturing (AM) is a promising approach for fabrication of large structures. It allows to expand and accelerate human space exploration possibilities. Extrusion-based AM was demonstrated in zero gravity, while the realization of such a process in orbit-like vacuum conditions is currently under exploration. Still, a solution for protection of the UV and IR radiation sensitive polymers is needed in order to prevent their early mechanical failure under space conditions. Vacuum arc plasma based process is widely applied on earth for thin protective coating deposition. Its major advantage is its scalability—from tiny size used in electric propulsion to large scale coating devices. The usability of the vacuum arc process in space conditions was shown in electric propulsion applications in nano-satellites. In this work we discuss and demonstrate the integration of vacuum arc process as a post processing step after Fused Filament Fabrication (FFF) for additive manufacturing and functionalization of long polymer structures. Here we address the concept for technical realization, which integrates the vacuum arc into additive manufacturing process chain. More over we present a laboratory prototype, which implements this concept together with a use case, where a previously printed PEEK structure is coated with aluminum based coating suitable for UV radiation protection.

English

The goal of this paper is to study the impact of a differential mass loss or a lack of material (void) directly located into the core structure of matter together with the possibility of measuring its effect by a resonant signal surface at optical frequencies. To this end, the focus has been on the evolution of effective indices or eigenvalues of micro-resonators as relevant models. Specific lack of mass was measured by way of a resonant optical signal principle. Then, specific families of resonators have been designed and shaped with several slits nano-inscribed upon them. The signal resonant light is then characterized by its pseudo-period while considering the whole geometry, taking account of the void; thus, it contains the information regarding the pre-defined recessed volume. The study was carried out first by controlling the deep UV technology onto an organic so as to fabricate the family of slotted micro-resonators before assessing the evolution of the effective index of the system that is inversely proportional to the free spectral range. Experimentally, the design of the measurement platform made it possible to measure the impact of a given lack of material within the cyclic resonators. Experimental measurements have been carried out so as to confirm previous simulations demonstrating a convergence ranging from 0.09 to 0.39%. Accordingly, the relevant results allow us to validate a quantified description regarding the hollowed out volume (or mass recessed within the core waveguide) with regard to the spatial resonant optical signal. Key words: Deep UV210 polymer, nano-inscribed slots, micro-resonators, optical resonance monitoring, lack of material, void characterizations.

Design of Polymeric Corrosion Inhibitors Based on Ionic Coumarate Groups.

Efficient, environmentally friendly organic corrosion inhibitors are being sought to alleviate the financial loss caused by corrosion degradation of mild steel materials. Here, we show the synthesis and characterization of monomeric ionic coumarate corrosion inhibitors and their integration into polymeric acrylic UV coatings. For this purpose, we investigated the effect of including the coumarate corrosion inhibitors into the acrylic UV coating by three different means. The corrosion inhibitors could be added as a standalone ionic liquid additive, or they can be ionically attached or covalently attached to the acrylic polymer network. To achieve this, two methacrylic monomers and one nonpolymerizable ionic coumarate compound were synthesized. The anticorrosion properties of the three coumarate compounds when added to a chloride aqueous solution were investigated by various techniques. Next, the three ionic coumarate compounds were integrated into an acrylic UV polymer composition. Here, the UV coating, which shows the best anticorrosion performance, was the one where the coumarate group is attached covalently or ionically to the polymer. The UV coating, which included the coumarate compound as a nonreactive additive, presented leaching problems from the coating, limiting its anticorrosion effect. The work herein shows that the development of polymeric corrosion inhibitors that combine the barrier properties of the polymer coating and the anticorrosive identity of the organic inhibitor is a powerful strategy to prevent corrosion.

Solid State Optical Microlasers Fabrication via Microfluidic Channels

In this paper, we propose the use of a microfluidic channel with flow focusing technique to fabricate solid state polymeric microlasers to precisely control sizes for mass production. Microlasers are made from a solution of UV curable polymer, namely polyethylene glycol diacrylate (PEGDA) with a molecular weight of 700 and rhodamine 6G laser dye at two different volumetric ratios (polymer to dye) of 4:1 and 2:1, respectively, which are used as the dispersed phase. A reservoir filled with liquid polydimethylsiloxane (PDMS) was used to cure the microlasers via UV lamp. A microchannel made of (PDMS) and size of 200 µm was used in this paper; mineral oil was selected as the continuous phase. Two experiments are conducted by fixing the pressure flow for the dispersed phase to 188 mbar and 479.9 mbar, respectively. In both experiments, the pressure of the continuous phase (mineral oil) was varied between 1666.9 mbar and 1996.9 mbar. The measurement of the fabricated microlasers’ size was performed with the aid of the MATLAB Image Processing Toolbox by using photographs taken with a CMOS camera. The tunability of the highest size, ranging from 109 µm to 72 µm, was found for the PEGDA to dye ratio of 2:1 (188 mbar) and average standard deviation of 1.49 µm, while no tunability was found for the 4:1 ratio (188 mbar). The tunability of the microlaser’s size, ranging from 139 µm to 130 µm and an average standard deviation value of 1.47 µm, was found for the 4:1 ratio (479.9 mbar). The fabricated microlasers presented a quality factor Q of the order 104, which is suitable for sensing applications. This technique can be used to control the size of the fabrication of a high number of solid state microlaser based UV polymers mixed with laser dyes.

Biorenewable functional oligomers and polymers – Direct copolymerization of ferulic acid to obtain polymeric UV absorbers and multifunctional materials

Ferulic acid (FA) (3-methoxy-4-hydroxy-cinnamic acid) is obtained from biowaste such as bran of rice, wheat and maize. It possesses tremendous potential for making polymers suited to specialty applications. This manuscript describes the use of FA directly to produce functional polymers useful for making aqueous dispersions, films and other materials with multifunctional characteristics. pH responsive polymers were also prepared for the first time by using off-the-shelf reagents in one step. In the case of pH responsive polymers the absorption maximum (λmax) varied with pH of the medium. The pH responsive polymers were further modified to zwitterioninc polymers and UV absorbing polymeric quaternary ammonium salts. Zwitterionic polymers dispersed well in water. Hydrolytic studies in phosphate buffer indicated that the stability of polymers depended on the chemical structure. The polymers are potentially useful as UV absorbing films and biorenewable multifunctional materials.

Behavior of photopolymer fiber structures in microgravity

Tackling the need of more research on the field of space deployable structures, this study aims to explore the concept of space manufacturing. The target is to acquire insight that shall be useful for future deep space missions, where the in situ production of components and repair procedures shall be mission critical. In particular, the objective of this study was to deploy and cure, pneumatically actuated fiber reinforced UV polymer beam structures in micro-gravity. Then, the specimens were tested in the laboratory to identify the effects of micro-gravity on the microstructure, macrostructure, thermal and mechanical behavior of the composite material, by comparing the 0-g specimens with a 1-g control group. This research was performed by participation in the ESA—European Space Agency Fly Your Thesis! 2017 programme and the 68th ESA Parabolic Flight Campaign, through which, access to the Novespace’s Zero-G aircraft laboratory was allowed.

Light-Responsive Serinol-Based Polyurethane Nanocarrier for Controlled Drug Release.

In the present work, a new and facile strategy for the synthesis of light-responsive polyurethanes (LrPUs) based on serinol with o-nitrobenzyl pendent groups is developed. Stable monodisperse nanoparticles from these LrPUs can be formulated reproducibly in a simple manner, which is shown by dynamic light scattering (DLS) measurements. Upon irradiation with UV light, both polymers and nanoparticles undergo rapid degradation, which is investigated by DLS, scanning electron microscopy, size exclusion chromatography, and UV-vis spectroscopy. The nanoparticles are also employed for the encapsulation of the model drug Nile Red, and by exposure to UV light, a burst release of the payload is detected via fluorescence spectroscopy. This strategy can be easily applied to the straightforward synthesis of various new serinol-based monomers with different stimuli-responsive properties and therefore expand the family of biodegradable polymers.

Synthesis and Comparative Biological Properties of Ag-PEG Nanoparticles with Tunable Morphologies from Janus to Multi-Core Shell Structure.

Silver nanoparticles synthesized with polymers as coating agents is an effective method to overcome their poor stability and aggregation in solution. Silver-polyethylene glycol (Ag-PEG) nanoparticles were synthesized with the thiol-functionalized polyethylene glycol (SH-PEA) as the coating, reducing and stabilizing agent. The UV irradiation time, polymer and silver nitrate concentration for the synthesis were investigated. The concentration of silver nitrate had significant effect on the morphology of Ag-PEG nanoparticles. When increasing the concentration of silver nitrate, SEM and TEM images showed that Ag-PEG nanoparticles changed from Janus to multi-core shell structure. Meanwhile, pure silver particles in the two hybrid nanoparticles presented spherical shape and had the similar size of 15 nm. The antibacterial activities and cytotoxicity of the two structural Ag-PEG nanoparticles were investigated to understand colloid morphology effect on the properties of AgNPs. The results of antibacterial activities showed that the two structural Ag-PEG nanoparticles exhibited strong antibacterial activities against Staphylococcus aureus, Escherichia coli and Bacillus subtilis. The Janus nanoparticles had larger minimal inhibitory concentration (MIC) and minimum bacterial concentration (MBC) values than the multi-core shell counterparts. The results of cytotoxicity showed the Janus Ag-PEG nanoparticles had lower toxicity than the multi-core shell nanoparticles.

Simple fabrication of high focal number micro-lenses based on a microfluid pulse jetting method

In this paper, we demonstrate a simple and rapid high focal number (F # ) micro-lens (ML) fabrication method using a simple microfluid pulse jetting technology. The simulation of the microfluid pulse jetting is firstly studied to prove that the new jetting method have the potential for jetting the UV polymer with a low surface tension coefficient stably. As the high F # of the ML is ascribed to the low contact angle of the ML on the substrate, a simple surface treatment of the substrate is adopted to obtain a small contact angle of the UV polymer on the substrate. Based on this method, the spherical ML and cylindrical ML with a F # as high as 11.5 have been successfully fabricated. The fabricated high F # ML is characterized through simulating the modulation transfer function curve, wavefront aberration, and point spread function (PSF) and measuring the PSF and imaging effect, and the simulation and measurement results indicate that the diffraction limit optical performance of the high F # ML can be achieved and the clear images can be observed.

UV Radiation Detection Using Optical Sensor Based on Eu3+ Doped PMMA

AbstractProgress in UV treatment applications requires new compact and sensor constructions. In the paper a hybrid (organic-inorganic) rare-earth-based polymeric UV sensor construction is proposed. The efficient luminescence of poly(methyl) methacrylate (PMMA) matrix doped by europium was used for testing the optical sensor (optrode) construction. The europium complex assures effective luminescence in the visible range with well determined multi-peak spectrum emission enabling construction of the optrode. The fabricated UV optical fibre sensor was used for determination of Nd:YAG laser intensity measurements at the third harmonic (355 nm) in the radiation power range 5.0-34.0 mW. The multi-peak luminescence spectrum was used for optimization of the measurement formula. The composition of luminescent peak intensity enables to increase the slope of sensitivity up to −2.8 mW-1. The obtained results and advantages of the optical fibre construction enable to apply it in numerous UV detection systems.

Characterization and comparison of three microfabrication methods to generate out-of-plane microvortices for single cell rotation and 3D imaging

This paper presents three different microfabrication technologies for manufacturing out-of-plane, flat-bottomed, undercut trapezoidal structures for generating a fluidic microscale vortex (microvortex). The first method is based on anisotropic silicon etching and a ‘sandwich’ UV polymer casting assembly; the second method uses a backside diffuser photolithography technique; and the third method features a tilted backside photolithography technique. We discuss the advantages, limitations, and utility of each technique. We further demonstrate that the microvortex generated in the resultant undercut trapezoidal structures can be used to rotate biological microparticles, e.g. single, live cells for multiperspective, high resolution 3D imaging using computed tomography, and angularly resolved confocal imaging.

Advantages of UV210 polymer for integrated optics applications: comparison of ridge and photoinscripted strip waveguide performances

We report on the propagation performance comparison of two waveguide structures obtained from the same UV210 photoresist. Ridge waveguide structures were fabricated by deep ultraviolet photolithography, and photoinscripted strip waveguides were realized by the same process, excluding the last development step. Structural and optical studies were carried out for both waveguide families, highlighting a well-controlled photolithography process. Predictions of the propagating modes were also led using the beam propagation method, showing a good agreement with experiments in single-mode propagation. Propagation losses were evaluated at 635 nm by cut-back measurement, showing mean loss values that are slightly lower for photoinscripted waveguides than for ridge waveguides. UV210 photoinscripted waveguides thus combine a fast and low-cost process, reduced optical losses, and a planar surface with as many advantages for more complex integrated components.

A laterally coupled UV210 polymer racetrack micro-resonator for thermal tunability and glucose sensing capability

We report and demonstrate the feasibility of a laterally coupled racetrack microresonator based on UV210 photoresist to act as a thermal and glucose sensor. The large thermo-optic coefficient and the detection principle based on the interaction of the evanescent field with different glucose concentrations demonstrate that this sensor displays high sensitivity on detection properties. Deep-UV lithography procedures allow us to develop a laterally coupled microresonator with submicrometer patterns. The thermo-optic response of the racetrack microresonator is interrogated by using a NiCr alloy tip positioned on the top of the device. Temperatures ranging between 19 and 33oC yield a red shift of the resonant wavelength with a linear sensitivity of 220 pm oC-1. Additionally, the thermal tunability is successively demonstrated by covering the resonator with DI water. A blue shift of the resonant wavelength is obtained with a linear sensitivity of 200 pm oC-1. The resonance optical properties under this top cladding conditions lead a Q-factor of 4000 with a finesse of 5.7. Glucose homogeneous sensing capability is also experimentally demonstrated. Different concentrations of glucose solutions result in a red shift of the resonant wavelengths with a linear sensitivity of 280 pm/(mg/ml). Finally, these results validate the laterally coupled racetrack microresonator as an operative photonic component for integrated optical devices such as optical filters applied on telecommunication, or transducer components devoted to assess biochemical interactions.

All-polymer photonic crystal slab sensor.

An all-polymer photonic crystal slab sensor is presented, and shown to exhibit narrow resonant reflection with a FWHM of less than 1 nm and a sensitivity of 31 nm/RIU when sensing media with refractive indices around that of water. This results in a detection limit of 4.5 × 10(-6) RIU when measured in conjunction with a spectrometer of 12 pm/pixel resolution. The device is a two-layer structure, composed of a low refractive index polymer with a periodically modulated surface height, covered with a smooth upper-surface high refractive index inorganic-organic hybrid polymer modified with ZrO2based nanoparticles. Furthermore, it is fabricated using inexpensive vacuum-less techniques involving only UV nanoreplication and polymer spin-casting, and is thus well suited for single-use biological and refractive index sensing applications.