Resin Blends Research Articles

Synthesis of an alkynyl‐ and allyla‐ terminated modifiers and its thermal and mechanical properties in copolymer with epoxy resin

AbstractIn this work, this study aimed to overcome the inherent disadvantage of low thermal stability and brittleness of epoxy resins. A novel modifiers containing alkynyl‐ and allyla‐ groups, (E)‐1‐(4‐(allyloxy)‐3‐methoxyphenyl)‐N‐(3‐ethynylphenyl)methanimine (MNEM) was prepared and confirmed by Fourier transform infrared spectroscopy (FTIR) and 1H‐nuclear magnetic resonance (1H NMR), and selected to improve the thermal stability and toughness of bisphenol A‐type epoxy resin (E51). The blend resins were produced by blending with different contents of MNEM into E51 resin, named E‐MNEM resins. Meanwhile, the thermal stability, mechanical properties, and micromorphology of E‐MNEM blends were analyzed in details. It was found that the thermal stability of E‐MNEM resins was improved by increasing the proportion of MNEM. Compared with E‐0MNEM resin, when the MNEM concentration reached 40 wt%, the char yield (Yc) increased from 14.95 to 29.62%, reflecting a 98.1% improvement. In addition, an appropriate concentration of MNEM could be conductive to improving the mechanical properties. An improvement of 25.5 and 7.1% in elongation and tensile strength along with the maximum value of 17.6 kJ/m2 for the impact strength was achieved by the cured E‐MNEM resins containing 20 wt% of MNEM. Finally, the fracture surface morphology of the E‐MNEM resins was analyzed by the scanning electron microscope (SEM).

Elemental Analysis of Tetragonula laeviceps Propolis by X-Ray Fluorescence Spectroscopy

Propolis, a natural substance produced by stingless bees (Tetragonula laeviceps), consists of a blend of resins collected from plant exudates and other botanical sources. Bees utilize propolis for hive maintenance and protection against predators. Propolis is widely used in various therapeutic formulations, including treatments for upper respiratory tract infections, burns, acne, herpes, and neurodermatitis. The propolis samples were analyzed using Olympus DELTA Professional Handheld XRF Analyzer. This study employs X-Ray Fluorescence (XRF) analysis to investigate the elemental composition of propolis. Data results of XRF were presented in percentage with limit detection into ppm (%, ppm). The result showed that the three most dominant elements composition in propolis sample from FB 1 were Ca(77.12%) ; K(11.59%), and SO3(5.18%). Propolis Sample from KP 1 were Fe(31.73%);Ca (26.42%); and K(14.04%). Propolis Sample from KP 2 were K(28.32%); P2O5(24.35%); and Ca(18.82%). The conclusion was that the three propolis samples contained 2 constant elements, namely Calcium (Ca) and Potassium (K). Calcium and Potassium were found to be essential functions in all organisms.

An economic and environmental assessment of guayule resin co-products for a US natural rubber industry

Guayule (Parthenium argentatum) is a natural rubber producing desert shrub that has the potential to be grown in semi-arid areas with limited water resources. Numerous studies have examined the costs and environmental impacts associated with guayule rubber production. These studies identified the need for additional value from the rubber co-products, specifically the resin, for sustainable and commercial viability of the biorefinery concept. This study developed process models for resin-based monoterpenes, insect repellant, and adhesive co-products that are integrated with sustainability assessments to understand the commercial viability. A techno-economic analysis and cradle-to-gate life cycle assessment of these three different co-product pathways assumed a facility processing 66 tonnes/day of resin (derived from the processing of 1428 tonnes per day of guayule biomass) and included resin separation through co-product formation. Additionally, a fourth pathway was evaluated, combining the insect repellent and monoterpene process models to evaluate potential advantages resulting from their integration. The evaluation outcomes were integrated into an established guayule rubber production model to assess the economic potential and environmental impact of the proposed guayule resin conversion concepts. The minimum selling price for rubber varied by co-product: $3.64 per kg for monoterpenes, $3.48 per kg for insect repellent, and $1.90 per kg for resin blend adhesive. The resin blend adhesive co-product pathway had the lowest greenhouse gas emissions. These findings show a pathway that supports the development of a biorefining concept based on resin-based adhesives that can catalyze a US based natural rubber industry.

Low cost structured photocatalysts from stereolithography of colorless pharmaceutical glass

The present study is dedicated to the manufacturing of highly porous triply periodic minimal surface (TPMS) constructs, fabricated from recycled end of life borosilicate pharmaceutical glass employing masked stereolithography. The structures were prepared from a simple blend of photocurable resin with glass powder (<38 µm). The gyroid model was selected with the porosity varying from 75 to 90%. Hot stage microscopy was applied to examine the glass sintering behaviour to improve the translucency of the 3D scaffolds. The obtained 3D scaffolds were dip-coated with TiO2 and further utilized for the photocatalytic degradation of dyes. The photocatalytic efficiency of the 3D scaffolds was evaluated by the degradation of methylene blue in water. It was found that 3D scaffolds coated with TiO2 showed a 40% higher degradation rate in comparison to bare 3D scaffolds under UV irradiation, which determines the significant role of TiO2 in the organic dye degradation. The better efficiency of 3D scaffolds coated with TiO2, compared with uncoated BSG 3D scaffolds is attributed to a better recombination rate, and the migration of electrons to the surface of the scaffold, where the charges participate in the photodecomposition of MB dye. The efficiency of the scaffolds was assessed for five consecutive cycles. The degradation efficiency after the fifth cycle was 75%, confirming the stability of the system.

Non-destructive evaluation of the curing of a polybenzoxazine nanocomposite blend for space applications using fluorescence spectroscopy and predictive mechanical modelling

In this study, we employ fluorescence spectroscopy to monitor the curing process of a novel polybenzoxazine (PBZ) resin blend containing a polyhedral oligomeric silsesquioxane (POSS) reagent in a non-destructive way and compare it with the differential scanning calorimetry data. Our resin blend has been carefully selected for study on the International Space Station in 2024 as part of the Euro Materials Ageing 1 Programme (AO-2020-EMA) supported by the European Space Agency (ESA) and the French Space Agency (CNES). Computational simulations of PBZ-POSS blend composites are investigated to determine their effective mechanical responses based on constituent micro-stresses with periodic boundary conditions and continuum-based analytical micromechanical models. Further investigations are focused on the development of different representative volume element models, including periodic, non-periodic, and overlap inclusions, and the comparison with experimental data. Fluorescence spectroscopy and computational and analytical methods can offer a non-destructive approach to gaining insights into polymerisation processes and effective mechanical responses.

Preparation and properties of alcohol‐resistant thermal transfer printing inks for multifunctional label printing via physical blending of resins

AbstractDue to the rise of the logistics industry and the widespread use of ink labels, problems such as the narrow operating temperature range of ink, poor alcohol resistance, and insufficient scratch resistance need to be solved urgently. In this work, creates alcohol‐resistant thermal transfer inks by mixing polypropylene chloride (VP‐365) and epoxidized hydrogenated bisphenol A (P) resin and incorporating them into the ink formulation. The synthetic ink has a lower glass transition temperature (118.2°C), allowing the ink to print at lower temperatures. It has small wetting angles (68°, 63°, 58°, 46°, and 40°) and a large adhesion force (10.44 – 14.4 N) for different labels. Further, to evaluate the printing performance of the ink, the ink was scratched under 1000 g pressure and in the environment of isopropyl alcohol to evaluate its printing performance. The produced ink has high scratch resistance (300 times) and good alcohol resistance (140 times). Moreover, the developed ink showed good printability, printing media versatility, high adhesion, and excellent alcohol resistance. The synthesis method is facile and cost‐effective, which paves a novel way towards high‐performance ink printing and thermal transfer technology industries.

Synthesis and characterization of alkyd resins from rubber seed/soybean oil blends

The polymerization and properties of environmentally friendly resin binders applicable in the surface-coating industry were studied. Rubber seed oil (RSO) and RSO blended with 10% and 20% soybean oil (SBO)-based alkyd resins were synthesized by alcoholysis- polyesterification of the oil with glycerol and phthalic anhydride. Physicochemical properties (such as colour, specific gravity, acid value, saponification value, iodine value, and drying schedule) of the alkyd resins were determined to establish the possible industrial potential of the resins. The saponification value and iodine value ranged from 250.19 mgKOH/g to 279.55 mgKOH/g and 29.58 gI2/100g to 33.77 gI2/100g respectively. The drying schedule and chemical resistance of the blended alkyd resins to water, salts, acids, and alkalis were also studied. The blended resins were found to be resistant to water, salt, and acid media, except for alkali media. The colour properties were enhanced as the percentage of the blend increased. FT-IR spectroscopic study of the oil and alkyd resin samples further corroborates our findings. Therefore, the potential of rubber seed oil blended with soybean oil to produce light-coloured alkyd resins could be exploited as raw materials for the Nigerian surface coating industry.

The Catalytic Curing Reaction and Mechanical Properties of a New Composite Resin Matrix Material for Rocket Fuel Storage Tanks

In this paper, an equimolar blend of bisphenol A dipropargyl ether and cyanate ester was selected to study the effect of different catalysts on the curing reaction of a bisphenol A dipropargyl ether and cyanate ester blended resin system, and the thermal stability and mechanical properties of the catalytically cured blended resin system were investigated. Acetylacetone salts of transition metals and dibutyl ditin laurate reduced the curing temperature of bisphenol AF-type di cyanate ester, and copper acetylacetonate at a mass fraction of 0.3% significantly reduced the curing temperature of bisphenol AF-type di cyanate ester to less than 473 K. Bisphenol A dipropargyl ether pr-polymerized and equimolarly blended with bisphenol A di cyanate ester and bisphenol E-type di cyanate ester also cured below 473 K under the same conditions. Among the cured compounds of the blended resins of bisphenol A dipropargyl ether with bisphenol AF-type di cyanate ester, bisphenol A-type di cyanate ester and bisphenol E-type di cyanate ester, the blended resins of bisphenol A-type di cyanate ester and bisphenol E-type di cyanate ester have better overall performance. The residual rate of 873 K in air was 38%, and the flexural strength, flexural modulus, and impact strength were 129.4 MPa, 4.3 GPa, and 27.3 kJ·m−2, respectively. This kind of blended resin is expected to be used in the liquid oxygen storage tanks of rockets.

Investigation on mechanical properties and thermal expansibility of epoxy resin copolymerization modified cyanate ester under medium‐low temperature curing process

AbstractIn this paper, the mechanical properties and thermal expansibility of cyanate resin (CE) copolymerization modified by epoxy resin (EP) under medium‐low temperature curing process were studied. The curing temperature of the modified resin was analyzed, and the results showed that the initial curing temperature of the copolymerization resin was reduced by 87°C compared with the blend resin and further reduced when dibutyltin‐dilaurate was used. The results of mechanical properties test showed that the tensile and bending strength of the modified resin were the highest, which were 55.5 and 97.3 MPa, respectively. The results of scanning electron microscopy showed that the modified resin with 80 wt% cyanate content had the coarsest tensile and bending sections, the largest number of fracture stripes and rich layers, so it had relatively better toughness. The linear thermal expansion coefficient (CTE) of modified resin was determined and the results showed that when the loading of cyanate was 80 wt%, the CTE of the modified resin reached the lowest, only 6.36 × 10−5°C−1.

In Vitro Investigation of the Mechanical Properties of Blended 3D-Printing Resins for Orthodontic Aligners: A Comparison between Commercial Resin and Nickel-Titanium Wire

This scientific article investigates the mechanical properties of a novel three-dimensional-printing resin specifically designed for orthodontic aligners and compares it to other commonly used resins. The resin was made by blending two commercially available and certified resins to produce aligners with improved mechanical properties compared to each separate resin. The study examined the effect of the addition of NextDent Ortho Rigid resin on the mechanical properties of the specimens, more specifically analyzing the relationship between the amount of the added rigid resin and the mechanical properties of the specimens. The mechanical properties of the specimens and the nickel-titanium wires were analyzed using a three-point bending test setup. The results showed no statistically significant differences within the different groups of specimens. The study provides valuable insights into the potential of the resin to meet the mechanical demands of orthodontic treatments. It will contribute to the advancement of personalized orthodontic care through three-dimensional-printing technology. Blending commercially available and certified resins enables orthodontic practitioners to select the most suitable resin for each case, providing better outcomes for patients and increasing the efficiency of the treatment process. Further research and evaluation would be required to determine the suitability of the blended resin for orthodontic treatments.

Study on Blending Modification of Bisphenol A Epoxy.

Epoxy-resin-based composites in the field of current electrical materials often work in high temperature, high humidity or salt spray conditions. In order to improve the operation reliability of the composite insulator cross arm in a high temperature, high humidity and high salt spray environment, and analyze the aging mechanism and performance characteristics of resin, in this paper, wet heat aging and salt spray aging experiments were carried out on the blended resin system composed of bisphenol A type epoxy resin (E-51), aliphatic epoxy modified bisphenol A epoxy resin (2021P/E-51) and dimeric acid modified bisphenol A epoxy resin (EPD-172/E-51). Among them, 10 wt% and 20 wt% of 2021P blend resin and 10 wt% of EPD blend resin have superior thermo-mechanical properties. Under humid and hot conditions, the dielectric loss of 10 wt% EPD blend system before and after aging is 39.9% and 49.5% lower than that of pure E51 resin system, respectively. Under the condition of salt spray, the dielectric loss of 20 wt% and 10 wt% EPD blends decreased by 73.1% and 74.6% after aging. The leakage current of 10 wt% 2021P blend resin and 10 wt% EPD blend resin decreased by 7% and 3.8% before aging, respectively. After aging, they decreased by 3.7% and 2.2%, respectively. The bending strength of 2021P blend resin before and after aging reached 29.3 MPa and 26.6 MPa, respectively. The above three blending resin systems exhibit good electrical properties and good mechanical properties, their ageing resistance performance is strong and they are suitable as the matrix resin of compound cross arm mandrel material.

Characterization of Eumelanin as an Additive in High‐Temperature Phthalonitrile‐Based Resin Blends

AbstractBio‐manufactured eumelanin is investigated as a sustainable high‐char carbon additive for use with moldable high temperature resins. Blends of Bisphenol A poly‐ether‐ether‐ketone (PEEK)‐based phthalonitrile (PN) with 0–30 wt% melanin are prepared and characterized for their compositional, thermal, and mechanical properties. Although the char yield increases from 10 to 30 wt% melanin loading, the presence of melanin decreases the thermal stability compared to PN resin alone. Despite this, the melanin‐PN resins still maintain a very high char yield (&gt;64%) up to 1000 °C under nitrogen. Rheology, thermal analysis, and mechanical measurements suggest off‐gassing of the melanin and increased crosslinking between the melanin and PN, leading to a lower flexural strength resin with higher additive loadings. Spectroscopic studies suggest possible interaction between melanin and PN during co‐curing, which ultimately can affect the processing and final properties of melanin‐additive composite materials.

A resin adhesive with balanced antibacterial and mineralization properties for improved dental restoration

ObjectiveAiming to develop an adhesive formulation that achieves a harmonious equilibrium between antibacterial efficacy and mineralization potential, 2-methacryloyloxy ethyl phosphorylcholine (MPC), N,N-dodecylvinylimidazole (DCV), and Sr-doped hydroxyapatite (Sr/HAp) nanorods were incorporated as functional constituents into the adhesive matrix, employing carefully optimized proportions. MethodsThe adhesive formulation comprised a blend of bisphenol A glycerolate dimethacrylate (Bis-GMA), 2-hydroxyethyl methacrylate (HEMA), and 1,6-hexanediol dimethacrylate (HDDMA) monomers. The effects of MPC and DCV additions, ranging from 1% to 4% (wt%), on various aspects such as adhesive curing kinetics, bonding strength, water contact angle, mechanical properties, and antibacterial activities against Streptococcus mutans (S. mutans) and Human Saliva Bacterial Flora (HSBF), was investigated both individually and in combination. Following the determination of the optimized MPC/DCV ratio, the effect of Sr/HAp on the mineralization potential of the adhesives was evaluated by soaking the samples in 1.5 times simulated body fluid (SBF) at 37 °C for 3 days followed by examination using scanning electron microscopy (SEM). Additionally, biocompatibility assay was conducted using L929 fibroblasts. ResultsThe introduction of MPC and DCV did not interfere the CC conversion degree of the resin blends in all the preparations. Notably, the incorporation of 3 wt% MPC demonstrated a significantly enhancement in the hydrophilicity of the adhesive, resulting in reduced bacterial adsorption. The addition of 3 wt% DCV exhibited potent antibacterial properties against attached bacteria. Furthermore, the introduction of 8 wt% Sr/HAp displayed a positive effect on mineral deposition on the adhesive surface. Importantly, all adhesive formulations demonstrated negligible cytotoxicity. Although a decrease in bonding strength was observed upon the introduction of MPC/DCV, the supplementation of Sr/HAp exhibited a reinforcing effect, effectively compensating for the decline. This beneficial outcome can be attributed to a substantial improvement in the flexural strength/modulus of the composite adhesive. SignificanceThe adhesive, simultaneously having ability in inhibiting bacteria adsorption, killing bacteria and promoted mineralization, holds great potential in achieving strong bonding strength for dental restoration applications to minimize repair failure.

Omniphobic coatings based on functional acrylic polymer

Omniphobic coatings were prepared on flat surfaces using a functional acrylic polymer and common micron sized inorganic particles by a simple spray application technique. This coating comprises of a blend of functional acrylic polysiloxane polymer and liquid epoxy resin as a primer base coat followed by spray application of a mixture of organosilanes and inorganic microparticles. The microparticles are fillers commonly used in the paint and coating industry. The resulting surface has the desired surface energy and surface morphology to enable liquid repellency with contact angles of ∼150° for water and 142° for diiodomethane with a roll off angle of <5°. Scanning Electron Microscopic (SEM) and Atomic Force Microscopy (AFM) analysis were performed to study surface morphology. This coating can be applied on large areas and can be cured under ambient conditions. This omniphobic coating is robust, free of nanoparticles and can be used for potential applications in the field of self-cleaning coatings, anti-microbial coatings, and easy cleaning coatings.

High‐temperature resistance and excellent electrical insulation in epoxy resin blends

AbstractThe packaging insulation material was a crucial component to guarantee the stable and safe operation of electronic devices. Epoxy resin, one of the most popular packaging materials, was widely used as an electronic packaging material because of its good corrosion resistance and electrical insulation, low price, and easy processing and molding. However, the unsatisfied heat resistance cannot meet the requirements of the rapid development of third‐generation power semiconductors, so it was meaningful to modify the epoxy resin with both excellent heat resistance and insulation. In this paper, tetrafunctional epoxy resin AG70 and phenolic epoxy resin F51 was blended in different proportions to combine their individual advantages, and the microstructure and electrical/thermal properties of epoxy resin blends had been systematically studied. The results showed that with the increase of blending ratio of AG70 with F51, both high glass transition temperature of 213.3°C and electric breakdown of 206.1 kV/mm were achieved when the blending ratio was 5:5, displaying excellent overall performances and exhibiting great application potential in electronic and microelectronic industries.

Enhancing the comprehensive performance of bisphenol A epoxy resin via blending with a bio-based counterpart

Modification of epoxy resins has emerged as a growing trend but also presents significant challenges, as it is difficult to trade off various properties, for example, improving the toughness of the resin often sacrifices its thermal stability and flame retardancy. In this study, a bio-based tetra-functional epoxy precursor (MTEP) derived from magnolol was blended to comprehensively improve the performances of the commonly used petroleum-based bisphenol A epoxy precursor (E51) with 4,4′-diaminodiphenyl sulfone (DDS) as curing agent, and the thermal stability, mechanical properties and flame retardancy of the blended systems were evaluated. The results showed that the MTEP/E51/DDS blend resin exhibited maximum impact strength (37.8 MPa), representing a 54.3% improvement over E51/DDS (24.5 MPa). The addition of 50 wt% of MTEP into E51/DDS increased the flexural modulus up to 3281 MPa (by ∼23.6%), in combination with appreciable increases in the glass transition temperature (by 50 °C) and intrinsically flame retardancy in UL-94 test (from NR to V-0). The above results prove that it is feasible to improve the performances of petroleum-based epoxy resin with high-performance bio-based counterpart, which is often the opposite before, which also provides a novel approach for the modification of epoxy resin.

Bismaleimide resins modified by a novel vanillin‐derived allyl compounds: Synthesis, curing behavior, and thermal properties

AbstractIn this study, a novel biobased allyl compound with Schiff‐based structure (MPAM) was developed to improve the toughness and thermal properties of 4,4′‐bismaleimidodiphenylmethane (BDM). The chemical structure of MPAM was characterized by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (1H NMR). A series of BDM/DBA‐MPAM blend resins (BD‐MPAM resins) were prepared by adjusting the mass ratio of BDM + DBA (BD) to MPAM. The effects of MPAM content on the curing behavior, thermal and mechanical properties of BD‐MPAM resins were discussed in details. Compared with BD resin, the thermal stability of modified resins was improved by increasing the content of MPAM. Meanwhile, an increase of 37.1% in flexural strength, and 228 MPa in flexural modulus were obtained for the cured BD‐MPAM resin having 10 wt% MPAM loading compared to the BD resin. The impact strength of BD‐10 wt% MPAM is of the maximum value (6.6 kJ/m2). Finally, the fracture surface morphology of the BD‐MPAM resins was studied by the scanning electron microscope (SEM).

Sputtering Plasma Effect on Zinc Oxide Thin Films Produced on Photopolymer Substrates.

This work presents a post-cured treatment alternative for photopolymer substrates considering the plasma produced via the sputtering process. The sputtering plasma effect was discussed, analyzing the properties of zinc/zinc oxide (Zn/ZnO) thin films deposited on photopolymer substrates, with and without ultraviolet (UV) treatment as a post-treatment process, after manufacturing. The polymer substrates were produced from a standard Industrial Blend resin and manufactured using stereolithography (SLA) technology. After that, the UV treatment followed the manufacturer's instructions. The influence of the sputtering plasma as an extra treatment during the deposition of the films was analyzed. Characterization was performed to determine the microstructural and adhesion properties of the films. The results showed the effect of plasma as a post-cured treatment alternative: fractures were found in thin films deposited on polymers with previous UV treatment. In the same way, the films showed a repetitive printing pattern due to the phenomenon of polymer shrinkage caused by the sputtering plasma. The plasma treatment also showed an effect on the thicknesses and roughness values of the films. Finally, according to VDI-3198 standards, coatings with acceptable adhesion failures were found. The results provide attractive properties of Zn/ZnO coatings on polymeric substrates produced by additive manufacturing.

High Tg, Bio-Based Isosorbide Methacrylate Resin Systems for Vat Photopolymerization.

The use of isosorbide-derived polymers has garnered significant attention in recent decades as a high-performance, renewable material sourced from biomass. Of particular interest is isosorbide methacrylate, which possesses low viscosity (<500 cps), high thermal properties (Tg ≈ 220 °C), and high modulus (>4 GPa). These characteristics present a promising opportunity to replace BPA-derived methacrylate compounds in various applications. This investigation aims to synthesize and characterize isosorbide-based low-viscosity resin systems for 3D printing. The resin blends are composed of isosorbide methacrylate and two bio-renewable methacrylates, furfuryl methacrylate (FM) and bis-hydroxymethyl-furan methacrylate (BHMF-M), polymerized through a digital light processing (DLP) technique. The addition of the bio-based co-monomers serves to enhance the fracture toughness of the brittle isosorbide methacrylate crosslinked homopolymer (GIc = 37 J/m2). The resulting polymers exhibit Tg values greater than 200 °C and GIc around 100 J/m2. These resin systems hold potential for imparting high bio-based content to polymers used in additive manufacturing for high-performance applications.

Corrosion control by autonomous self-healing epoxy coatings based on superabsorbent healing agents

Metallic corrosion is an all-time dangerous and extremely expensive problem. Here, we present an autonomous self-healing polymer coating based on an epoxy resin and superabsorbent polymer (SAP) blend as an anticorrosion coating. Tailor-made coatings were manufactured by controlling the location of the SAP on the surface, middle, and bottom of the coating. The corrosion behavior and self-healing process of the coatings were analyzed at the macro, micro, and sub-micro scales using Electrochemical Impedance Spectroscopy (EIS). The SAP preferentially located at the bottom showed coating resistance values higher than 1 × 1011 Ωcm2 over 10 days of immersion with 3-point defects. This configuration provided the best anticorrosion performance, preventing coating delamination, and protecting the metal from corrosion after surface damage, indicating better barrier properties. The SAP enabled local repair of the crack when in contact with water, minimizing the diffusion of oxygen and electroactive species, which are responsible for the corrosion of a metal.