Use Of Resin Research Articles

Development of a three-dimensional printed model from a digital impression of a real patient for aesthetic dentistry undergraduate teaching.

The acquisition of skills and manual dexterity in aesthetic dentistry in undergraduate teaching requires preclinical practices with simulation that should approximate real clinical situations. We will present a digital procedure for the creation of three-dimensional (3D) resin models adapted to the practices of the Aesthetic Dentistry course. Stereolithography or Standard Tesellation Language (STL) files of a real patient were previously obtained with a 3-shape intraoral scanner. Using the Exocad computer programme for dental prosthesis design, various modifications were made, such as incisor rotation, surface alterations imitating dysplasias or erosions, the creation of diastemas, or even changes in tooth size. The virtual model was printed in resin for use by students. Once the practices were finished, the students and the teachers evaluated the use of the 3D printed models. The result is the typodont model, in which seven laboratory sessions took place: 1-Restoration of conoid tooth morphology, 2-Cervical abrasion/ erosion restoration, 3-Direct Composite Veneer, 4-Aesthetic correction in a tooth with rotation, 5-Diastem closure, 6-Occlusal abrasions/ erosion, and 7-Maryland bridge. 90.48% of the students evaluated the designed 3D model as the best method for laboratory practice compared to other methods, obtaining a general assessment of 8.3 out of 10. The method used has provided a reproducible standard analog model for direct aesthetic dental restoration practice, with a good assessment by students and teachers.

Aramid-Reinforced UV Curable Adhesive Resins for Use As an Interlayer in Laminated Glass.

Colorless, transparent, and mechanically robust aramid polymers are synthesized from two diamine monomers with strong electron-withdrawing groups, using low-temperature solution condensation with diacid chloride. The aramids dissolved very well in the liquid acrylamide monomers. When N,N-dimethylacrylamide (DMA) is used as a reactive diluent, films with the desired features are produced from the hybrid aramid-DMA resins via ultraviolet (UV)curing. The hybrid films are colorless and transparent in the visible region and showed an increase in the glass transition temperature, tensile strength, and elastic modulus in proportion to the aramid content. Laminated glass is manufactured using the hybrid resin as an interlayer, which exhibits very strong adhesion between the two sheets of glass, is not easily broken by an external impact, and do not scatter fragments. Moreover, the laminated glass do not distort images and functioned very effectively in UV blocking, soundproofing, and suppressing changes in the ambient temperature. Heat treatment further improves the light transmittance and impact resistance of the laminated glass. Laminated glass specimens with various fluorescence colors are also manufactured. Aramid-reinforced films prepared using N,N-diethylacrylamide as a reactive diluent underwent thermally induced phase separation in a wet state, providing smart glass with a privacy protection function.

Effect of nanosized carbon nanotubes, Titanium Nitride and cubic Boron Nitride powders on mechanical and thermal properties of SLA 3D printed resin composites

AbstractThis study explores the development of nanocomposites by incorporating multi‐walled carbon nanotubes (MWCNT), titanium nitride (TiN), and cubic boron nitride (c‐BN) nano powders into photo‐polymer epoxy resins for use in Stereolithography (SLA) additive manufacturing. Mechanical and thermal properties were systematically investigated to assess their performance. Initially, MWCNT, TiN, and c‐BN nano powders were homogeneously mixed with the resin to ensure uniformity. The resulting mixtures were then processed using SLA technology to evaluate production quality and material performance. The study revealed significant improvements in mechanical and thermal properties compared to pure resin, aligning with previous research outcomes. Specifically, the incorporation of MWCNT led to a notable enhancement in thermal conductivity, showing an increase of 24.21% as the thermal conductivity coefficient increased from 0.19 to 2.36 W/m·k. On the other hand, c‐BN significantly boosted mechanical strength, resulting in a substantial 20.45% increase as the shore D hardness went from 88.53 to 106.64. These findings highlight the promising potential of nanocomposites across various industries including electronics, aerospace, automotive, construction, medical devices, and manufacturing.Highlights Developed nanocomposites with MWCNT, TiN, and c‐BN in SLA resin. c‐BN increased hardness by 20.45%, proving its effectiveness in composites. MWCNT enhanced thermal conductivity by 24.21%, boosting material performance. Pioneering use of TiN and c‐BN in SLA, addressing gaps in existing research. Applications span electronics, aerospace, automotive and medical devices.

The Impact of Accelerated Light Ageing on MS3 for Use as a Picture Varnish

ABSTRACT This study provides an evaluation of MS3, a reduced polycyclohexanone resin, with key considerations for use as a picture varnish including solubility, removability, colour, and gloss and the stability of these factors. MS3 was first produced in 2016 as a replacement for the discontinued MS2A resin which was widely used as a conservation-grade picture varnish. Films of MS3 resin were artificially aged using UV-containing and UV-filtered light, representing the effects of daylight filtered through glass, and indoor museum lighting conditions respectively. Changes in colour and gloss of light-aged samples vs. control samples were measured, and solubility/removability was evaluated using selected solvents applied by hand-rolled swabs. FTIR spectroscopy was used to explore chemical changes of the varnish films following light ageing with respect to control samples. Empirical observations were made regarding the handling properties of MS3 dissolved in Stoddard solvent, and its behaviour as a retouching medium and varnish. The results suggest that MS3 exhibits a slight yellowing and a moderate increase in the polarity of solvent required for removal. No significant colour or solubility changes were observed in MS3 varnish films artificially aged using non-UV light. The results suggest that MS3 is a good substitute for MS2A resin for use as a picture varnish or retouching medium, based on the parameters measured.

Innovative Materials Based on Epoxy Resin for Use as Seat Elements in Bulk Transport.

The subject of this research is the development of epoxy composites with a defined service life for the purpose of seat elements in rail vehicles, which will be more environmentally friendly. The produced materials based on epoxy resin filled with PLA or PLA and quercetin were subjected to solar aging tests for 800 h to investigate the impact of the additives used on the aging behavior of the epoxy matrix. Firstly, the TGA analysis showed that the use of the proposed additives allowed for the maintenance of the thermal stability of the epoxy resin. Moreover, based on an optical microscopy test, it was noticed that the introduction of PLA and PLA with quercetin did not contribute to an increase in matrix defects. The one-directional tensile tests carried out before and after solar aging showed that the presence of polylactide in epoxy composites causes a slight growth of the stiffness and strength. Based on contact angle and color change measurements, it was found that quercetin was oxidized, thus ensuring protection for the epoxy matrix. This phenomenon was confirmed by FTIR study, where the carbonyl index (CI) value for the R-PLA-Q composite was lower than for the reference sample. The obtained composite structures may be a good alternative to traditionally used systems as seat elements in rail vehicles, which are not only characterized by high aging resistance but are also more eco-friendly.

3D printing of personalised stents using new advanced photopolymerizable resins and Ti-6Al-4V alloy

PurposeThe development of new advanced materials, such as photopolymerizable resins for use in stereolithography (SLA) and Ti6Al4V manufacture via selective laser melting (SLM) processes, have gained significant attention in recent years. Their accuracy, multi-material capability and application in novel fields, such as implantology, biomedical, aviation and energy industries, underscore the growing importance of these materials. The purpose of this study is oriented toward the application of new advanced materials in stent manufacturing realized by 3D printing technologies.Design/methodology/approachThe methodology for designing personalized medical devices, implies computed tomography (CT) or magnetic resonance (MR) techniques. By realizing segmentation, reverse engineering and deriving a 3D model of a blood vessel, a subsequent stent design is achieved. The tessellation process and 3D printing methods can then be used to produce these parts. In this context, the SLA technology, in close correlation with the new types of developed resins, has brought significant evolution, as demonstrated through the analyses that are realized in the research presented in this study. This study undertakes a comprehensive approach, establishing experimentally the characteristics of two new types of photopolymerizable resins (both undoped and doped with micro-ceramic powders), remarking their great accuracy for 3D modeling in die-casting techniques, especially in the production process of customized stents.FindingsA series of analyses were conducted, including scanning electron microscopy, energy-dispersive X-ray spectroscopy, mapping and roughness tests. Additionally, the structural integrity and molecular bonding of these resins were assessed by Fourier-transform infrared spectroscopy–attenuated total reflectance analysis. The research also explored the possibilities of using metallic alloys for producing the stents, comparing the direct manufacturing methods of stents’ struts by SLM technology using Ti6Al4V with stent models made from photopolymerizable resins using SLA. Furthermore, computer-aided engineering (CAE) simulations for two different stent struts were carried out, providing insights into the potential of using these materials and methods for realizing the production of stents.Originality/valueThis study covers advancements in materials and additive manufacturing methods but also approaches the use of CAE analysis, introducing in this way novel elements to the domain of customized stent manufacturing. The emerging applications of these resins, along with metallic alloys and 3D printing technologies, have brought significant contributions to the biomedical domain, as emphasized in this study. This study concludes by highlighting the current challenges and future research directions in the use of photopolymerizable resins and biocompatible metallic alloys, while also emphasizing the integration of artificial intelligence in the design process of customized stents by taking into consideration the 3D printing technologies that are used for producing these stents.

Carbons derived from resole-type phenolic resins for use in lithium–sulfur batteries: templating the resins with sulfur leads to enhanced cell performance

Pyrolysed resole-type phenol-formaldehyde resins were used as carbonaceous sulfur-hosts in the cathodes of lithium–sulfur batteries.

Development and evaluation of boron carbide-modified unsaturated polyester resin for use as neutron radiation Protection

Neutrons are electrically neutral particles that can penetrate through various materials and interact with atomic nuclei. Neutrons can emit radiation with varying degrees of energy, which can be harmful to both living organisms and the environment. The objective of this study is to evaluate the thermal neutron (0.025 eV) shielding properties of unsaturated polyester resin with boron carbide content ranging from 0 to 20 wt% for use as neutron shielding materials. The FLUKA Monte Carlo simulation was utilized to evaluate the interactions between thermal neutrons and materials with a thickness of 5 cm. The total cross-section, mean free path, and half-value thickness were calculated to assess the shielding properties of materials. The results indicated that as the boron carbide content increased, the total cross-section increased while the mean free path and half-value thickness decreased. In addition, the polyester resin with 20 wt% of boron carbide exhibited the best properties for shielding thermal neutrons. Thus, this study suggests that unsaturated polyester resin containing boron carbide can be used as an effective material for shielding thermal neutrons.

Evaluation of antifungal activity of vanilla pods silver nanoparticles against various oral candidal species: An in-vitro study.

The oral health of individuals is undoubtedly affected by the fact that fungal microorganisms are currently resistant to the conventional antifungal drugs used. Still, there are numerous emerging therapeutic alternatives available like phytotherapy. The phytochemistry of various plant species has indicated that phytochemicals could be a better source of medicine with outstanding antifungal, healing, anti-inflammatory spectrum, and antioxidant properties. To evaluate the antifungal efficacy of silver nanoparticles of vanilla pods against Candida albicans, Candida glabrata, and Candida krusei and to compare with Fluconazole. The vanilla pods were procured from the organic store. The aqueous extracts were prepared. Ten percent of the vanilla extract was utilized to generate the silver nanoparticles. The generated silver nanoparticles were characterized visually based on color change and confirmed by UV spectroscopy. Disk diffusion method was used to determine the antifungal activity of the vanilla pods reinforced silver nanoparticles at different concentrations (20 μl, 40 μ, 40n μ, and 80 μand 80ratioC. albicans, C. glabrata, and C. krusei. The antifungal efficacy of the produced nanoparticles was evaluated against a standard of ketoconazole (30 μ30. Vanillin silver nanoparticles exhibit commendable antifungal activity against C. albicans, C. glabrata which is equivalent to that of ketoconazole, and amplified activity against drug-resistant C. krusei was evident. Silver nanoparticles from vanilla pods were studied and their wider zones of inhibition indicated exemplary antifungal efficacy compared with conventional antifungal drugs like ketoconazole. Future research on vanillin nanocarrier systems might enhance their stability, bioavailability, and bioactivity. As an outcome, with some promising advances in this area, it would be captivating to pursue a systematic investigation into the potential effects of vanillin at the cellular and molecular levels. This will enable us to further assess its applicability as an active biopharmaceutical ingredient in mouthwashes, probiotic lozenges, and denture resin for use as an effective strategy against the biofilm growth of various Candida species.

PLATech overview -radiation-heat tailored VOC-free, bio-renewable polylactic acid polymer formulations & methods for multiple industrial adhesion applications

This paper presents an overview of research and results about tailoring crystalline and amorphous form polylactic acid (PLA) polymer resin for use as an adhesive for joining a range of substrates, production of wood-based composites plywood and particle wood-based composites, and, for potential use for elevated temperature applications as for wood structures when subject to fires. The range of substrates successfully joined (with and without bio-plasticizer) ranges from metals, woods, glasses, ceramics, stones, and bricks to synthetic fluoro-polymers. Tensile bond strength for steel-to-steel bonding ranged towards 40+ MPa; superior (over 100%) bonding strength was obtained compared with EVA and other standard adhesives for wood and metal surfaces. Three successful industrial product arenas are described: 3-ply composite plywood panels meeting water soak and shear strength industry metrics; particle boards meeting-exceeding rupture strength, elasticity, and water resistance metrics similar to those expected from urea-formaldehyde based adhesive but without VOC release limitation, PVC-free luxury flooring tiles which meet strict requirements for wear cycles, distortion-free adhesion peel strength; and, production of renewable particle boards with elastic modulus and internal bond strengths comparable with boards made with urea formaldehyde. Thermal and gamma ionizing radiation research results are discussed to tailor key adhesive-relation properties: adhesion strength, viscosity, flow rate, molecular weight, hardness, flexibility, and friability. Scoping studies on radiation-based tailoring with a cross-linking agent were found to permit up to 30% improvements in bond strength as well as for enabling application as an adhesive for elevated (100 °C+) temperature applications with ∼30–50% higher operating temperatures compared with commonly used adhesives. A discussion is included about the remaining challenges and recommendations for further research.

Optimization of a High Internal Phase Emulsion-Based Resin for Use in Commercial Vat Photopolymerization Additive Manufacturing.

High internal phase emulsions (HIPEs) are potential stereolithography-based resins for producing innovative lightweight porous materials; however, the use of these resins has only been shown in bespoke stereolithography setups. These studies indicated that HIPEs tend to scatter the light during structuring through stereolithography, and can produce poorly defined and low-resolution structures, but the inclusion of light absorbers can drastically increase the printing resolution. In this study, we focused on the inclusion of biocompatible light absorbers within the resin and the compatibility of those resins with a commercial vat photopolymerization additive manufacturing (or stereolithography) setup. A surfactant (hypermer)-stabilized water-in-oil emulsion based on 2-ethylhexyl-acrylate and isobornyl-acrylate was used. For the light absorbers, both hydrophobic (beta-carotene) and hydrophilic (tartrazine) molecules were used, which dissolve in the organic phase and aqueous phase, respectively. It was found that using a combination of both beta-carotene and tartrazine provided the best stereolithography-based 3D printing resolution. In addition, the emulsion was stable for the duration of the printing process and showed a porous polyHIPE structure with open surface porosity. The formulation of these HIPE-based resins permits them to be used in a wide range of applications since complex structures could be fabricated from HIPEs.

Facile synthesis of intrinsically flame‐retardant epoxy thermosets with high mechanical properties from lignin derivatives

AbstractPreparing bio‐based epoxy resins with high performance is crucial to sustainable development. However, seeking renewable and flame‐retardant epoxy resins with high mechanical properties are still challenging. Here, we reported a facile way to transform lignin derivatives to intrinsic flame‐retardant epoxy resins with satisfactory mechanical properties. Two guaiacol‐based novolac epoxy resins (i.e., GTEP/DDM and GPEP/DDM) were prepared as alternatives for petroleum‐based DGEBA/DDM. The cured GTEP/DDM product showed a high Tg of 209.5°C, a high tensile modulus of 3.13 GPa, and a high LOI of 28.6% with UL‐94 V‐1 rating, which outperformed DGEBA/DDM system. Specially, GPEP/DDM resin possessed more superior mechanical properties (e.g., tensile strength of 73.9 MPa, and tensile modulus of 5.85 GPa) owing to additional interactions (i.e., π–π interactions and hydrogen bonds), and outstanding anti‐flammability (e.g., LOI of 31.2% with UL‐94 V‐0 rating) due to the endow of phosphorus‐containing groups. The mechanical reinforcement and flame‐retardant mechanisms were clarified based on structural evolution and performance variation. This work provides an efficient synthesis route to achieve a high‐performance thermoset, which is a promising alternative for substituting conventional bisphenol‐A epoxy resin for use as fireproof materials.

Generation of nucleotide-linked resins for identification of novel binding proteins.

Organisms use numerous nucleotide-containing compounds as intracellular signals to control behavior. Identifying the biomolecules responsible to sensing and responding to changes in signaling molecule concentration is an important area of research. However, identifying the binding proteins can be challenging when there is no prior information available about binding motifs. In this chapter, we describe a straightforward method to generate nucleotide-linked resins for use in pull-down experiments to identify binding proteins. The protocol outlined in this chapter also can be adapted to generate custom resins linked to other molecules of interest.

Volatile Compound Emissions from Stereolithography Three-Dimensional Printed Cured Resin Models for Biomedical Applications.

Stereolithography three-dimensional printing is used increasingly in biomedical applications to create components for use in healthcare and therapy. The exposure of patients to volatile organic compounds (VOCs) emitted from cured resins represents an element of concern in such applications. Here, we investigate the biocompatibility in relation to inhalation exposure of volatile emissions of three different cured commercial resins for use in printing a mouthpiece adapter for sampling exhaled breath. VOC emission rates were estimated based on direct analysis using a microchamber/thermal extractor coupled to a proton transfer reaction-mass spectrometer. Complementary analyses using comprehensive gas chromatography-mass spectrometry aided compound identification. Major VOCs emitted from the cured resins were associated with polymerization agents, additives, and postprocessing procedures and included alcohols, aldehydes, ketones, hydrocarbons, esters, and terpenes. Total VOC emissions from cubes printed using the general-purpose resin were approximately an order of magnitude higher than those of the cubes printed using resins dedicated to biomedical applications at the respective test temperatures (40 and 25 °C). Daily inhalation exposures were estimated and compared with daily tolerable intake levels or standard thresholds of toxicological concerns. The two resins intended for biomedical applications were deemed suitable for fabricating an adapter mouthpiece for use in breath research. The general-purpose resin was unsuitable, with daily inhalation exposures for breath sampling applications at 40 °C estimated at 310 μg day-1 for propylene glycol (tolerable intake (TI) limit of 190 μg day-1) and 1254 μg day-1 for methyl acrylate (TI of 43 μg day-1).

Application of infrared spectroscopy methods in studying compositions for paper sizing

The paper proposes a method of infrared spectroscopy for objective control of the adhesive composition in the production of paper. For sizing paper, in order to increase mechanical strength and reduce water absorption, water-repellent materials are used. One of the most effective and used water-repellent material is ordinary pine resin rosin which is in short supply for the Republic of Uzbekistan. The paper investigates the properties of a new adhesive based on rosin from cherry resin for use in mass sizing in order to expand the range of sizing agents and reduce the share of imported components in the structure of local paper production. Infrared spectroscopy was used to identify the rosin-based glue from the resin of the cherry tree. The built-in device with a diamond crystal of the universal and compact Thermo Scientific Nicolet iS50 IR Fourier spectrometer made it possible to register spectra in the mid and far IR ranges up to 100 cm–1. The efficiency of sizing paper samples was studied by standard methods and evaluated by the following properties: density, tensile strength at stretching on a tensile machine, surface absorbency with one-sided wetting. Infrared spectra revealed the identity of the sizing agent from the resin of the cherry tree to the glue from the pine resin, taken for comparison, because their chemical composition is the same. A comparative analysis of the mechanical and surface properties of paper samples confirmed the possibility of using the studied sizing agent, since the obtained values are close to each other, while it is advisable to add in the range from 1 to 1.5 g per 100 g of dry cellulose raw materials. The use of infrared spectroscopy for express analysis of the composition of the sizing agent is promising, since it becomes possible to control the technological process and create glued types of paper products with desired properties that ensure print quality without loss of fine image details.

3D printed cannulas for use in laparoscopic surgery in feline patients: A cadaveric study and case series.

To evaluate custom 3D printed laparoscopic cannulas (3DPC) in a feline cadaveric abdominal surgery model and report their use in two live feline subjects. Experimental cadaver study, live subject case series. Ten feline cadavers; two feline subjects. Custom 3DPCs were initially modeled in a PLA filament material and then created in an autoclavable dental resin for use in live patients. The surgery time, number of surgical collisions and cannula complications were recorded during cadaver procedures before and after use of 3DPCs. Cannula complications were recorded during live procedures and patients were followed to suture removal to record any incisional complications. There was a significant reduction in mean surgical time (125.6vs. 95.2min, p=0.03), mean number of instrument collisions (6.8 vs. 2.6, p=0.03), and mean number of cannula complications (10 vs. 2.2, p=0.03) with the use of only 3DPCs during the procedure. During the live procedures the use of the 3DPCs was successful and no postoperative complications occurred at the incision sites. The use of customized 3DPCs may improve surgical dexterity and decrease complications in advanced procedures and was not associated with any clinical complications in two cats. The use of 3DPCs in veterinary medicine may allow for wider practice of laparoscopic techniques in small animals.

Preparation and Application of Coumarone-Indene-Carbazole Resin as a Modifier of Road Petroleum Bitumen. 1. Influence of Carbazole:Raw Materials Ratio

The possibility of effectively using carbazole as an improver of coumarone-indene resin for use as a modifier of petroleum bitumens is studied. All starting materials for the production of coumarone-indene-carbazole resin (CICR) were obtained from various products of the coal coking process. The influence of raw material composition (amount of carbazole added to an industrial indene-coumarone fraction) on resin yield and its modifying properties was studied. The optimal amounts of carbazole in the raw material were established, and it is recommended to use CICR as an adhesive additive to bitumen.

Speciality commercial ion exchange resins for use in nuclear industries for antimony removal: A systematic study

Antimony, a metalloid, is present in effluents generated in diverse industries. Antimony is of high concern in nuclear industries in particular due to the presence of its active isotopes. Safe management of such antimony containing effluents is a crucial problem which currently lacks viable solution. One of the reasons is the lack of availability of well-studied antimony removal agents. In this context, three commercially available speciality ion exchange resins (Tulsion® CH-87, CH-90 and CH-99) were evaluated for their antimony removal ability. Among the three resins evaluated, Tulsion® CH-99, a polyhydroxy amine-based resin, showed favourable results and its antimony binding properties were studied in detail. Tulsion® CH-99 showed fast uptake kinetics, selectivity, and antimony removal under wide solution pH conditions. Saturation capacities obtained were found to be 83 mg.g−1 (0.68 mmol.g−1) for Sb(V) and 73.1 mg.g−1 (0.6 mmol.g−1) for Sb(III). Batch and column studies carried out with simulated decontamination and reprocessing effluents of nuclear industry showed selective antimony uptake. Antimony uptake from typical reprocessing effluent (referred to as High Level Waste (HLW)), which has highly acidic and complex matrix (3 M HNO3 and a suite of competing ions such as Cr(VI)), demonstrated the high stability and antimony selectivity of the investigated resin.

Improving UV Curing in Organosolv Lignin-Containing Photopolymers for Stereolithography by Reduction and Acylation.

Despite recent successes in incorporating lignin into photoactive resins, lignin photo-properties can be detrimental to its application in UV-curable photopolymers, especially in specialized engineered resins for use in stereolithography printing. We report on chemical modification techniques employed to reduce UV absorption by lignin and the resulting mechanical, thermal, and cure properties of these modified lignin materials. Lignin was modified using reduction and acylation reactions and incorporated into a 3D printable resin formulation. UV–Vis absorption at the 3D printing range of 405 nm was reduced in all modified lignins compared to the unmodified sample by 25% to ≥ 60%. Resins made with the modified lignins showed an increase in stiffness and strength with lower thermal stability. Studying these techniques is an important step in developing lignin for use in UV-curing applications and further the effort to valorize lignin towards commercial use.

Ion-imprinted resin for use in an automated solid phase extraction system for determining 90Sr in environmental and human samples

In 90Sr analysis, determining its daughter 90Y improves the sensitivity of the radiometric methods. We found that to imprint a cavity made of [Y(6-(4-Vinylphenylcarbamoyl)pyridine-2-carboxylate)3] into a polystyrene skeleton yields a solid phase extraction resin with high selectivity for Y and Ln(III) over transition metals, alkaline, and alkaline-earth cations. We used this resin in an automated chromatography system to extract 90Y from milk, grass, vegetables, soil, sediments, water, human bones, and milk teeth samples. We found that the ion-imprinted resin could be used to separate light Ln(III) using a pH gradient, favoring the targeting of molecules used in nuclear medicine.