Soluble Resin Research Articles

The use of soluble resin for additive manufacturing of automotive industry prototypes

The article describes the method of producing car parts using the Freeform method (FIM). The injection process into a mold obtained by 3D printing was simulated and the surface condition of the finished product made of high-strength PEEK was assessed.

Synthesis and properties study of alkali soluble resin fortified polyacrylate latex

AbstractLatex films with high heat resistance tend to have higher Tg and the emulsion minimum film formation temperature (MFFT) is higher. Higher MFFT latexes do not produce continuous coherent films at low temperatures during application. Consequently, in order to solve the paradoxical problem of obtaining latex films with high Tg at low emulsion MFFT, a series of alkali soluble resin (ASR) stabilized latexes were synthesized in this study using a semi‐continuous pre‐emulsification polymerization process. The microstructure of latex particles, polymerization stability, composition and properties of latex films were characterized and tested by ATR‐FTIR, TEM, ZETA potential analyzer, DSC, orthomorphic metallographic microscope, and gloss tester. The results show that the addition of ASR reduces the content of coagulum during polymerization and significantly increases the number of latex particles. The high Tg ASR also induces the formation of a microphase separation structure with a dual glass transition in the latex film, which improves heat resistance. Additionally, hydroplasticized ASR reduces emulsion MFFT, improves latex film flatness, and enhances its glossiness. The introduction of ASR acts as a dual role of synergy with conventional ionic surfactants during synthesis to increase the stability of composite latexes and with polyacrylate (PA) in application to enhance its properties.

Solvent-free synthesis of oil-soluble fluorescent carbon dots for bright photoluminescent and electroluminescent light-emitting diodes

Fluorescent carbon dots (CDs) have attracted great attention in multidisciplinary fields due to their distinctive advantages of tunable emission, low toxicity and abundant raw materials. However, it is still a big challenge to effectively applicate these CDs in electroluminescent light-emitting diodes (LEDs) due to their poor oil solubility and easy aggregation-induced quenching. Herein, an oil-soluble fluorescent CDs is designed and synthesized using triphenylamine and 4-iodophenyldiphenylamine as precursors through a solvent-free reaction. The obtained CDs (TPA-CDs) display an emission peak at 551 nm with good oil-solubility in different organic solvents. Therefore, TPA-CDs can be used as the host material of emission layer to prepare monochromatic electroluminescent LEDs with a maximum luminance of 227 cd·m−2 and as guest material in PVK to demonstrate white light electroluminescent LED with a maximum luminance of 1503 cd·m−2. This CDs can also be mixed well with oil soluble resin to easily assemble photoluminescent devices with a high luminous efficiency of 17.1 lm·W−1. This is the first example that solvent-free synthesized CDs are used for both photoluminescent and electroluminescent devices.

Methacrylic acid‐based amphiphilic block‐random copolymer stabilizers for emulsion polymerization

AbstractThe emulsion polymerization of styrene was investigated using polystyrene‐b‐[polystyrene‐r‐poly(methacrylic acid)] amphiphilic block‐random copolymers (BRCs) of different compositions as stabilizers. These stabilizers with molar masses <20,000 g/mol, which possess unique dispersion behaviour (i.e., self‐assembly with low aggregation numbers) when dissolved in aqueous medium at alkaline pH, were prepared by the nitroxide‐mediated bulk polymerization of styrene to achieve a desired molar mass followed by chain extension by batchwise addition of styrene and methacrylic acid monomers to obtain the stabilizing group. Emulsion polymerizations of styrene stabilized by these BRCs yielded stable latexes with particle diameters that range between 30 and 150 nm. When different concentrations of the stabilizer (2–3.5 mM) were utilized for emulsion polymerization of styrene, a similar novel emulsion polymerization mechanism observed previously by our group for the acrylic‐acid based amphiphilic BRCs was also seen, further validating the difference between this class of polymeric surfactants and conventional small molecule surfactants, block copolymers, or alkali soluble resins. The performance of methacrylic‐acid based BRCs was more efficient and yielded higher surface coverage of the polystyrene latexes when compared to the acrylic‐acid based BRCs as a result of the more hydrophobic nature of the former.

Phase evolution and microstructure of SiC–MgAl2O4–Al composites sintered in argon atmosphere at 1450 °C: Reactions in Al–O–C system

SiC–MgAl2O4–Al composites were prepared using SiC, MgAl2O4, corundum and Al powder as raw materials by firing at 1450 °C in flowing argon. The effects of binders on phase composition and microstructure evolution were investigated. The results show that the external of specimens with thermosetting phenolic resin and water soluble resin as binders both contained SiC, MgAl2O4, corundum and Al4O4C phases. In center of the specimens, Al4C3 and Al2OC phases appeared in the thermosetting phenolic resin bonded specimens while Al4O4C and Al2OC phases appeared in the water soluble resin bonded specimens. The microstructure shows that MgAl2O4 whiskers generated at surface of both specimens through gas-gas reaction. As for the specimens with thermosetting phenolic resin as binder, the residual carbon (decomposed from phenolic resin) and Al in the external of the specimen react with O2 to form CO and Al2O, which promoting the formation of plate-like Al4O4C. In the center of the specimen, Al4C3, Al2O3 and Mg(g) formed. Mg(g) migrates to outside and transforms to MgAl2O4 whiskers, and a part of Al4C3 transform to columnar Al2OC. Al2OC whiskers can also be generated through the reaction among Al2O, CO and C. Compared with the thermosetting phenolic resin bonded specimens, Al at external of the water soluble resin bonded specimen reacts with O2 to form Al2O3, which further transforms to particle Al4O4C. In the center of water soluble resin bonded specimen, a little Al4C3 formed and can totally transform to Al4O4C and Al2OC.

Mechanical properties of films cast from alkali soluble resin stabilized latexes

Alkali soluble resins (ASRs) are often combined with polymer latexes in coatings formulations in order to provide stability to the latex as well as to improve the mechanical properties of films cast from the dispersions. In this work, we explore the influence that the alkali soluble resin has on the mechanical properties of films cast from a series of ASR stabilized styrene(St)/butyl acrylate(BA) copolymer latexes. Tensile test results show that in stark contrast to the mechanical properties of most films cast from latexes, the composition of the St/BA phase has virtually no influence on the Young's modulus and is largely dependent on the high Tg ASR phase, leading to very high values, on the order of 108 Pa. When the Tg of the St/BA phase increased, elongation break also increases leading to materials with high toughness, an observation which is again in contrast to the general behavior shown by films cast from homogeneous latexes. These unique mechanical properties, which are reminiscent of those of rubber toughened thermoplastics, are related to the continuous high Tg ASR phase that is formed upon drying. The influence of ethylene glycol and glycerol, common polar additives in coatings formulations, is also explored and it is shown that the polar ASR phase is selectively plasticized, leading to a significant decrease in mechanical performance.

Water-soluble sacrificial 3D printed molds for fast prototyping in ceramic injection molding

Fabrication of steel molds is a major expense (time and cost) in ceramic injection molding research and development. 3D printed resin molds for fast prototyping are therefore highly attractive and have gained increasing attention. This paper reports strategies to use sacrificial molds 3D printed by fused deposition modeling (FDM) from PVA or digital light processing (DLP) from water soluble resin. Usage of sacrificial molds allows injection molding of complex geometries, which are not accessible for simple two-part molds. Ceramic heating elements in diverse geometries were injection molded using a composite feedstock containing MoSi2, Al2O3 and feldspar. More parts with various geometries were produced from Al2O3 feedstock. A comparison revealed that DLP printed molds are better suited for parts with very small structural features due to the higher resolution of the DLP process as compared to FDM. Finally, ceramic heaters were fabricated using two-component ceramic injection molding and successfully tested.

Preparation and Evaluation of Captopril Oral Floating Controlled Release Formulations

Aim: Dosing frequency is a major hurdle in geriatrics with frequent drug administration. In such cases, oral controlled release floating formulations are helpful which causes reduction in dosing frequency and fluctuation of drug levels in plasma. The main aim of the current research was to prepare Captopril floating controlled release formulations in order to achieve extended gastric retention in the upper GIT.
 Methodology: Captopril tablets were prepared using different concentrations of poly ethylene oxide water soluble resin (PEO WSR) 303 (5% to 30%) by direct compression technique. Captopril formulations CSP1 and CSP6 were formulated using PEO WSR 303. Pre and post compression parameters were evaluated. Dissolution studies were performed for the prepared tablets using 0.1N hydrochloric acid as dissolution medium.
 Results: The dissolution studies showed controlled drug release up to 12h. The formulation CSP5 prepared using 25% w/w of PEO WSR 303 showed maximum drug release of 97.97% at 12h. Almost similar drug release profile was also observed for CSP6 which was prepared using 30%w/w PEO WSR 303. These two formulations were further added with various concentrations of sodium bicarbonate (5% to 15%) and citric acid (2.5% to 10%) which enhanced floating of drug in Gastro intestinal tract (GIT). Formulation CSP8 containing 10% of sodium bicarbonate with 25% PEO WSR 303 showed less buoyancy lag time and prolonged drug release. Formulation CSP15 showed very less buoyancy lag time of 5sec. Characterization studies like Fourier Transform Infra Red spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) were also carried out.
 Conclusion: The prepared Captopril floating tablets could be an alternative formulation for prolonged drug release.

Film formation of Alkali Soluble Resin (ASR) stabilized latexes

Alkali soluble resin (ASR) stabilized latexes are commonly employed in the development of waterborne coatings with good mechanical properties. However, despite their widespread use, little is known about how the nature of the hydroplasticized, high Tg ASR influences the film formation process and how systems can be designed to minimize the minimum film formation temperature (MFFT). In this work we synthesize a series of ASRs and ASR stabilized latexes in order to explore how the ASR influences the drying and deformation processes occurring during film formation. It is shown the ASR absorbs water and serves to increase the effective volume fraction of polymer during drying. Despite often being considered as an aqueous solution, the ASR behaves more like a conventional colloidal polymer and its film formation behavior is dictated by the wet Tg of the ASR. In ASR/latex blends both the wet Tg of the ASR and the Tg of the main emulsion polymer affects the MFFT. It is shown that high Tg ASRs (Tg > 100 °C) can be easily used in formulations that have MFFT <20 °C. In addition, for latexes with high Tg (Tg > 60 °C), using correct design strategies, hydroplasticized ASRs can be employed to lower the MFFT to below ambient temperature. These insights should allow for the effective development of latex films with low MFFT but mechanical properties more comparable to their solvent based counterparts.

Modification of concrete mortar using polyurethane resin

This paper presents an experimental investigation carried out to study the effects of non-water soluble Polyurethane Resin used in the modification of concrete mortar. The non-water soluble Polyurethane Resin (PU) was obtained from Fursa Industry and Tech Limited. The non-water soluble PU was used for this study do to its availability and low cost. Additives such as; Sulphur and Calcium Oxide responsible for binding and curing were used. Concrete mortar cubes of 50 x 50 x 50 mm respectively were produced with grade 42.5 Ordinary Portland Cement from Dangote Cement Limited. The ordinary Portland Cement was partially replaced with 0% (control), 15%, 25% and 35% non-water soluble Polyurethane Resin respectively. The influence of partial replacing Ordinary Portland Cement with non-water soluble Polyurethane was checked by testing the concrete mortar cubes for compressive strength testat7, 14 and 28 days respectively after casting and curing. It was observed that the addition of Polyurethane Resin as OPC partial replacement leads to considerable increase in compressive strength at 25% and 35% in comparison to the compressive strength of the control sample. The improvement in compressive strength was not significant beyond 35% Polyurethane replacement of OPC and was there accepted as the optimum percentage replacement.

Biobased Alkali Soluble Resins promoting supramolecular interactions in sustainable waterborne Pressure-Sensitive Adhesives: High performance and removability

Social environmental demands are increasingly promoting the development of low carbon footprint adhesive materials capable of providing excellent properties and ensuring clean removability. Herein, high performance and easy removable waterborne pressure-sensitive adhesives with biobased contents up to 71% stabilized with novel biobased alkali soluble resins (ASRs) have been successfully developed. 2-octyl acrylate (2OA), isobornyl methacrylate (IBOMA) and isosorbide (di)methacrylate (ISOMAraw) are the main biobased monomers used to synthesize the ASR and waterborne polymer dispersions. Pendant double bonds coming from isosorbide dimethacrylate promoted the grafting of the ASR resin, whereas hydrogen-bonding interactions provided by free OH groups create supramolecular interactions improving the viscoelastic character of the polymer network enhancing both the elasticity and energy dissipation of the pressure- sensitive adhesives along a greater range of frequencies (from 10−1 to 103 Hz). Furthermore, the presence of carboxylic groups in the pressure-sensitive adhesive compositions lead to a clean and fast removability of the adhesive tape from the glass substrate in basic media in 20 min. These novel biobased waterborne PSA compositions are ideal candidates for high performance applications where an easy and sustainable detachment after their use are required.

Experimental Investigations of Mechanical and Chemical Properties of PVP Precompressed Pressboard Insulation for HV Power Transformers

As the rating of power transformers increases, oil–paper insulation requirements become extremely difficult as insulation system should have more withstanding capabilities of high voltages and high reliability. Thus, it is important to find pressboards and precompressed pressboards using new insulating polymers with acceptable mechanical, chemical and electrical insulation properties that can used as an insulation barrier for high voltage–power transformers. The cellulose material-based pressboards are in great demand for high voltage–power transformers. Many researchers have investigated pressboards prepared from kraft pulp and found suitable in solid insulation of power transformers since decades. Pressboards are usually compressed with water soluble and insoluble polymer resins to develop precompressed pressboards. Water soluble insulating polymer resigns precompressed pressboards are of great importance, since they are recyclable. This paper mainly focuses on preparation of precompressed pressboards using a closed ring water soluble insulating polymer polyvinylpyrrolidone (PVP) and in order to ensure a correct functioning of this insulation in transformers, it is very important to characterize the mechanical and chemical properties of precompressed pressboards. These properties have been studied, and the results are compared with precompressed pressboard prepared from polyvinyl alcohol (PVA). It is observed that mechanical and chemical properties of PVP precompressed pressboards have shown substantial improvement compared to PVA precompressed pressboards.

Structure-property relationships in structural glass fibre reinforced composites from unsaturated polyester and inherently fire retardant phenolic resin matrix blends

The effects of matrices from co-cured blends of an unsaturated polyester (UP) with inherently fire-retardant and char-forming phenolic resoles (PH) on the mechanical and fire performances of resultant glass fibre-reinforced composites have been investigated. Three different phenolic resoles with increasing order of compatibility with UP have been used. These are: (i) an ethanol soluble resin, (PH–S), (ii) an epoxy-functionalised resin (PH-Ep), and (iii) an allyl-functionalised resin (PH–Al). The mechanical properties of the composites increased with increasing compatibility with two resin types as might be expected, but not previously demonstrated. However, even with the least compatible resin (PH–S), the impact properties were unaffected and the flexural/tensile properties while reduced, were still acceptable for certain applications. Fire properties were however, in reverse order as previously observed in cast resin samples from these composites. Moreover, the reduction in flammability was less compared to those of the cast resin samples, reported previously, explained here based on the insulating effect of glass fibre reinforcement.

Fabrication of Self-standing Polystyrene Thin Films with Fine Through Holes by use of Water Soluble Resin Sacrificial Layer

Fabrication of Self-standing Polystyrene Thin Films with Fine Through Holes by use of Water Soluble Resin Sacrificial Layer

Coated Powder Based Additive Manufacturing using Inkjet Technique

A new binder jetting process for fabricating metal or ceramic parts has been developed by using coated powder and inkjet technique. In this study, we have developed metal and ceramic particles coated with 100 nanometer thickness of water soluble resin in conjunction with a new concept of ink which includes cross linking agent that acts on the coated resin but does not include any binding ingredients. In this paper, we present a methodology of our new binder jetting process and an overview of mechanical and physical properties of 316L stainless steel parts created by our process.

Novel magnetic composites based on water soluble unsaturated polyester resin and iron oxide nanoparticles

Magnetic nanocomposites on the basis of water soluble unsaturated polyester resin filled with different amount of iron oxide nanoparticles have been successfully prepared. The mechanical properties of thus prepared composites as tensile, impact and flexural strength were determined. The specific volume and surface resistance of the magnetic nanocomposites were also determined.

Modification of heat storage ability and adhesive properties of core/shell structured phase change material nanocapsules

Phase change material-polystyrene (PCM-PSt) nanocapsules were prepared via a modified resin-fortified miniemulsion (RFME) polymerization process using an alkali soluble resin (ASR). Poly(styrene-co-acrylic acid) (SAA), which is a functional amphiphilic polymer, was used as the surfactant for the resin-fortified emulsion polymerization. A co-surfactant and a crosslinker were adopted to improve the PCM encapsulation efficiency. The average particle size and heat capacity of the optimized PCM-PSt nanocapsules were about ∼280 nm as measured by dynamic light scattering (DLS) and ∼110 J/g as measured by differential scanning calorimetry (DSC), respectively. The morphology and the inner structure of the nanocapsules were investigated using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The synthesized nanocapsules showed good adhesive and thermal storage properties, and were amenable for processing by dip-coating methods.

Clever House Made by Using a New Kind of the Nanocomposites

The materials of this paper concern a new nanocomposites perspective for construction. The development of research in the field of production and application of nanocomposite materials has made it possible to develop building materials, having high exploitation characteristics. One of such materials is a polydisperse armed water soluble epoxy composite coat, named “EpoxyPAN.” This material consists of the water soluble epoxy resin filled by the high strength inorganic fillers and the unique nanocarbon particles, astralenes and nanoporous microfiber. It was found that EpoxyPAN is possible to be used as effective water protection coating and simultaneously as effective electromagnetic waves absorber. The physical and exploitation properties of this nanocomposite and the possible ways of its applications for the Clever House constructions are also described in this paper.

Rheological characterization and shape control in gel-casting of nano-sized zirconia powders

In this study, a water soluble resin based gel system was developed incorporating nano-sized zirconia powders. The effects of the resin content and the solid loading on the rheological properties, density, mechanical properties and shape control have been investigated. All the slurries show typical shear-thinning behaviour. Higher resin-content leads to higher viscosity and larger green density. The density of the green component obtained from a slurry with 30wt% resin can reach 2.85g/cm3 (nearly 50% of the theoretical density). However, when the resin content is beyond 25wt%, the sintered density decreased. Higher density, solid-loading and applying external force are helpful to improve the shape control.

Use of historesin for viewing Batrachochytrium dendrobatidis in the mouth of Lithobates catesbeianus tadpoles (Rana catesbeiana Shaw, 1802), bullfrog

Abstract In 1998 an emerging disease, chytridiomycosis, was diagnosed, caused by the fungus, Batrachochytrium dendrobatidis, capable of infecting amphibians (Urodela and Anura) and it was considered to be the main cause of the global decline of these animals. Continuing the research work on the presence of this fungus in commercial flocks, tadpoles of bullfrogs were studied, where its presence was possibly found in the mouth of these animals using special histological techniques like historesin. Starting from the visual observation of the mouth of the tadpoles, it was observed that there was a discoloration of the partial structures of the denticles, which were typically dark in color and appeared whitish instead. The mouth of tadpoles with denticles was collected, and fixed in 10% buffered formalin. The inclusion of the biological material in glycol methacrylate (GMA) has been widely used due to a number of advantages over the usual histological methods, such as faster processing, water soluble resins eliminate the use of solvents, easy handling, obtaining semifine sections from 0.5 to 5 μm, highest resolution light microscope, and material is processed at room temperature thereby reducing distortions and artifacts. We used the commercial kit historesin FONTOVIT 7100 (Kulzer)®. After fixation in cacodylate buffer, dehydration increased in ethanol alcohol, pre-infiltrated with historesin diluted in alcohol, infiltrated with historesin pure and polymerized. Following mounting in acrylic and cut with automatic microtome. The staining can be performed with techniques used for inclusion in paraffin and is not necessary to hydrate or diaphanized cuts and color dyes suitable for fungi such as cotton blue and Congo red and hematoxylin–eosin. Slides were covered with Entellan® and coverslip. Characteristics of fungal structures, such as zoosporangia, single or grouped globular structures with discharge pipes for the removal of spores, were observed.