Polymethyl Methacrylate Sheet Research Articles

Facile preparation of graphene–graphene oxide liquid cells and their application in liquid-phase STEM imaging of Pt atoms

Graphene–graphene oxide (GO) hybrid liquid cells (LCs) for liquid-phase scanning transmission electron microscopy (STEM) were fabricated using a facile method with commercial graphene on a polymethyl methacrylate sheet and GO on a TEM grid. LCs containing Pt nanoparticles (NPs) and pure water were efficiently produced and observed via STEM. Their composition and thickness were characterized by STEM-electron energy-loss spectroscopy. High-resolution (HR) STEM revealed slow-moving Pt NPs’ atomic structures and fast-moving single Pt atoms at the LC’s thin edges. Minimal damage during HR STEM indicated stable LCs because of their excellent electrical and thermal conductivities and radiolysis species scavenging ability.

Microfluidic aerosol-assisted synthesis of gefitinib anticancer drug nanocarrier based on chitosan natural polymer

An aerosol-assisted approach was devised to synthesize gefitinib anticancer drug-loaded chitosan nanocarriers (GefNCs). The nanocarrier synthesis involves mixing and interacting gefitinib molecules with chitosan natural polymer within a microfluidic chip. The combination was nebulized with an on-chip integrated micropneumatic nebulizer with N2 as the nebulizer gas. The aerosol was collected in a beaker containing a glutaraldehyde cross-linking agent while magnetically stirring. The chip was created by CO2 laser engraving on polymethyl methacrylate sheets. The synthesized GefNCs were characterized using FTIR, DLS, FESEM, and TEM. The FESEM images revealed a nanoparticle size distribution of 18.5 ± 4.6 nm. After adjusting numerous experimental parameters such as chip design, polymer concentration, solution flow rate, and nebulizer gas flow rate, the synthesized nanocarrier's release mechanism was investigated using various kinetic models. The results demonstrated that the release behavior of GefNCs is pH-sensitive and greater at acidic pH values than physiological pH, making the synthesized nanocarrier a potential for targeted gefitinib delivery to cancer cells. Furthermore, the kinetic studies revealed that the drug's release mechanism best matches Fick's diffusion rule. Under optimal conditions, the encapsulation efficiency was 77.8 %. The cytotoxicity of the produced nanocarrier was investigated on the A549 non-small cell lung carcinoma. The MTT test revealed that the produced nanocarrier had a lower IC50 than the free medication. Furthermore, cytotoxicity experiments on empty nanocarriers revealed that the materials utilized to synthesize nanocarriers have no appreciable cytotoxicity. The developed microfluidic-assisted approach provides a quicker synthesis procedure with a high encapsulation efficiency.

Investigating the Laser engraving on Polymethyl methacrylate sheets and process parameters optimization using GRA technique.

Abstract Polymethyl methacrylate (PMMA) is sound-resistant because it can lessen the transmission of outside sound waves. PMMA is widely used in many applications, such as automotive lighting, electronics and energy, health, sanitation, etc. Laser engraving for PMMA sheet panels with process parameters of good quality is a major problem in the process industry. There is a demand for surface roughness that is affected by the volume of material removal. Therefore, in this work, multi-value response optimization was performed on MRR and surface roughness during laser engraving of PMMA sheets using an optical fiber diode in a dry environment through gray relational analysis. Also, regression models are developed, and their responses are compared for their correlation. The GRA combined with the Taguchi method has proved efficient in the decision-making of multi-responses in a laser engraving environment.

Exploring the impact of polyvinylidenefluoride membrane physical properties on the enrichment efficacy of microfluidic electro-membrane extraction of acidic drugs

Membrane technology has revolutionized various fields with its energy efficiency, versatility, user-friendliness, and adaptability. This study introduces a microfluidic chip, comprised of silicone rubber and polymethylmethacrylate (PMMA) sheets to explore the impacts of polymeric support morphology on electro-membrane extraction efficiency, representing a pioneering exploration in this field. In this research, three polyvinylidenefluoride (PVDF) membranes with distinct pore sizes were fabricated and their characteristics were assessed through field-emission scanning electron microscopy (FESEM), and atomic force microscopy (AFM). This investigation centers on the extraction of three widely prescribed non-steroidal anti-inflammatory drugs: aspirin (ASA), naproxen (NAP), and ibuprofen (IBU). Quantitative parameters in the extraction process including voltage, donor phase flow rate, and acceptor phase composition were optimized, considering the type of membrane as a qualitative factor. To assess the performance of the fabricated PVDF membranes, a comparative analysis with a commercially available Polypropylene (PP) membrane was conducted. Efficient enrichment factors of 30.86, 23.15, and 21.06 were attained for ASA, NAP, and IBU, respectively, from urine samples under optimal conditions using the optimum PVDF membrane. Significantly, the choice of the ideal membrane amplified the purification levels of ASA, NAP, and IBU by factors of 1.6, 7.5, and 40, respectively.

A numerical and experimental analysis of CO2 laser micro-milling on PMMA sheet considering a multipass approach for microfluidic devices

Laser-assisted machining is an advanced manufacturing process that provides excellent cutting quality, flexibility, and precision. The current study used a CO2 laser to create microchannels in polymethyl methacrylate (PMMA) sheets using a series of laser passes by varyingparameters such as laser power (30–40 Watt), number of passes (1–4), and cutting speed (20–25 mm/s). A finite element analysis is performed using ABAQUS with subroutines such as Distributed Flux (DFLUX) and User Defined Field (USDFLD) to simulate and predict the upper and lower kerf width, kerf angle, and heat-affected zone (HAZ) during the process. Thermal analysis has been performed by considering the laser beam as body heat flux with a moving heat source. It has been observed that the HAZ tends to reduce with the increase of laser cutting speed. During the laser cutting process, the upper kerf width is found to increase with increasing laser power, as well as with increasing the number of passes at a given laser power and cutting speed. It is also predictedthat when laser cutting speed increases, the kerf width for a given laser power decreases. The experimental and simulation results are in good agreement and the results demonstrated thatthe average percentage error in HAZ, kerf angle,upper kerf, and lower kerf width was 3.21 %, 5.06 %, 7.60 %, and 22.2 %, respectively. The results of this study have significance for the advancement of precise and state-of-the-art manufacturing for application in microfluidic devices.

Fabrication of a 96-electrode array using carbon dioxide laser ablation

The 96 laser-induced multigraphene electrode (96L-MGE) integrated microwell plate (96 L-MGE-MP) is described. Each cell includes separate working, auxiliary, and reference electrodes, and the array sits on a poly-methyl methacrylate (PMMA) well. The 96 electrochemical cells were fabricated by laser ablation of polyimide adhesive tape, which created laser-induced graphene electrodes (L-GE). The microwell was produced using laser ablation of the PMMA sheet as well. The morphology and electrochemical characterization of L-GE were controlled by tuning the laser processing. L-GE fabricated at laser power–laser speed ratios of 0.008–0.02 W s mm–1displayed good electrochemical behaviors. Under the optimal condition of L-GE fabrication, the measured L-GE surface roughness was 475.47 nm. The 96 L-MGE can be fabricated in 24.2 min and is compatible with various analytes. 10 benchmark redox compounds were shown as electrocatalytic examples. The performance of each analyte was investigated by voltammetry. As proof of concept, 96 L-MGE-MP was connected to a 96× connector for multichannel detection. The RSD of the 96 L-MGE-MPwas below 5.3%, which demonstrated good fabrication reproducibility.

Optimization of Laser Cutting Parameters for PMMA Using Metaheuristic Algorithms

This study fixates on determining the optimum laser input parameters that simultaneously meet the desired kerf width and depth during CO2 laser cutting of various polymethylmethacrylate (PMMA) sheets. It has three contributions. The first is to model the cutting process of PMMA by polynomial curve fitting as a function of laser power, laser speed, and standoff distance. R-squared (R2), adjusted R2 and root-mean-square error (RMSE) criteria were taken into account to measure the performance of the proposed model. The effect of laser parameters on the process is investigated by analysis of variance (ANOVA) and sensitivity analysis. The second is to optimize the derived nonlinear regression models using genetic algorithm (GA), particle swarm optimization (PSO), whale optimization algorithm (WOA) and ant lion optimization (ALO) metaheuristic methods and compare the performances of the algorithms. The third is to compare the adequacy of the optimization process with the artificial neural network (ANN). The investigations exhibited that the best-fitting polynomials are obtained with the R2 and adjusted R2 values of over 99% and 97%, respectively. ANOVA and sensitivity test revealed that the sensitivity of the laser power, which is the most effective parameter, was 150 at low powers and decreased to 0 as the power value increased. When the nozzle distance is 4.1, the proposed metaheuristics gave effective and sufficiently accurate results. PSO stood out in terms of both best cost value (3.49 × 10–8) and relative error value (0.19%). The relative error of the ANN was found as 3% in terms of kerf depth.

Investigation of Laser Cutting of Thin Polymethyl Methacrylate Sheets by Response Surface Methodology

Investigation of Laser Cutting of Thin Polymethyl Methacrylate Sheets by Response Surface Methodology

Laser induced fluorescence technology for early detection of diabetes via optical fiber microfluidic sensor

This research explores the use of direct write laser technology to reduce manufacturing costs and time by using Polymethyl methacrylate (PMMA) sheet. The process has a maximum channel width of 208 µm for zigzag channels and 205.66 µm for straight channels, limiting droplet miniaturization. Microfluidics technology offers potential for creating graphene, glucose, and rhodamine B biosensor devices for various applications. Combining these materials offers benefits like miniaturization, reduced response time and chemical consumption, and improved device reproducibility and sensitivity. The study also highlights advancements in chip materials, device assembly, and material preparation for graphene-based microfluidic sensors. The findings show that optical fiber microfluidic biosensor devices have higher spectral resolution than traditional fluorescence spectrometers, enabling precise identification of mixture components and fluorescence enhancement analyses.

PMMA based compound kinoform lenses for sub-150 nm hard x-rays focusing

It is the first time to fabricate the polymethyl methacrylate (PMMA) based compound kinoform lenses (CKLs) for nano-focusing of hard x-rays. The PMMA CKLs with a physical aperture of 160 µm and a focal length of 20 mm are designed and fabricated by x-ray LIGA technology at the Beijing Synchrotron Radiation Facility. To improve the stiffness of the PMMA lines, PMMA sheets with high molecular weight are fabricated, and the results revealed that the PMMA lines with higher molecular weight were much stronger. After optimization, CKLs with the narrowest lines of 4 µm width can achieve 110 µm height and 2.99 nm surface roughness without deformation. The CKLs were tested at the Diamond Light Source, which provided a focal width of 122 nm for 12 keV x rays. Though the PMMA has a poor radiation tolerance, it has a better process tolerance, and it can lay a good foundation for the fabrication of SU8 based CKLs by LIGA technology, which has a better radiation tolerance. Compared to the Si CKLs fabricated by dry etching, the PMMA CKLs are higher in depth, smoother at the sidewall, and have better nanofocusing.

Unsaturated polyester resin/polymethylmethacrylate waveguide-based refractive index sensor with dual-wavelength temperature compensation

This paper demonstrates an optical waveguide based- refractive index (RI) sensor using the temperature compensation method. The optical waveguide was formed using a polymethylmethacrylate sheet as the cladding material and unsaturated polyester resin as the core material. The sensor design consists of two input waveguide branches, a sensing area and an output branch. Two light emitting diodes with wavelength of 530 nm and 660 nm were used as light sources. In this work, temperature compensation was done by dual-wavelength technique in which RI and temperature sensitivities were measured at two different wavelengths at 530 nm and 660 nm. Based on the RI and temperature sensitivities, temperature compensation was implemented. Experimental findings indicated that the average relative error of the uncompensated measurement using the light source of 530 nm and 660 nm were 0.4372% and 0.2749%, respectively. Meanwhile, the average error of the temperature compensation method was 0.0344%. Hence, the temperature compensation method provides measurement error up to 92% lower compared to the uncompensated method. As such, the proposed dual-wavelength compensation method could effectively improve the RI measurement accuracy.

Polarization response characteristics of 6061Al and PMMA sheets under impact load

The material will induce shock polarization under the action of shock wave. Aluminum alloys (such as 6061Al) are used as the main material for spacecraft skins, panels and frames. The impact polarization effect generated during the cratering deformation (compression and shearing) of space debris will induce the surface discharge of the orbiting satellite. Polymethyl methacrylate (PMMA) materials are often used in combination with electronic devices of weapon equipment. Under high overload, PMMA will produce shock polarization effect, electromagnetic interference on electronic devices, and even trigger by mistake. Therefore, it is of great significance to reveal the impact polarization characteristics of different types of materials (metal, polymer) for improving the bulletproof protection ability of in-orbit satellites, protective armor and electronic devices. In this paper, the 6061Al and PMMA thin plates were taken as the research object, and the universal testing machine combined with LCR was used to measure the capacitance and resistance of 6061Al and PMMA under different given loads by combining theoretical analysis, experiment and simulation. At the same time, the first stage light gas gun is used to study the local impact induced electro-mechanical response of metal and polymer sheet materials. On this basis, the AUTODYN-ABAQUS/Explicit-COMSOL co-simulation under corresponding experimental conditions was carried out to obtain the distribution rules of temperature and strain gradient. Based on the theory of flexoelectric effect, the impact polarization response characteristics of 6061Al and PMMA materials were clarified, respectively. The results show that the impulse polarization voltage of 6061Al thin plate increases first and then gradually decreases with time. The impulse polarization voltage is proportional to the thickness. The polarization voltage of single-electrode PMMA thin plate is parabola; the polarization voltage of PMMA thin plate with two electrodes increases first and then gradually decreases. The absolute value of the strain gradient of the 6061Al thin plate increases first and then becomes stable, while the strain gradient of the PMMA thin plate increases first and then decreases.

Business Roundup

BUSINESS Business Roundup ShareShare onFacebookTwitterWechatLinked InRedditEmail C&EN, 2023, 101 (12), p 11April 10, 2023Cite this:C&EN 101, 12, 11AbstractLanxess and the private equity firm Advent International have finished forming a polymers joint venture after their purchase of DSM’s engineering polymers business for $4.2 billion. Lanxess will own about 40% of the partnership, called Envalior, and is receiving a payment from Advent of about $1.4 billion. Linde has signed an agreement with ExxonMobil to transport and store 2.2 million metric tons per year of carbon dioxide emissions from a clean hydrogen plant that Linde plans to build in Beaumont, Texas. Linde will supply the hydrogen to OCI for an ammonia plant. Trinseo is selling the buildings and equipment at its Matamoros, Mexico, site, which makes polymethylmethacrylate sheet, to Plaskolite, which will continue to make similar products. Trinseo is consolidating its own production into its plant in Kentucky. Ethos Asset Management , a US project finance company, has arranged funding that will enable Green Glycols to build a biobased propyleneView: PDF | Full Text HTML

Low-pressure plasma treated polycarbonate and polymethyl methacrylate (PMMA) sheets with different surface patterns to change their surface properties

Low-pressure plasmas of carbon tetrafluoride (CF4), oxygen (O2), and air were used to treat the surfaces of polycarbonate (PC) and polymethyl methacrylate (PMMA) to achieve a variety of surface attributes, such as hydrophilicity, hydrophobicity, and surface free energy. Patterns of straight line, triangular and square shapes with different sizes e.g., 0.5 mm, 0.75 mm, and 1 mm dimensions as templates were constructed from stainless-steel sheets with a thickness of 1 mm, via laser cutter, were used to induce the corresponding shape of the functionality on PC and PMMA surfaces during plasma gas treatment were also investigated. The untreated PC and PMMA surfaces have a contact angle (θ) value of 70°±0.47° and 77°±0.80°, respectively. As expected upon CF4 plasma treatment, their contact angle values were increased to 109.04°±0.35° and 105.76°±0.61°, respectively; whereas the air plasma treated surfaces became more hydrophilic with the contact angle values of 29.34°±0.14° and 43.99°±0.22°, correspondingly. Moreover, O2 plasma treated surfaces became more hydrophilic with the contact angle values of 25.32°±0.77° for PC and 39.94°±2.05° for PMMA. Also, surface free energy (SFE) values were decreased to 11±0.87 mN/m from 41.16±0.42 mN/m for PC and to 12.11±1.53 mN/m from 35.93±1.12 mN/m for PMMA upon CF4 treated surfaces. Furthermore, SFE values were increased to 57.59±1.12 and 62.13±1.15 mN/m for PC and PMMA after air plasma treatment. PC surface's, advancing and receding contact angles were determined as 101.48°±0.33° and 65.60°±0.11° respectively for 34.77°±0.50° slide-off angles. Moreover, the advancing and receding contact angles for PMMA were found as 93°±0.64° and 61.60°±1.19°, respectively with a sliding angle of 24.49°±1.14°. X-ray Photoelectron Spectroscopy (XPS) analysis results confirmed the fluorination and oxidation of both PC and PMMA after CF4 and O2 plasma treatments, individually. PC and PMMA surfaces were treated multiple times with CF4 and Air, Air and CF4, O2 and CF4, and CF4 and O2 plasmas in succession. After multiple treatment, PC and PMMA surfaces contact angle values were decreased as low as 10.62°±0.88° and 14.96°±0.2°, respectively.

Trinseo is trimming capacity, mostly in Europe

Trinseo is cutting uncompetitive manufacturing capacity in a program that it hopes will boost its profitability by $60 million annually. The polymer maker is moving forward with the closure of its styrene plant in Böhlen, Germany. The Pennsylvania-based firm unveiled plans to close this plant in September, saying it had lost $30 million over a prior 12-month period. The company blames the plant’s small size as well as high European natural gas costs. Trinseo is also closing an uncompetitive polycarbonate line at its plant in Stade, Germany. It will continue serving its own polycarbonate compounding business with the plant’s remaining capacity. Trinseo is closing a polymethyl methacrylate sheet plant in Matamoros, Mexico. It will also shut down a styrene-butadiene latex plant in Hamina, Finland, next year because of regional overcapacity in that market. Trinseo anticipates taking charges of up to $89 million because of the closures.

Experimental investigations and modeling for multi-pass laser micro-milling by soft computing-physics informed machine learning on PMMA sheet using CO2 laser

Laser micro-machining has gained significant attraction from industries and researchers due to the wide range of processability and material flexibility with micro-scale accuracy. However, only a few process variables and soft computing approaches are taken into consideration in micro-scale sectors. This provides the opportunity to explore a new and relatively unexplored area of physics-informed advanced soft computing techniques for laser beam machining. This study aims to develop a framework to investigate the micro-milling capabilities of 10 mm thick poly-methyl-methacrylate (PMMA) using various input parameters such as laser power (8–16 W), scanning speed (25–50 mm/s), number of passes (2–6), and incident energy (0.107–0.64 J/mm). A soft computing technique to build depth, width and surface roughness prediction models on a CO2 laser machine, is presented. Advanced soft computing approaches such as random forest, gradient boost, ridge regression, linear regression, support vector regression and gaussian process regression are evaluated to predict the microchannel's depth, surface roughness, and kerf width. The proposed work is validated experimentally and compared with the different prediction/regression models available in the literature. The values of hyper tuning parameters are optimized using by grid search method. Based on the 5-fold cross-validation analysis, the most accurate predictions of the depth, surface roughness and kerf width could be achieved through the gaussian process regression (GPR) model with highest accuracy of 98.34 %, 97.68 % and 96.38 % for depth, surface roughness and kerf width respectively.

Surface Modification of Polymethylmethacrylate (PMMA) by Ultraviolet (UV) Irradiation and IPA Rinsing.

Polymethylmethacrylate (PMMA) is commonly applied to microfluidic devices due to its excellent biocompatibility, high optical transparency, and suitability for mass production. Recently, various surface treatment methods have been reported to improve the wettability of polymers, which is directly related to adhesion. In this research, the effect of a UV irradiation technique and an IPA rinsing technique as surface treatments for PMMA is investigated regarding the water contact angle of the PMMA surface. PMMA sheets that were 1.62 mm thick and commercially available were exposed to UV light with four different exposure times. Significant decreases in the water contact angle were observed after exposure to UV light, and the lowered contact angles due to the UV irradiation increased over time. According to the measurement, the water contact angle is a function of UV exposure dose as well as storage time after UV exposure. We examined the effect of a IPA rinsing process after UV irradiation and observed an increase in the water contact angle.

Entrapment of Airborne Particles via Simulated Highway Noise-Induced Piezoelectricity in PMMA and EPDM

The US highway system features a huge flux of energy transportation in terms of weight, speed, volume, flow density, and noise levels, with accompanying environmental effects. The adverse effects of high-volume traffic cause health concerns for nearby residential areas. Both chronic and acute exposure to PM 2.5 have detrimental effects on respiratory and cardiovascular health, and motor vehicles contribute 25–35% of direct PM 2.5 emissions. In addition to traffic-related pollutants, residing near major roadways is also associated with exposure to increased noise, and both affect the health and quality of life of residents. While regulatory and policy actions may reduce some exposures, engineering means may offer novel and significant methods to address these critical health and environmental issues. The goal of this study was to harvest highway-noise energy to induce surface charge via a piezoelectric material to entrap airborne particles, including PM 2.5. In this study, we experimentally investigated the piezoelectric effect of a polymethyl methacrylate (PMMA) sheet and ethylene propylene diene monomer (EPDM) rubber foam on the entrapment of copper (II)-2,4 pentanedione powder (Cu II powder). Appreciable voltages were induced on the surfaces of the PMMA via mechanical vibrations, leading to the effective entrapment of the Cu II powder. The EPDM rubber foam was found to attract a large amount of Cu II powder under simulated highway noise in a wide range, of 30–70 dB, and at frequencies of 700–1300 Hz, generated by using a loudspeaker. The amount of Cu II powder entrapped on the EPDM rubber-foam surfaces was found to scale with the SPL, but was independent of frequency. The experimental findings from this research provide a valuable base for the design of a robust piezoelectric system that is self-powered by harvesting the wasted sound energy from highway noise and reduces the amount of airborne particles over highways for effective environmental control.

Preparation of PMMA/SiO2 Composite Sheets for Tribological and Mechanical Tests

This paper aims to prepare PMMA sheets (Polymethyl methacrylate sheets) reinforced with SiO2 nanoparticles (Silicon oxide nanoparticles) to obtain samples for tribological and mechanical tests. PMMA reinforced sheets are prepared by three methods; dissolving, pressing, and casting. In the first method, the pure PMMA granules were dissolved with an organic solvent. The SiO2 nanoparticles were dispersed using a magnetic stirrer. Then, the solution was poured into a glassy mold. In the second method, pure PMMA powder was used, and SiO2 nanoparticles were dispersed using a nanoparticle disperser device; then, the mixture was placed in a metal mold and pressed by a thermo-hydraulic press. While in the third method, pure PMMA resin and hardener were used, and SiO2 nanoparticles were dispersed using an ultrasonic probe machine, and then the mixture was poured into a glassy mold. The three preparation results showed that the obtained sheets were free of bubbles and that their surfaces were of excellent smoothness and could be cut using a laser to obtain the samples required for tribological and mechanical tests such as tensile test, impact test, wear test, surface hardness test, surface roughness test, and scratch resistance test and others.

Through-thickness strain field measurement of polymethyl methacrylate sheet using phase-contrast optical coherence tomography

Strain field characterization for evaluating the mechanical properties of polymethyl methacrylate (PMMA) is highly significant. This study establishes a method based on phase-contrast optical coherence tomography for the through-thickness strain field measurement of PMMA sheets, which utilizes two methods of probing light passing through the specimen thickness in parallel or oblique to estimate thickness shrinkage and elongation. Two PMMA sheet specimens were measured under stretching for the validation test—one with and the other without a slotted hole. The results show that all the measured strain fields are non-uniform, stress concentration occurs in the defect, and Poisson's ratio of PMMA in this paper is 0.35–0.37. These results indicate good rationality, proving the feasibility of the proposed method for strain measurements.