Ion-pair sorptive extraction of perfluorinated compounds from water with low-cost polymeric materials: Polyethersulfone vs polydimethylsiloxane

2012 ◽  
Vol 740 ◽  
pp. 50-57 ◽  
Author(s):  
Eugenia Villaverde-de-Sáa ◽  
Inés Racamonde ◽  
José Benito Quintana ◽  
Rosario Rodil ◽  
Rafael Cela
Keyword(s):  
Low Cost ◽  
Polymeric Materials ◽  
Ion Pair ◽  
Perfluorinated Compounds ◽  
Sorptive Extraction

Evaluation of low-cost disposable polymeric materials for sorptive extraction of organic pollutants in water samples

2012 ◽  
Vol 716 ◽  
pp. 119-127 ◽  
Author(s):  
Ailette Prieto ◽  
Rosario Rodil ◽  
José Benito Quintana ◽  
Isaac Rodríguez ◽  
Rafael Cela ◽  
...  
Keyword(s):  
Organic Pollutants ◽  
Water Samples ◽  
Low Cost ◽  
Polymeric Materials ◽  
Sorptive Extraction

Surface Modification of Poly(Vinylchloride) for Manufacturing Advanced Catheters

2020 ◽  
Vol 27 (10) ◽  
pp. 1616-1633 ◽  
Author(s):  
Oana Cristina Duta ◽  
Aurel Mihail Ţîţu ◽  
Alexandru Marin ◽  
Anton Ficai ◽  
Denisa Ficai ◽  
...  
Keyword(s):  
Surface Modification ◽  
Chemical Modification ◽  
Medical Devices ◽  
Low Cost ◽  
Physical And Mechanical Properties ◽  
Polymeric Materials ◽  
Modern Medicine ◽  
Structural Failure ◽  
Chemical Grafting ◽  
One Step

Polymeric materials, due to their excellent physicochemical properties and versatility found applicability in multiples areas, including biomaterials used in tissue regeneration, prosthetics (hip, artificial valves), medical devices, controlled drug delivery systems, etc. Medical devices and their applications are very important in modern medicine and the need to develop new materials with improved properties or to improve the existent materials is increasing every day. Numerous reasearches are activated in this domain in order to obtain materials/surfaces that does not have drawbacks such as structural failure, calcifications, infections or thrombosis. One of the most used material is poly(vinylchloride) (PVC) due to its unique properties, availability and low cost. The most common method used for obtaining tubular devices that meet the requirements of medical use is the surface modification of polymers without changing their physical and mechanical properties, in bulk. PVC is a hydrophobic polymer and therefore many research studies were conducted in order to increase the hydrophilicity of the surface by chemical modification in order to improve biocompatibility, to enhance wettability, reduce friction or to make lubricious or antimicrobial coatings. Surface modification of PVC can be achieved by several strategies, in only one step or, in some cases, in two or more steps by applying several techniques consecutively to obtain the desired modification / performances. The most common processes used for modifying the surface of PVC devices are: plasma treatment, corona discharge, chemical grafting, electric discharge, vapour deposition of metals, flame treatment, direct chemical modification (oxidation, hydrolysis, etc.) or even some physical modification of the roughness of the surface.

Materials Selection for Sandwich Pipes Under the Combined Effect of Pressure, Bending and Temperature

2007 ◽  
Author(s):  
Allan R. de Souza ◽  
Theodoro A. Netto ◽  
Ilson P. Pasqualino
Keyword(s):  
Structural Strength ◽  
Material Selection ◽  
Low Cost ◽  
Polymeric Materials ◽  
External Pressure ◽  
Core Material ◽  
Annular Layer ◽  
Oil And Natural Gas ◽  
Longitudinal Bending ◽  
Logic Approach

Recent researches point to the great potential of the sandwich pipe conception for ultra deepwater exploitation and production of oil and natural gas. Its configuration is very simple and comprises two concentric metallic pipes with a core material, polymeric or ceramic, in the annulus. The main functions of the annular layer are: to provide satisfactory thermal insulation so as to avoid the formation of wax and hydrates along the pipeline during production shutdown; to improve the overall structural strength of the system. Polypropylene and cement have been recently proposed for these applications. The reason for the choice of these materials was the low cost and the extensive availability in industry. Here a systematic material selection approach is employed in order to assess the applicability of other polymeric materials. The attributes of materials needed to meet the design specification are thoroughly studied. The list of possible materials was enlarged and the modified digital logic approach is used with the purpose to define a top group of materials for further numerical comparative study. Finite element analyses are carried out to assess the structural strength of the sandwich pipe under pure external pressure or longitudinal bending and combined external pressure and bending. Additionally, the effect of thermal gradient is included to the numerical analyses to evaluate each pre-selected material of the top group. Results indicate that other potential materials such as PEEK and polycarbonate can improve the structural performance of the sandwich pipe conception and yet meet other several design criteria.

Carbon Dioxide as a Carbon Resource – Recent Trends and Perspectives

2012 ◽  
Vol 67 (10) ◽  
pp. 961-975 ◽  
Author(s):  
Markus Hölscher ◽  
Christoph Gürtler ◽  
Wilhelm Keim ◽  
Thomas E. Müller ◽  
Martina Peters ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Raw Materials ◽  
Low Cost ◽  
Polymeric Materials ◽  
Short Review ◽  
Chemical Research ◽  
Bond Forming ◽  
Bulk Chemicals ◽  
High Thermodynamic Stability ◽  
Recent Trends

With the growing perception of industrialized societies that fossil raw materials are limited resources, academic chemical research and chemical industry have started to introduce novel catalytic technologies which aim at the development of economically competitive processes relying much more strongly on the use of alternative carbon feedstocks. Great interest is given world-wide to carbon dioxide (CO2) as it is part of the global carbon cycle, nontoxic, easily available in sufficient quantities anywhere in the industrialized world, and can be managed technically with ease, and at low cost. In principle carbon dioxide can be used to generate a large variety of synthetic products ranging from bulk chemicals like methanol and formic acid, through polymeric materials, to fine chemicals like aromatic acids useful in the pharmaceutical industry. Owing to the high thermodynamic stability of CO2, the energy constraints of chemical reactions have to be carefully analyzed to select promising processes. Furthermore, the high kinetic barriers for incorporation of CO2 into C-H or C-C bond forming reactions require that any novel transformation of CO2 must inevitably be associated with a novel catalytic technology. This short review comprises a selection of the most recent academic and industrial research developments mainly with regard to innovations in CO2 chemistry in the field of homogeneous catalysis and processes.

scholarly journals Influence of kaolin filler on the mechanical properties of Luffa cylindrica/ polyester composite

2021 ◽  
Author(s):  
Aliyu Yaro ◽  
Laminu Kuburi ◽  
Musa Abiodun Moshood
Keyword(s):  
Mechanical Properties ◽  
Polyester Resin ◽  
Unsaturated Polyester ◽  
Low Cost ◽  
Microstructural Analysis ◽  
Polymeric Materials ◽  
Weight Fraction ◽  
Industrial Applications ◽  
Luffa Cylindrica ◽  
Polyester Composite

Abstract Polymeric materials are used in different industrial applications because they retain good environmental properties, low-cost, and easy to produce compared to conventional materials. This study investigated the effect of adding kaolin micro-filler (KF) on the mechanical properties of Luffa Fiber (LCF) reinforced polyester resin. Luffa cylindrica fiber treated with 5% NaOH, varied in weight fraction (5, 10, and 15%wt) was used to reinforce unsaturated polyester resin using hand lay-up method, whereas for the hybrid composite kaolin filler were kept constant at 6wt% fraction while the fibers varied as in the mono-reinforced composite. The samples were machined for mechanical and microstructural analysis. Analysis of the result revealed that the addition of kaolin has enhanced greatly the mechanical properties of Luffa-fibre based composites. The result reveal of the microstructure analysis, shows that there is an improvement in fiber-matrix adhesion.

scholarly journals Enhanced Protein Immobilization on Polymers—A Plasma Surface Activation Study

Polymers ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 104 ◽  
Author(s):  
Felicia Wieland ◽  
Richard Bruch ◽  
Michael Bergmann ◽  
Stefan Partel ◽  
Gerald A. Urban ◽  
...  
Keyword(s):  
Substrate Temperature ◽  
Plasma Treatment ◽  
Surface Characterization ◽  
Low Cost ◽  
Substrate Surface ◽  
Polymeric Materials ◽  
Hydroxyl Groups ◽  
Surface Activation ◽  
Gas Composition ◽  
Characterization Methods

Over the last years, polymers have gained great attention as substrate material, because of the possibility to produce low-cost sensors in a high-throughput manner or for rapid prototyping and the wide variety of polymeric materials available with different features (like transparency, flexibility, stretchability, etc.). For almost all biosensing applications, the interaction between biomolecules (for example, antibodies, proteins or enzymes) and the employed substrate surface is highly important. In order to realize an effective biomolecule immobilization on polymers, different surface activation techniques, including chemical and physical methods, exist. Among them, plasma treatment offers an easy, fast and effective activation of the surfaces by micro/nanotexturing and generating functional groups (including carboxylic acids, amines, esters, aldehydes or hydroxyl groups). Hence, here we present a systematic and comprehensive plasma activation study of various polymeric surfaces by optimizing different parameters, including power, time, substrate temperature and gas composition. Thereby, the highest immobilization efficiency along with a homogenous biomolecule distribution is achieved with a 5-min plasma treatment under a gas composition of 50% oxygen and nitrogen, at a power of 1000 W and a substrate temperature of 80 °C. These results are also confirmed by different surface characterization methods, including SEM, XPS and contact angle measurements.

An experimental approach to manufacturability assessment of microfluidic devices produced by stereolithography

2020 ◽  
Vol 234 (24) ◽  
pp. 4905-4916
Author(s):  
Mattia Mele ◽  
Giampaolo Campana
Keyword(s):  
Regression Models ◽  
Low Cost ◽  
Dimensional Accuracy ◽  
Binary Logistic Regression ◽  
Polymeric Materials ◽  
Microfluidic Devices ◽  
Combined Effect ◽  
Manufacturing Cost ◽  
Linear Regression Models ◽  
Logistic Regression Models

Lab-on-a-Chips integrate a variety of laboratory functions and embed microchannels for small fluid volume handling. These devices are used in medicine, chemistry, and biotechnology applications but a large diffusion is limited due to the manufacturing cost of traditional processes. Additive Manufacturing offers affordable alternatives for the production of microfluidic devices, because the fabrication of embedded micrometric channels is enabled. Stereolithography gained particular attention due to the low cost of both available machines and suitable polymeric materials to be processed. The main restriction to the adoption of this technique comes from the obtainable dimensional accuracy that depends not only on design, but also on process set-up. Firstly, the paper analyses theoretically the physics of stereolithographic processes and focuses on main phenomena related to microchannel manufacturing. Then, specific experimental activities are designed to investigate the combined effect of design and process parameters on the achievable dimensional accuracy of embedded microchannels manufactured through a commercial desktop stereolithography apparatus. In particular, the combined effect of channel nominal dimensions, build orientations and the layer thickness on the obtainable accuracy is examined by referring to a benchmark geometry. The collated experimental data showed that a number of combinations are successful. Besides, the experimental activity revealed that appropriate combinations of design, build orientation and manufacturing parameters can overcome the dimensional limitations reported in previous studies. Both binary logistic regression models to predict the manufacturability of microchannels and linear regression models to estimate the achievable accuracy for those geometries that can be produced successfully are developed.

Creep Prediction of a Printed Wiring Board For Separable Land Grid Array Connector

2004 ◽  
Vol 127 (2) ◽  
pp. 185-188
Author(s):  
J. Cepeda-Rizo ◽  
Hsien-Yang Yeh
Keyword(s):  
Creep Behavior ◽  
Low Cost ◽  
Polymeric Materials ◽  
Superposition Method ◽  
Printed Wiring Board ◽  
Three Point Bending ◽  
Testing Method ◽  
Temperature Superposition ◽  
Mechanical Fastening ◽  
Wiring Board

The paper presents a study of creep behavior of a printed wiring board caused by the mechanical fastening of separable connector, known as a land grid array. Time-temperature superposition method was employed to predict the lifetime creep behavior. A low-cost testing method based on the ASTM D790 three-point bending procedure was developed to predict and characterize creep of polymeric materials under low temperature, low stress, and large elapsed times.

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