Phenylethynyl-terminated oligoimides with ultra-low melt viscosity derived from 1,4-bis(3,4-dicarboxy phenoxy)benzene dianhydride

Most of the existing polyimide oligomers for resin transfer molding (RTM) processing exhibited high melt viscosity, which can only maintain below 1 Pa·s at 280°C for 2 h, leading to very high process temperatures. So novel RTM-type oligomers with lower and stable melt viscosities are more desirable. Three series of thermoset oligoimides derived from 1,4-bis(3,4-dicarboxy phenoxy)benzene dianhydride and three different aromatic diamines were prepared herein. The diamines included 4,4′-oxydianiline, 2,2′-bis(trifluoromethyl)benzidine (TFDB), and 2-phenyl-4,4′-diaminodiphenyl ether ( p-ODA). 4-Phenylethynylphthalic anhydride was used as an endcapping reagent. Effects of the chemical structures and molecular weights of the oligoimides on their aggregated structures, melt processability, and the thermal and mechanical properties of the cured films were then systematically investigated. X-Ray diffraction results indicated that ODA series oligoimides and TFDB series oligoimides showed crystallinity in various degrees. However, the asymmetric p-ODA enables the p-ODA series oligoimides to exhibit amorphous forms. It was found that the p-ODA-based oligoimide with a molecular weight of 750 g mol−1 showed very low melt viscosity of 1 Pa·s even at 210°C, and the melt viscosity could maintain below 1 Pa·s after isothermal aging for 2 h at any temperature in the range of 200–280°C by rheological measurements. The cured film also showed a high glass transition temperature of 355°C by dynamic mechanical analysis, very good thermal stability by thermogravimetric analysis, and good mechanical properties. It might be more suitable for RTM processes in the future.

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The Potential for Natural Stones from Northeastern Brazil to Be Used in Civil Construction

Minerals ◽

10.3390/min11050440 ◽

2021 ◽

Vol 11 (5) ◽

pp. 440

Author(s):

Fabiana Pereira da Costa ◽

Jucielle Veras Fernandes ◽

Luiz Ronaldo Lisboa de Melo ◽

Alisson Mendes Rodrigues ◽

Romualdo Rodrigues Menezes ◽

...

Keyword(s):

Mechanical Properties ◽

Thermal Analysis ◽

Differential Thermal Analysis ◽

Chemical Resistance ◽

Mechanical Analysis ◽

Northeastern Brazil ◽

X Ray Diffraction ◽

X Ray ◽

Chemical Agents ◽

Natural Stones

Natural stones (limestones, granites, and marble) from mines located in northeastern Brazil were investigated to discover their potential for use in civil construction. The natural stones were characterized by chemical analysis, X-ray diffraction, differential thermal analysis, and optical microscopy. The physical-mechanical properties (apparent density, porosity, water absorption, compressive and flexural strength, impact, and abrasion) and chemical resistance properties were also evaluated. The results of the physical-mechanical analysis indicated that the natural stones investigated have the potential to be used in different environments (interior, exterior), taking into account factors such as people’s circulation and exposure to chemical agents.

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Synergistic interaction of renewable nipagin and eugenol for high performance aromatic copoly(ether ester) materials

10.21203/rs.3.rs-706272/v1 ◽

2021 ◽

Author(s):

Keling Hu ◽

Huachao Sui ◽

Dongping Zhao

Keyword(s):

High Performance ◽

Synergistic Interaction ◽

Differential Scanning Calorimetric ◽

Gravimetric Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Molecular Weights ◽

Chemical Structures ◽

Naturally Occurring ◽

Ether Ester

Abstract Naturally occurring nipagin and eugenol were used as the collaborative starting materials for poly(ether ester) materials. In this study, two series of nipagin and eugenol-derived copoly(ether ester)s, PHN11-xE1x and PHN11-xE2x (x = 0%, 5%, 10%, 15%, 20%), were prepared with renewable 1,6-hexanediol as a comonomer. The nipagin-derived component acts as the renewable surrogate of petroleum-based dimethyl terephthalate (DMT), while the eugenol-derived component acts as the cooperative property modifier of parent homopoly(ether ester) PHN1. 1,6-Hexanediol was chosen as the spacer because of its renewability and short chain to enhance the glass transition temperatures (Tgs) of materials. The molecular weights and chemical structures were confirmed by gel permeation chromatograph (GPC), NMR and FTIR spectroscopies. Thermal and crystalline properties were studied by thermal gravimetric analysis (TGA), differential scanning calorimetric (DSC) and wide-angle X-ray diffraction (WXRD). The tensile assays were conducted to evaluate the mechanical properties. The results suggest that properties of such kind of poly(ether ester)s can be finely tuned by the relative content of two components. Synergistic interaction of two structurally distinctive parts endows the materials with high performance.

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Salt template zirconia reinforcing particles as possible reinforcement for PMMA matrix composite

Advanced Composites Letters ◽

10.1177/0963693519879696 ◽

2019 ◽

Vol 28 ◽

pp. 096369351987969

Author(s):

AA Elmadani ◽

N Tomić ◽

I Radović ◽

MM Vuksanović ◽

D Stojanović ◽

...

Keyword(s):

Mechanical Properties ◽

Image Analysis ◽

Composite Material ◽

Fourier Transform ◽

Synthesis Method ◽

Mechanical Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Reinforcing Particles ◽

Scanning Electron

To obtain flakes like zirconia particles at relatively low temperature, the synthesis method for producing zirconia particles on the surface of salt particles that serve as a template is examined. The produced particles are incorporated as reinforcement in the poly(methyl methacrylate) matrix to obtain a composite material. The particles were characterized by the X-ray diffraction, Fourier-transform infrared spectroscopy, and image analysis. The morphology of the particles and composites was examined using a field emission scanning electron microscope. Composites prepared with synthesized particles were compared to those containing commercial zirconia particles to estimate the possibility of use of synthesized particles as reinforcement. The influence of the 1 wt% of zirconia particles in composite material on the mechanical properties was studied using microhardness measurements and dynamic mechanical analysis. The results obtained show that the addition of 1 wt% of zirconia particles increases the mechanical properties of the composite relative to the pure polymer matrix.

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Synergistic interaction of renewable nipagin and eugenol for aromatic copoly(ether ester) materials with desired performance

Scientific Reports ◽

10.1038/s41598-021-03614-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Keling Hu ◽

Huachao Sui ◽

Dongping Zhao

Keyword(s):

Differential Scanning Calorimetric ◽

Gravimetric Analysis ◽

X Ray Diffraction ◽

Polybutylene Terephthalate ◽

X Ray ◽

Molecular Weights ◽

Chemical Structures ◽

Naturally Occurring ◽

High Boiling Point ◽

Ether Ester

AbstractNaturally occurring nipagin and eugenol were used as the collaborative starting materials for poly(ether ester) polymers. In this study, two series of nipagin and eugenol-derived copoly(ether ester)s, PHN11−xE1x and PHN11−xE2x (x = 0%, 5%, 10%, 15%, 20%), were prepared with renewable 1,6-hexanediol as a comonomer. The nipagin-derived component acts as the renewable surrogate of petroleum-based dimethyl terephthalate (DMT), while the eugenol-derived component acts as the cooperative property modifier of parent homopoly(ether ester) PHN1. 1,6-Hexanediol was chosen as the spacer because of its renewability, high boiling point, and short chain to enhance the glass transition temperatures (Tgs) of materials. The molecular weights and chemical structures were confirmed by gel permeation chromatograph (GPC), NMR and FTIR spectroscopies. Thermal and crystalline properties were studied by thermal gravimetric analysis (TGA), differential scanning calorimetric (DSC) and wide-angle X-ray diffraction (WXRD). The tensile assays were conducted to evaluate the mechanical properties. The results suggested that properties of this kind of poly(ether ester)s could be finely tuned by the relative content of two components for the desired applications (elastomer, rubbery) suitable for different scenarios from polyethylene glycol terephthalate (PET) and polybutylene terephthalate (PBT).

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Construction of Mechanically Reinforced Thermoplastic Polyurethane from Carbon Dioxide-Based Poly(ether carbonate) Polyols via Coordination Cross-Linking

Polymers ◽

10.3390/polym13162765 ◽

2021 ◽

Vol 13 (16) ◽

pp. 2765

Author(s):

Gaosheng Gu ◽

Jincheng Dong ◽

Zhongyu Duan ◽

Binyuan Liu

Keyword(s):

Carbon Dioxide ◽

Dynamic Mechanical Analysis ◽

Thermoplastic Polyurethane ◽

Mechanical Analysis ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Dynamic Mechanical ◽

Chemical Structures ◽

Vis Spectroscopy

Using carbon dioxide-based poly(propylene ether carbonate) diol (PPCD), isophorone diisocyanate (IPDI), dimethylolbutyric acid (DMBA), ferric chloride (FeCl3), and ethylene glycol (EG) as the main raw materials, a novel thermoplastic polyurethane (TPU) is prepared through coordination of FeCl3 and DMBA to obtain TPU containing coordination enhancement directly. The Fourier transform infrared spectroscopy, 1H NMR, gel permeation chromatography, UV−Vis spectroscopy, tensile testing, dynamic mechanical analysis, X-ray diffraction, differential scanning calorimetry, and thermogravimetric analysis were explored to characterize chemical structures and mechanical properties of as-prepared TPU. With the increasing addition of FeCl3, the tensile strength and modulus of TPU increase. Although the elongation at break decreases, it still maintains a high level. Dynamic mechanical analysis shows that the glass-transition temperature moves to a high temperature gradually along with the increasing addition of FeCl3. X-ray diffraction results indicate that TPUs reinforced with FeCl3 or not are amorphous polymers. That FeCl3 coordinates with DMBA first is an effective strategy of getting TPU, which is effective and convenient in the industry without the separation of intermediate products. This work confirms that such Lewis acids as FeCl3 can improve and adjust the properties of TPU contenting coordination structures with an in-situ reaction in a low addition amount, which expands their applications in industry and engineering areas.

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Synthesis of high Tg and organosoluble poly(N-arylene benzimidazole ether imide) copolymers by C–N/C–O coupling reaction

High Performance Polymers ◽

10.1177/0954008317701822 ◽

2017 ◽

Vol 30 (4) ◽

pp. 465-474 ◽

Cited By ~ 1

Author(s):

Lala Rukh Sidra ◽

Nafeesa Mushtaq ◽

Guofei Chen ◽

Xingzhong Fang

Keyword(s):

Mechanical Properties ◽

Diphenyl Ether ◽

Coupling Reaction ◽

X Ray Diffraction ◽

X Ray ◽

Good Thermal Stability ◽

Copolymer Films ◽

Good Solubility ◽

Nucleophilic Displacement ◽

Amorphous Nature

A series of poly( N-arylene benzimidazole ether imide) copolymers PEIBIs were prepared from 1H,3′H-5,5′-bis-benzimidazole, bisphenol-A and 4,4′-bis(4-fluorophthalimido)diphenyl ether by nucleophilic displacement polymerization. The resulting copolymers PEIBI(10–90) demonstrated moderate to good solubility in polar aprotic solvents and high glass transition temperatures ( Tgs) of 228–336°C, good thermal stability with 10% weight loss temperatures in the range of 503–548°C. All copolymer films showed good mechanical properties with tensile strengths of 101–130 MPa, tensile moduli of 3.3–4.0 GPa, elongations at break of 5–7%, and also presented low water uptake (0.15–0.34%). The wide-angle X-ray diffraction results revealed the amorphous nature of copolymers. The copolymer PEIBI-80 showed good balance in solubility, thermal and mechanical properties.

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Modified MDF Composites Intended for the Refractory Application

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1000.114 ◽

2014 ◽

Vol 1000 ◽

pp. 114-117

Author(s):

Jiří Másilko ◽

Eva Bartoníčková ◽

Radoslav Novotný

Keyword(s):

Flexural Strength ◽

Strontium Aluminate ◽

X Ray Diffraction ◽

X Ray ◽

Good Thermal Stability ◽

Shear Mixing ◽

Mixing Method ◽

Aluminate Cement ◽

Very High

Paper deals with the preparation and characterization of MDF composite based on the strontium-aluminate cement. MDF composites show enhanced mechanical properties, especially flexural strength. Strontium-aluminate cement has got good thermal stability and capabilities at very high temperatures. MDF composites based on strontium-aluminate cement in combination with polyvinylalcohol were prepared by "high shear mixing" method. The prepared samples were subjected to high temperature solid state reaction at various temperatures. Characterization of MDF samples was mainly based on the methods of testing the flexural strength, X-Ray diffraction and thermogravimetry coupled with differential thermal analysis.

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Mechanical properties of FeAlSi powders prepared by mechanical alloying from different initial feedstock materials

Matériaux & Techniques ◽

10.1051/mattech/2018063 ◽

2019 ◽

Vol 107 (2) ◽

pp. 207 ◽

Cited By ~ 2

Author(s):

Jaroslav Čech ◽

Petr Haušild ◽

Miroslav Karlík ◽

Veronika Kadlecová ◽

Jiří Čapek ◽

...

Keyword(s):

Mechanical Properties ◽

Mechanical Alloying ◽

Young’S Modulus ◽

Milling Time ◽

Young's Modulus ◽

Element Model ◽

X Ray Diffraction ◽

X Ray ◽

Powder Particles ◽

Complete Homogenization

FeAl20Si20 (wt.%) powders prepared by mechanical alloying from different initial feedstock materials (Fe, Al, Si, FeAl27) were investigated in this study. Scanning electron microscopy, X-ray diffraction and nanoindentation techniques were used to analyze microstructure, phase composition and mechanical properties (hardness and Young’s modulus). Finite element model was developed to account for the decrease in measured values of mechanical properties of powder particles with increasing penetration depth caused by surrounding soft resin used for embedding powder particles. Progressive homogenization of the powders’ microstructure and an increase of hardness and Young’s modulus with milling time were observed and the time for complete homogenization was estimated.

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Defect-Mediated Conductivity Enhancements in Na3-xPn1-xWxS4 (Pn = P, Sb) using Aliovalent Substitutions

10.26434/chemrxiv.9943961.v2 ◽

2019 ◽

Author(s):

Till Fuchs ◽

Sean Culver ◽

Paul Till ◽

Wolfgang Zeier

Keyword(s):

Ionic Conductivity ◽

Vacancy Concentration ◽

Sodium Ion ◽

High Ionic Conductivity ◽

Ionic Conductors ◽

X Ray Diffraction ◽

X Ray ◽

Solid State Batteries ◽

Ion Conducting ◽

Very High

The sodium-ion conducting family of Na3PnS4, with Pn = P, Sb, have gained interest for the use in solid-state batteries due to their high ionic conductivity. However, significant improvements to the conductivity have been hampered by the lack of aliovalent dopants that can introduce vacancies into the structure. Inspired by the need for vacancy introduction into Na3PnS4, the solid solutions with WS42- introduction are explored. The influence of the substitution with WS42- for PS43- and SbS43-, respectively, is monitored using a combination of X-ray diffraction, Raman and impedance spectroscopy. With increasing vacancy concentration improvements resulting in a very high ionic conductivity of 13 ± 3 mS·cm-1 for Na2.9P0.9W0.1S4 and 41 ± 8 mS·cm-1 for Na2.9Sb0.9W0.1S4 can be observed. This work acts as a stepping-stone towards further engineering of ionic conductors using vacancy-injection via aliovalent substituents.

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