Use Of Resin Research Articles

Online Detection of Radioactive Iodine in Aqueous Systems through the Use of Scintillating Anion Exchange Resin

The objective of this research was to develop a scintillating anion exchange resin selective for monitoring (129)I at concentrations at or below ~0.4 Bq/L. One of the primary long-term risk-drivers and contaminants associated with nuclear waste sites is (129)I. Synthesis of scintillating anion exchange resin consisted of diffusing a fluor, 2-(1-naphthyl)-5-phenyloxazole (α-NPO), into a polymeric resin. The resultant scintillating resin was further modified by amination with N-methyldi-n-octylamine (MDOA) to serve as an anion exchange group. Radiochromatography columns were prepared with the synthesized resin for use in a variety of flow-cell experiments utilizing a standard (129)I solution in a synthetic groundwater to determine the properties (selectivity, interferences, loading efficiency, kinetics, capacity, and detection efficiency) of the resin. Column effluents were quantified by liquid scintillation. Average loading and detection efficiencies have been measured at 91 ± 9% and 50 ± 4%, respectively. Finally, batch sorption studies indicated fast iodide sorption rates (90% loading in ~10 min) for the resin, and dynamic sorption tracer studies indicated an iodide capacity of approximately 7,800 μg/g at 10% breakthrough.

A newly developed salicylanilide functionalized Amberlite XAD-16 chelating resin for use in preconcentration and determination of trace metal ions from environmental and biological samples

Salicylanilide has been incorporated into Amberlite XAD-16 through an azo spacer. Characterization of the synthesized resin was done on the basis of elemental analyses, infra-red spectral and thermal studies. The water regain value and hydrogen ion capacity were found to be 12.90 and 6.08 mmol g−1 respectively. The optimum pH values for the maximum sorption of analyte were 9.0 for Cu(II), Co(II), Ni(II), Zn(II), Cr(III), and 6.0 for Cd(II) and Pb(II), respectively, with the half-loading time, t1/2, ranging from 3.5 to 11.0 min. The breakthrough capacities for Cu(II), Co(II), Ni(II), Zn(II), Cr(III), Cd(II), and Pb(II) were found to be 697.91, 641.83, 629.32, 551.38, 531.72, 249.11 and 125.36 μmol g−1, respectively, with corresponding preconcentration factors of 440, 380, 380, 360, 280, 280 and 260. The detection limits were found to be 0.56, 0.64, 0.65, 0.70, 0.75, 0.88 and 1.17 μg L−1, respectively. Analysis of standard reference materials and recovery experiments were carried out for the validation of the method. Practical utility has been demonstrated by successfully determining metal ions in natural water, mango pulp, leafy vegetables and fish.

Development of Siliconized Epoxy Resins and Their Application as Anticorrosive Coatings

The present work involves the development of siliconized epoxy resin to overcome the drawback of epoxy resin like poor impact strength, high rigidity and moisture absorbing nature because of which they are not applied as corrosion resistant coating. By embedding silicone into the back bone of polymeric resin the above drawback can be reduced to substantial level. For achieving this, siliconised epoxy resins were prepared by reacting amine terminated silicone resin with novolac epoxy resin and meta-phenylenediamine was used as curing agent. The applied films of coating were baked at 150oC. Cured films were evaluated for their thermal, mechanical, chemical and corrosion resistance properties to ascertain the commercial utility of these eco-friendly resin for use in anti corrosive formulations. The siliconized epoxy resins system was found to exhibit good thermal and anticorrosive properties.

プリント配線板を支える高分子材料 プリント配線板の現状と今後の展望

Personal digital assistants (PDA), such as cellular phones, personal computers and car navigation systems, supporting the ubiquitous society, is expected to be the smart phones which have above mentioned all functions and evolve to ultimate wearable PDAs. High density LSI packaging technologies have been realized the superior performance and function of communication electronics products and printed wiring boards have played very important role to meet these requirements. Here, after brief introduction of the history and the categories, the technologies and the recent trend for the printed wiring boards are introduced, especially focusing on the thermosetting polymer materials. As the future prospect, we pay attention to the automotive electronics field, concretely the power device packaging technologies. High heat resistant and low thermal expansion resins such as polyaromatic epoxy resins, benzoxazine resins and cyanate resins for power semiconductor module are developed. Power semiconductor devices are key devices for carbon dioxide reduction technology. As another approach, the effective use of biomass resources as industrial materials plays an important role. Lignin is a plant biomass and is classified as a polyphenol and investigated a suitable alternative to fossil-fuel-derived phenol resins for use in the thermosetting epoxy resins.

A green and efficient protocol for industrial-scale preparation of dioscin from Dioscorea nipponica Makino by two-step macroporous resin column chromatography

A green and efficient method for the large-scale preparation of dioscin from Dioscorea nipponica Makino, a well known traditional Chinese medicinal herb, was developed. The preparation procedure consisted of two separation steps. In the first step, several types of macroporous resins including NKA-II, DA201, DM-301, AB-8, D1400, D4020, X-5, HPD-100 and D101 were investigated in order to choose the best resin. D101 resin was selected according to its adsorption and desorption properties. Other parameters during static and dynamic procedures were also investigated. In order to obtain a pure target, a second step was established, which involved the screening of various types of macroporous resins (D900, D318, D315, D280 and D301). The results demonstrated that D900 resin was the most suitable resin for use in this study. Under these conditions, the large-scale preparation of dioscin was carried out. The purity of dioscin after the first step was increased 9.16-fold from 9.35% to 85.64% with a recovery of 81.47%. The purity of dioscin then increased to 96.55% with a recovery of 89.64% after the second purification. A total of 1.486 kg of pure dioscin was produced from 100.0 kg raw material by the developed two-step macroporous resin column chromatography method using only aqueous ethanol as the solvent. Our study provides a green and efficient protocol for industrial-scale preparation of dioscin for pharmaceutical use.

Organic solvent based TiO2 dispersion paste for dye-sensitized solar cells prepared by industrial production level procedure

In order to prepare the TiO2 liquid dispersions for the electrodes of dye-sensitized solar cells with indus- trial mass production level at a reasonable cost, the present study investigates the preparation of TiO2 liquid disper- sions by a general industrial dispersion technique using readily available P25. To determine the TiO2 dispersion offering the best light-electricity energy conversion effi- ciency, the suitability of various types of solvents and resins for use in TiO2 dispersion are tested. In general, organic solvent based TiO2 dispersions are found to allow the formation of more uniform thin films in comparison with water-based dispersions. A preparation using ethyl cellulose as the resin and the terpineol as the solvent is found to exhibit the best conversion efficiency. We have also found that using two kinds of resins of different molecular weights gave rise to better efficiency. Among 26 metal compounds tested in this study, the best metal dopant was Ag. XRD and XPS measurements confirm that the Ag exists as metal Ag and silver oxide.

Thermal and electrochemical durability of carbonaceous composites used as a bipolar plate of proton exchange membrane fuel cell

Thermal and electrochemical durability of carbonaceous composite plates, which are made from graphite powders and a resin for use as bipolar plates of PEMFC (proton exchange membrane fuel cell), were investigated. The thermal durability was investigated by TG (thermal gravimetry) coupled with DTA (differential thermal analysis) technique under air up to 600 °C. A weight loss was significant over 300 °C, but the hydrophobicity was decreased after heated at 80 °C for 192 h. The electrochemical durability was investigated in 10 μmol dm −3 of hydrochloric acid solution under nitrogen or oxygen atmosphere by means of potential holding test from 0.8 to 1.5 V against RHE (reversible hydrogen electrode) at 80 °C. During the potential holding tests, CO 2 production due to the corrosion was quantified by a GC (gas-chromatography) and the production was detectable above 1.3 V irrespective with atmosphere; on the other hand, it was clarified from the contact angle measurements that the hydrophobicity was changed below 1.3 V. The results of this study showed that the carbonaceous composite plates were electrochemically degraded under PEMFC condition and were seriously degraded in URFC (unitized regenerative fuel cell) condition.

Improving the mechanical properties of fiber-reinforced acrylic denture-base resin

This study evaluated the effects of different oligomers and silane-treated filler on the bending strength, bending modulus, compressive strength and compressive modulus of a fiber-reinforced acrylic resin for use in denture bases. The results showed that the investigated oligomers only improved the bending modulus. Using an inorganic filler treated with two types of silanes – γ-methacryloxypropyltrimethoxy silane and triethoxyvinyl silane – considerably improved the mechanical properties of the fiber-reinforced acrylic resin except for the bending strength, with triethoxyvinyl silane being more effective than γ-methacryloxypropyltrimethoxy silane. The improvement of the mechanical properties of fiber-reinforced acrylic resin is the incorporation of triethoxyvinyl silane-treated filler.

Acrylic Nanocomposite Resins for Use in Stereolithography and Structural Light Modulation Based Rapid Prototyping and Rapid Manufacturing Technologies

AbstractA novel family of optically transparent acrylic nanocomposites containing up to 30 wt % silica nanoparticles with an average diameter of 20 nm was developed for application in structural light modulation (SLM) and stereolithography (SL) technologies. The uniform dispersion of nanoparticles affords a significantly improved toughness/stiffness‐balance of the photopolymerized and postcured nanocomposites. It is possible to increase stiffness, as expressed by Young's modulus, from 1290 to 1700 MPa without encountering the embrittlement typical for many other conventional filled polymers. Fracture behaviour is examined by means of fracture mechanics investigation and SEM analyses of fracture surfaces. According to TEM analyses and measurement of optical transmittance remarkable uniform dispersion of silica nanoparticles was achieved. The silica nanoparticle concentrations up to 17 wt % give only marginally higher viscosities and do not affect transmittance, while slightly increasing the exposure times needed in photopolymerization. Moreover, the silica nanoparticles afford materials with reduced shrinkage and improved properties. The green effective ankle splay out (EASO) measured on H‐shaped diagnostic specimens, is significantly reduced for the nanocomposite materials from 1.38 mm for the unfilled material to 0.82 mm for nanocomposites containing 30 wt % nanosilica. The building accuracy is increased significantly with increasing content of silica nanofillers.

Electroless and Electrolytic Plating of Ni, Cu, and CoxFe2-xO4 for the Application of Three-Dimensional Micro-Molding

We investigated the combination of electroless and electrolytic plating of nickel, copper, and ferrite onto photopolymerized resin for use in the molding of three-dimensional micro-structures. The micro-molding process consists of four steps: fabrication of the resinous mold via two-photon micro-polymerization, plating of the mold, electrolytic grinding to open the interior structure, and extraction. A non-conductive epoxy resin was plated with nickel, copper, or ferrite through the electroless process, and then, the second layer composed of the other material was grown by the electroless or electrolytic plating. We found that the every combination of the three materials is available. The electrolytic plating was useful for applying a thick film with high purity.

Optical Nanoimprint using Plastic Template and Visible Light-Curable Resin

To eliminate the releasing defects of template in UV nanoimprint lithography (NIL), a novel process without using anti-sticking layer is proposed in combination with a plastic template and a visible light (VL)-curable resin. We newly use poly-propylene (PP) as a plastic template, which has low surface energy and is easily removed from polymers. However, plastic materials such as PP have generally poor transmittance for UV light, but have certain transmittance for VL. We apply a newly developed VL-curable resin for use of the plastic template. Using the VL-curable resin, the anti-reflection structure is successfully fabricated on a triacetylcellulose (TAC) film by the optical NIL from the PP template. With respect to the anti-reflection structure, the experimental result of reflectance shows less than 0.5%.

Scratch resistance of different silica filled resins for obturation materials

The authors have synthesised new silica filled polymeric resins for use as dental obturation materials. In contrast to earlier materials prepared for similar purposes, the present ones contain up to 80% silica nanoparticles providing the materials with improved mechanical properties. Scratch testing results show low values of the penetration depths. The ceramic concentrations used exceed a threshold concentration needed to change the mechanical properties from a soft polymer to a rigid ceramic. Further addition of silica has only insignificant effects on tribology. The penetration depths vary more or less linearly with the load, while viscoelastic recovery has a more complicated dependence on the load. These new materials have scratch resistance values in the range appropriate for applications as obturation materials.

FEM calculations of capillary rheometer flow for carbon‐filled liquid crystal polymer composites

AbstractThere is an emerging market for conductive resins for use in fuel cell bipolar plates. This research focuses on developing a finite element model of a capillary rheometer. Comsol Multiphysics 3.2b was used to model the flow of a remeltable thermoplastic matrix material, Vectra A950RX Liquid Crystal Polymer, with varying amounts of either a carbon black or synthetic graphite filler, to obtain the velocity profile and pressure drop of these composites within the capillary. Previous experimental results have shown that the molten composites obey a shear‐thinning power law behavior. When comparing the model predicted pressure drops from the model with the experimental data, very good agreement was obtained. This signifies that the rheological behavior of the composites can be described by a power law relationship, using parameters specific to each composite. When comparing the modeled velocity profile with the theoretical profile, it was found for all composite formulations that the velocity becomes fully developed within a length of 0.05 times the diameter of the tube, independent of the power law parameters n and m. This work is a necessary first step in developing 2D or 3D mold filling simulations for fuel cell bipolar plate applications. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007

A new colorimetric test for detection of hydroxyl groups in solid-phase synthesis

A new colorimetric test (methyl red-DIC test) for monitoring the presence of hydroxyl groups on resins for use in solid-phase synthesis was developed. The resin became orange-red when the carboxyl group of methyl red formed ester linkages with the resin’s hydroxyl groups. This new test can be used not only for qualitative analysis but also quantitative analysis by using pictures of the relationship between color depth and hydroxy loading rates.

Electroless and Electrolytic Plating of Photopolymerized Resin for Use in the Micro-Molding of Three-Dimensional Nickel Structures

We investigated the electroless and electrolytic plating of photopolymerized resin for use in the molding of three-dimensional nickel micro-structures. The micro-molding process consists of four steps: fabrication of the resin mold, electroless plating of the mold, electrolytic grinding to open the interior structure, and extraction. An epoxy resin mold, which is suitable for two-photon micro-polymerization, was successfully plated with nickel through this electroless process. Electrolytic plating was found to be useful for applying a thick nickel film on non-conductive resin with low crystal lattice distortion and few impurities. Regarding the design of the mold opening, it was shown that electroless plating does not proceed inside non-through-holes on the sub-millimeter scale, but that it proceeds inside through-holes with a diameter of 550 μm and down to the depth of 2 mm.

Electroless and Electrolytic Plating of Photopolymerized Resin for Use in the Micro-Molding of Three-Dimensional Nickel Structures

Electroless and Electrolytic Plating of Photopolymerized Resin for Use in the Micro-Molding of Three-Dimensional Nickel Structures

Improved guayule lines outperform old lines in south-east Queensland

Guayule ( Parthenium argentatum Gray) is a source of high quality rubber and low-allergenic latex as well as resin for use as a wood preservative. Demand for high value latex products has increased with the advent of deadly diseases such as AIDS. The objective of this study was to evaluate the performance of six improved guayule lines (AZ-1 to AZ-6) in south-east Queensland: released jointly by the Agricultural Research Service (ARS) of the United States Department of Agriculture (USDA) and The University of Arizona. Trials were conducted at two sites, Chinchilla and Gatton. Overall performance of improved lines for plant growth and yield of dry matter, rubber and resin was better at both Gatton and Chinchilla than the standard check lines (N 565 and 11591). AZ-1 and AZ-2 maintained the best combinations of desirable traits, including plant uniformity, early vigorous growth, increased dry matter, and increased rubber and resin yields. Of these two, AZ-2 had more uniform plant growth and has commercial potential for Queensland production areas. In the summer harvest at Gatton, 32-month-old AZ-1 and AZ-2 produced rubber yields of 789 kg/ha and 771 kg/ha, respectively, while controls, N 565 and 11591 produced 675 kg/ha and 618 kg/ha, respectively. At Chinchilla, at 33 months, spring harvested AZ-1 and AZ-2 produced rubber yields of 717 kg/ha and 787 kg/ha; these yields were significantly higher than N 565 and 11591 which produced 385 kg/ha and 380 kg/ha, respectively. Thus, rubber yields of AZ-1 and AZ-2 were consistently high across sites. AZ-1 and AZ-2 produced resin yields of 1158 kg/ha and 1115 kg/ha at Gatton and 1318 kg/ha and 1476 kg/ha at Chinchilla. This compared with a mean of 612 kg/ha and 352 kg/ha for the standard check lines at Gatton and Chinchilla. Thus resin yields of AZ-1 and AZ-2 were consistently high across sites. Rubber content appeared to be influenced by time of harvest although this effect is compounded with plant age. At Gatton, in spring, 17-month-old plants produced a mean rubber content of 7.7% (all lines), while, in summer, when the plants were 32-month-olds, rubber content dropped to 6.4%. At Chinchilla, 33-month-old plants harvested in spring produced a mean rubber content of 7.4%, similar to the spring value at Gatton. By contrast, resin content appeared to be little affected by season.

Properties of low-formaldehyde-emission particleboard made from recycled wood-waste chips sprayed with PMDI/PF resin

The objective of this study was to manufacture low-formaldehyde-emission particleboard from recycled wood-waste chips using polymeric 4,4′-methylenediphenyl isocyanate (PMDI) and phenol-formaldehyde (PF) resins for use in indoor environments. The influence of PMDI/PF ratios in particles on the formaldehyde emission and its mechanical properties were investigated. The experimental results showed that the formaldehyde emission released decreased linearly with increasing PMDI/PF particle ratio. The relationship could be represented by a linear regression formula. Formaldehyde emission was below 0.3mg/L when the weight percentage of PMDI/particles was up to 70%. The formaldehyde emission from melamine-formaldehyde (MF) resin-impregnated paper-overlaid particleboard was 17% lower than that for particleboard. Moreover, the bending strength, internal bonding strength and screw holding strength increased with increasing PMDI/PF particle ratio. However, the percentage thickness swelling of the particleboard decreased with increasing PMDI/PF particle ratio. In addition, there were significant positive relationships between the ultrasonic velocity and the bending strength, internal bonding strength and screw holding strength of the particleboard, which allowed evaluation of the properties of the particleboard using ultrasonic velocity.

Towards rapid screening of new composite matrix resins

A study to test the correlations among neat-resin and composite properties was performed, to identify possible ways of reducing the number of tests necessary to screen candidate resins for use in aerospace structures. Neat-resin and composite tests were conducted for four different resin matrices, whose neat properties varied over a wide range, allowing reasonably strong tests of correlations. Since different fiber architectures and fiber types are often of interest to a designer, tested correlations included those between composite coupons containing the same resin but with different fibers and lay-up. Composite structural properties were represented by unnotched tension, open-hole tension, unnotched compression, and open-hole compression. Correlations were sought between these and neat-resin properties, composite shear strength, and Mode I composite delamination toughness. Strong linear correlations, which are proposed to be the most useful because they discriminate best between different resin systems, were found in certain cases, but not others. Most significantly, an Iosipescu shear test for a [0°/90°] composite of one fiber type was shown to be a good predictor, for the tested resins, of open-hole compression and unnotched compression in composites with different fibers and architecture; and a fair predictor of open-hole tension. Open-hole tension strength was shown to correlate better with neat-resin fracture toughness, but neat-resin properties were otherwise inferior indicators of most composite properties. While data for further resins are needed to enrich the statistical base, some rationalizations can be found for the presence of the stronger correlations that were observed. The correlations described here suggest that reduced test matrices, containing tests for only Iosipescu composite shear and either neat-resin toughness or Mode I delamination toughness, may suffice to evaluate the likely structural performance of composites containing new candidate resins. The tests could be performed on a standard fiber type and architecture, yet be predictors for other fiber types and architecture.

Inlay shading effect on the photopolymerization kinetic of a dental composite material used as bonding system in an indirect restoration technique

To define the inlay shading effect on the polymerization levels and kinetics of a light activated bonding system for an indirect restoration technique. For the bonding system, an adhesive: Excite (Ivoclar-vivadent) and a composite: Z250 (3M-ESPE, St Paul Minnesota, USA) were investigated. A Demetron (Kerr USA) light curing unit was used. The composite inlay blocks of 2 mm thick were used for the experiment (Artglass A2 Heraeus, Kulzer, Dormagen, Germany). The bonding composite was photocured using a 2 mm composite inlay block as a shielding system while the adhesive was shielded by a 2.3 mm thick wafer, composed of the inlay material and the previously cured bonding composite. The kinetics and levels of polymerization were measured by a differential scanning calorimeter technique (DSC 25, Mettler, Orange, CA, Toledoh, küsnacht, switzerland). The inlay shielded dental composite reaches a significantly lower level of polymerization compared to the unshielded composite. Inlay shielded composite, has a slower polymerization kinetic compared to unshielded composite. The resin adhesive shielded by the inlay-composite wafer reaches polymerization values not significantly different from those of the unshielded adhesive. The degree of cure of the light-cured composite resins for use as a base for indirect composite restorations, may be severely reduced as a result of inlay shielding.