Studies on the Curing Efficiency and Mechanical Properties of Bis-GMA and TEGDMA Nanocomposites Containing Silver Nanoparticles

Bioactive dimethacrylate composites filled with silver nanoparticles (AgNP) might be used in medical applications, such as dental restorations and bone cements. The composition of bisphenol A glycerolate dimethacrylate (Bis-GMA) and triethylene glycol dimethacrylate (TEGDMA) mixed in a 60/40 wt% ratio was filled from 25 to 5000 ppm of AgNP. An exponential increase in resin viscosity was observed with an increase in AgNP concentration. Curing was performed by way of photopolymerization, room temperature polymerization, and thermal polymerization. The results showed that the polymerization mode determines the degree of conversion (DC), which governs the ultimate mechanical properties of nanocomposites. Thermal polymerization resulted in a higher DC than photo- and room temperature polymerizations. The DC always decreased as AgNP content increased. Flexural strength, flexural modulus, hardness, and impact strength initially increased, as AgNP concentration increased, and then decreased at higher AgNP loadings. This turning point usually occurred when the DC dropped below 65% and moved toward higher AgNP concentrations, according to the following order of polymerization methods: photopolymerization < room temperature polymerization < thermal polymerization. Water sorption (WS) was also determined. Nanocomposites revealed an average decrease of 16% in WS with respect to the neat polymer. AgNP concentration did not significantly affect WS.

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Monomers used in resin composites: degree of conversion, mechanical properties and water sorption/solubility

Brazilian Dental Journal ◽

10.1590/s0103-64402012000500007 ◽

2012 ◽

Vol 23 (5) ◽

pp. 508-514 ◽

Cited By ~ 119

Author(s):

Vinícius E. S. Gajewski ◽

Carmem S. Pfeifer ◽

Nívea R. G. Fróes-Salgado ◽

Letícia C. C. Boaro ◽

Roberto R. Braga

Keyword(s):

Mechanical Properties ◽

Water Sorption ◽

Flexural Modulus ◽

Triethylene Glycol ◽

Degree Of Conversion ◽

Resin Composites ◽

Triethylene Glycol Dimethacrylate ◽

Three Point Bending ◽

Rate Of Polymerization ◽

Urethane Dimethacrylate

The organic phase of resin composites is constituted by dimethacrylate resins, the most common monomers being the bisphenol A diglycidildimethacrylate (BisGMA), its ethoxylated version (BisEMA), triethylene glycol dimethacrylate (TEGDMA) and urethane dimethacrylate (UDMA). This study compared the homopolymers formed from the monomers used in restorative dental composites in terms of their degree of conversion (DC) and reaction kinetics (by near infra-red spectroscopy, n=3), mechanical properties (flexural modulus and strength in three point-bending, FM and FS, respectively, n=15), water sorption and solubility (WS and SL, respectively - ISO 4049, n=5). Materials were made photopolymerizable by the addition of camphoroquinone/dimethylamine ethyl methacrylate. TEGDMA showed the highest DC, followed by BisEMA, UDMA and BisGMA, both at 10 min and at 24h (p<0.001). UDMA showed the highest rate of polymerization, followed by TEGDMA, BisEMA and BisGMA (H0=13.254, p<0.001). UDMA and TEGDMA presented similar FM, significantly higher (p<0.001) than BisEMA and BisGMA, which in turn present statistically similar values (p>0.001). For FS, UDMA presented the highest value (p<0.001), followed by TEGDMA, then by BisEMA and BisGMA, which were statistically similar (p>0.001). BisGMA showed the highest WS, and TEGDMA and BisEMA the lowest. UDMA was statistically similar to all (H0=16.074, p<0.001). TEGDMA presented the highest SL, followed by UDMA, BisGMA and BisEMA (p<0.001). The tested homopolymers presented different behaviors in terms of polymerization kinetics, flexural properties, water sorption and solubility. Therefore, the use of copolymers is justified in order to obtain high DC and mechanical properties, as well as good resistance to water degradation.

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Synthesis and research of photocurable protective coatings on the basis of olygoesteracrylates

Chimica Techno Acta ◽

10.15826/chimtech.2020.7.4.16 ◽

2020 ◽

Vol 7 (4) ◽

pp. 229-232

Author(s):

O. A. Karsakova ◽

M. V. Kuzmin

Keyword(s):

Mechanical Properties ◽

Polyethylene Glycol ◽

Methacrylic Acid ◽

Protective Coatings ◽

Physical And Mechanical Properties ◽

Triethylene Glycol ◽

Glycol Dimethacrylate ◽

Triethylene Glycol Dimethacrylate ◽

Rotary Viscometer ◽

Acid Esters

In this work, photocurable protective coatings based on methacrylic acid esters have been developed and their physical and mechanical properties have been investigated. The photocurable compositions were obtained by mixing at different ratios the following methacrylic acid esters: polyethylene glycol dimethacrylate 400 and triethylene glycol dimethacrylate ether, polyethylene glycol dimethacrylate 400 and oligourethane dimethacrylate, polyethylene glycol dimethacrylate 400 and pentaerythritol tetraacrylate. For the obtained compositions, the viscosity was studied using a Brookfield rotary viscometer. To initiate polymerization, a mixture of initiators was used: benzoyl peroxide and benzoin. Curing of the obtained compositions was carried out under the influence of UV rays for 2-5 minutes. For photo-cured compositions, their physical and mechanical properties have been studied. It was found that the composition based on polyethylene glycol dimethacrylate modified with triethylene glycol dimethacrylate at a ratio of 70:30 has the highest strength.

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Correlation of Optical and Mechanical Properties of Silver Nanoparticles Sensitized Europium Doped Magnesium Zinc Sulfophosphate Glasses

Science Proceedings Series ◽

10.31580/sps.v2i2.1276 ◽

2020 ◽

Vol 2 (2) ◽

pp. 147-155

Author(s):

Ibrahim Mohammed Danmalam ◽

Ibrahim Bulus

Keyword(s):

Mechanical Properties ◽

Silver Nanoparticles ◽

Vickers Hardness ◽

Room Temperature ◽

Surface Engineering ◽

Glass Composition ◽

Melt Quenching ◽

Optical And Mechanical Properties ◽

Quenching Method ◽

The Relationship

Magnesium-zinc-sulfophosphate glasses with various concentration of Silver nanoparticles (AgNPs) of molar composition 63.5P2O5–20MgO –15ZnSO4–1.5Eu2O3 –yAgNps (y = 0.0, 0.1, 0.3, 0.5, 0.7,0.9 and 1.1 g in excess) were prepared via melt-quenching method. As-synthesized glasses were characterized at room temperature to determine the relationship between structural and mechanical properties. Densities of glasses were increased from 3.0720 to 4.3304 g.cm-3 with increase in AgNPs embedding levels, suggesting the network shrinkages and enhanced compactness. The Young’s, shear and bulk modulus of glasses were observed to enhance with the increase in AgNPs contents. The Poisson’s ratio of the studied glasses was increased from (0.0978 to 0.1416) while the values of both Vickers hardness (from 0.0658 to 0. 0.0682 GPa) as well as (from 0.8350 to 0.8916) were increased. The proposed glass composition may be useful for the development of hard surface engineering.

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Characterization and Mechanical Properties of Epoxidized Palm Oil/Epoxy Resin Blend

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1113.13 ◽

2015 ◽

Vol 1113 ◽

pp. 13-18 ◽

Cited By ~ 1

Author(s):

Zyad Salem Alsagayar ◽

Abdul Razak Rahmat ◽

Agus Arsad ◽

Alireza Fakhari ◽

Amirali Khalili

Keyword(s):

Mechanical Properties ◽

Epoxy Resin ◽

Palm Oil ◽

Room Temperature ◽

Fourier Transforms ◽

Direct Method ◽

Flexural Modulus ◽

Hydroxyl Group ◽

Epoxidized Palm Oil ◽

Fourier Transforms Infrared Spectroscopy

Epoxidized vegetable oils based thermoset materials are widely used to develop biopolymers and to replace the fossil-fuel based polymers. In this paper, a blend of epoxy resin and epoxidized palm oil (EPO) were prepared and characterized by direct and pre-mixed methods to investigate its mechanical properties. For direct method, epoxy and EPO were mixed for 20 minutes at room temperature followed by curing for 2 hours at 100 °C. On other hand, for pre-mixed method, the EPO was reacted with hardener at 120 °C for 1 and 2 hours. Then it was mixed with epoxy resin at room temperature for 20 minutes followed by curing for 2 hours at 100 °C. Fourier transforms infrared spectroscopy [FTIR] and mechanical properties tests were used to characterize the blend. FTIR showed that, a reaction of epoxide group in EPO with active hydrogen atom from hardener and produced a hydroxyl group at 3300 cm-1. In general, the mechanical properties of epoxy resin/EPO were decreased when the amount of EPO was increased. However, at constant amount of EPO Young’s modulus, toughness, flexural strength, and flexural modulus were slightly increased when the time of EPO/hardener was increased. The mechanical properties were reduced due to the reduction of the cross linking density and effect of plasticizer.

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Novel CaF2 Nanocomposites with Antibacterial Function and Fluoride and Calcium Ion Release to Inhibit Oral Biofilm and Protect Teeth

Journal of Functional Biomaterials ◽

10.3390/jfb11030056 ◽

2020 ◽

Vol 11 (3) ◽

pp. 56 ◽

Cited By ~ 3

Author(s):

Heba Mitwalli ◽

Abdulrahman A. Balhaddad ◽

Rashed AlSahafi ◽

Thomas W. Oates ◽

Mary Anne S. Melo ◽

...

Keyword(s):

Mechanical Properties ◽

Calcium Fluoride ◽

Calcium Ion ◽

Triethylene Glycol ◽

Human Saliva ◽

The Novel ◽

Oral Biofilm ◽

Ion Release ◽

Triethylene Glycol Dimethacrylate ◽

Colony Forming Units

(1) Background: The objective of this study was to develop a novel dental nanocomposite containing dimethylaminohexadecyl methacrylate (DMAHDM), 2-methacryloyloxyethyl phosphorylcholine (MPC), and nanoparticles of calcium fluoride (nCaF2) for preventing recurrent caries via antibacterial, protein repellent and fluoride releasing capabilities. (2) Methods: Composites were made by adding 3% MPC, 3% DMAHDM and 15% nCaF2 into bisphenol A glycidyl dimethacrylate (Bis-GMA) and triethylene glycol dimethacrylate (TEGDMA) (denoted BT). Calcium and fluoride ion releases were evaluated. Biofilms of human saliva were assessed. (3) Results: nCaF2+DMAHDM+MPC composite had the lowest biofilm colony forming units (CFU) and the greatest ion release; however, its mechanical properties were lower than commercial control composite (p < 0.05). nCaF2+DMAHDM composite had similarly potent biofilm reduction, with mechanical properties matching commercial control composite (p > 0.05). Fluoride and calcium ion releases from nCaF2+DMAHDM were much more than commercial composite. Biofilm CFU on composite was reduced by 4 logs (n = 9, p < 0.05). Biofilm metabolic activity and lactic acid were also substantially reduced by nCaF2+DMAHDM, compared to commercial control composite (p < 0.05). (4) Conclusions: The novel nanocomposite nCaF2+DMAHDM achieved strong antibacterial and ion release capabilities, without compromising the mechanical properties. This bioactive nanocomposite is promising to reduce biofilm acid production, inhibit recurrent caries, and increase restoration longevity.

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Mechanical Properties and Dislocation Structure of Single Crystal Cdte Deformed in Compression at 300°C

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010009292x ◽

1976 ◽

Vol 34 ◽

pp. 592-593

Author(s):

Ernest L. Hall ◽

J. B. Vander Sande

Keyword(s):

Mechanical Properties ◽

Single Crystal ◽

Dislocation Structure ◽

Room Temperature ◽

Elevated Temperatures ◽

Strain Curve ◽

Optical Devices ◽

Semiconductor Compound ◽

Wide Range ◽

Sample Orientation

The present paper describes research on the mechanical properties and related dislocation structure of CdTe, a II-VI semiconductor compound with a wide range of uses in electrical and optical devices. At room temperature CdTe exhibits little plasticity and at the same time relatively low strength and hardness. The mechanical behavior of CdTe was examined at elevated temperatures with the goal of understanding plastic flow in this material and eventually improving the room temperature properties. Several samples of single crystal CdTe of identical size and crystallographic orientation were deformed in compression at 300°C to various levels of total strain. A resolved shear stress vs. compressive glide strain curve (Figure la) was derived from the results of the tests and the knowledge of the sample orientation.

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Autonomous self-healing polyisoprene elastomers with high modulus and good toughness based on the synergy of dynamic ionic crosslinks and highly disordered crystals

Polymer Chemistry ◽

10.1039/d0py01034k ◽

2020 ◽

Vol 11 (41) ◽

pp. 6549-6558

Author(s):

Yohei Miwa ◽

Mayu Yamada ◽

Yu Shinke ◽

Shoichi Kutsumizu

Keyword(s):

Mechanical Properties ◽

Room Temperature ◽

Self Healing ◽

High Modulus ◽

Disordered Crystals ◽

Ionic Crosslinks

We designed a novel polyisoprene elastomer with high mechanical properties and autonomous self-healing capability at room temperature facilitated by the coexistence of dynamic ionic crosslinks and crystalline components that slowly reassembled.

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