Star-shaped arylacetylene resins derived from silicon

2020 ◽  
Vol 40 (8) ◽  
pp. 676-684
Author(s):  
Niping Dai ◽  
Junkun Tang ◽  
Manping Ma ◽  
Xiaotian Liu ◽  
Chuan Li ◽  
...  
Keyword(s):  
High Performance ◽  
Room Temperature ◽  
Mechanical Test ◽  
Flexural Modulus ◽  
Mechanical Analysis ◽  
Reinforced Composites ◽  
Scanning Calorimetry ◽  
Chemical Structures ◽  
Structures And Properties ◽  
High Performance Resin

AbstractStar-shaped arylacetylene resins, tris(3-ethynyl-phenylethynyl)methylsilane, tris(3-ethynyl-phenylethynyl) phenylsilane, and tris (3-ethynyl-phenylethynyl) silane (TEPHS), were synthesized through Grignard reaction between 1,3-diethynylbenzene and three types of trichlorinated silanes. The chemical structures and properties of the resins were characterized by means of nuclear magnetic resonance, fourier-transform infrared spectroscopy, Haake torque rheomoter, differential scanning calorimetry, dynamic mechanical analysis, mechanical test, and thermogravimetric analysis. The results show that the melt viscosity at 120 °C is lower than 150 mPa⋅s, and the processing windows are as wide as 60 °C for the resins. The resins cure at the temperature as low as 150 °C. The good processabilities make the resins to be suitable for resin transfer molding. The cured resins exhibit high flexural modulus and excellent heat-resistance. The flexural modulus of the cured TEPHS at room temperature arrives at as high as 10.9 GPa. Its temperature of 5% weight loss (Td5) is up to 697 °C in nitrogen. The resins show the potential for application in fiber-reinforced composites as high-performance resin in the field of aviation and aerospace.

Bio-Crude by Acidic Phenolation and Carbamation for the Preparation of Phenolic Thermosetting Resin and Its Application in Thermoresistant Laminates

2019 ◽  
Vol 17 (4) ◽  
Author(s):  
Huan Wang ◽  
Zhuo Wang ◽  
Penggang Ren ◽  
Mingcun Wang
Keyword(s):  
High Performance ◽  
Phenolic Resin ◽  
Mechanical Test ◽  
Chemical Reactivity ◽  
Cost Effective ◽  
Mechanical Analysis ◽  
Thermosetting Resin ◽  
Scanning Calorimetry ◽  
Three Point Bending ◽  
Mechanical Performances

Abstract Fir sawdust was liquefied in phenol solvent under acidic catalyst at 135, 150 and 165 °C, respectively; after neutralization, bio-crude was obtained where contained oil-like liquid and tiny powder-like residue. The bio-crude was chemically modified with urea at high temperature (e. g. > 130 °C) to form carbamate so as to improve chemical reactivity of bio-crude in phenolic resin synthesis. The carbamate-containing bio-crude was condensed with paraformaldehyde into thermosetting phenolic resin. Finally, this biomass-derived phenolic resin matrixed silica fabric laminates were processed. The uncured and thermally cured bio-based resins were characterized by the techniques of Differential Scanning Calorimetry (DSC), Fourier Transform Infrared spectrum (FT-IR), rheology and Thermogravimetric Analysis (TGA), and the laminates’ structure and mechanical performances were studied using the methods of Scanning Electron Microscopy (SEM), three point bending mechanical test and Dynamic Mechanical Analysis (DMA). The results showed: (1) the chemical reactivity of bio-crude was highly improved by carbamation; (2) biomass-derived thermosetting phenolic resin was thermally curable at 150–250 °C (with two exothermic peaks at 185 °C and 220 °C); (3) the char yield was about 47 %, which was not in apparent relationship with sawdust liquefaction temperatures; (4) flexural strength of silica fabric laminates at room temperature was around 357 MPa (similar with that of conventional phenolic laminate); (5) glass transition temperature of silica fabric laminate was above 270 °C (much higher than Tg of conventional phenolic resin laminate, which is normally at 215 °C). The biomass-derived phenolic resin is expected to be widely used as cost-effective and environment-friendly thermosetting resin in the application of high-performance composites.

scholarly journals Preparation, Thermal, and Thermo-Mechanical Characterization of Polymeric Blends Based on Di(meth)acrylate Monomers

Polymers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 878
Author(s):  
Krystyna Wnuczek ◽  
Andrzej Puszka ◽  
Łukasz Klapiszewski ◽  
Beata Podkościelna
Keyword(s):  
Mechanical Analysis ◽  
Attenuated Total Reflection ◽  
Scanning Calorimetry ◽  
Force Microscopy ◽  
Chemical Structures ◽  
Atomic Force ◽  
Polymeric Blends ◽  
Ft Ir ◽  
Acrylate Monomers ◽  
Synthesized Materials

This study presents the preparation and the thermo-mechanical characteristics of polymeric blends based on di(meth)acrylates monomers. Bisphenol A glycerolate diacrylate (BPA.GDA) or ethylene glycol dimethacrylate (EGDMA) were used as crosslinking monomers. Methyl methacrylate (MMA) was used as an active solvent in both copolymerization approaches. Commercial polycarbonate (PC) was used as a modifying soluble additive. The preparation of blends and method of polymerization by using UV initiator (Irqacure® 651) was proposed. Two parallel sets of MMA-based materials were obtained. The first included more harmless linear hydrocarbons (EGDMA + MMA), whereas the second included the usually used aromatic copolymers (BPA.GDA + MMA). The influence of different amounts of PC on the physicochemical properties was discussed in detail. Chemical structures of the copolymers were confirmed by attenuated total reflection–Fourier transform infrared (ATR/FT-IR) spectroscopy. Thermo-mechanical properties of the synthesized materials were investigated by means of differential scanning calorimetry (DSC), thermogravimetric (TG/DTG) analyses, and dynamic mechanical analysis (DMA). The hardness of the obtained materials was also tested. In order to evaluate the surface of the materials, their images were obtained with the use of atomic force microscopy (AFM).

Thermal properties of polybenzoxazine exhibiting improved toughness: Blending with cyclodextrin and its derivatives

2021 ◽  
pp. 095400832110130
Author(s):  
Hailong Li ◽  
Sipei Zhao ◽  
Li Pei ◽  
Zihe Qiao ◽  
Ding Han ◽  
...  
Keyword(s):  
Thermal Properties ◽  
Hydrogen Bonds ◽  
High Performance ◽  
Practical Application ◽  
Scanning Calorimetry ◽  
Thermoset Resins ◽  
Chemical Structures ◽  
Microscopy Techniques ◽  
Fractured Surface ◽  
Scanning Electron

Polybenzoxazines are emerging as a class of high-performance thermoset polymers that can find their applications in various fields. However, its practical application is limited by its low toughness. The cyclic β-cyclodextrin and a newly synthesized derivative (β-cyclodextrin-MAH) were separately blended with benzoxazine to improve the toughness of polybenzoxazine. The results revealed that the maximum impact strength of the blend was 12.24 kJ·m−2 and 14.29 kJ·m−2 when 1 wt.% of β-Cyclodextrin and β-Cyclodextrin-MAH, respectively, were used. The strengths were 53% and 86% higher than that of pure polybenzoxazine. The curing reaction, possible chemical structures, and fractured surface were examined using differential scanning calorimetry, Fourier transform infrared spectroscopy, and scanning electron microscopy techniques to understand the mechanism of generation of toughness. The results revealed that the sea-island structure and the presence of hydrogen bonds between polybenzoxazine and β-cyclodextrin and β-cyclodextrin-MAH resulted in the generation of toughness. Furthermore, the curves generated during thermogravimetric analysis did not significantly change, revealing the good thermal properties of the system. The phase-separated structure and the hydrogen bonds present in the system can be exploited to prepare synergistically tough polybenzoxazine exhibiting excellent thermal properties. This can be a potential way of modifying the thermoset resins.

Thermal and Mechanical Properties of Highly-Filled Polybenzoxazine-Alumina Composites

2013 ◽  
Vol 545 ◽  
pp. 211-215 ◽  
Author(s):  
Jirawat Kajornchaiyakul ◽  
Chanchira Jubsilp ◽  
Sarawut Rimdusit
Keyword(s):  
Room Temperature ◽  
Alumina Particle ◽  
Mechanical Analysis ◽  
Interfacial Interaction ◽  
Alumina Content ◽  
Mechanical And Thermal Properties ◽  
Thermal And Mechanical Properties ◽  
Scanning Calorimetry ◽  
Glass Transition Temperatures ◽  
Alumina Composites

-Highly filled alumina polymer composites based on bisphenol-A/aniline benzoxazine resin (BA-a) were developed. The mechanical and thermal properties of these highly filled composites at various alumina filler contents from 0 to 85 % by weight were studied by dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC). The experimental results revealed that the storage modulus (E') at room temperature was increased from 5.93 GPa of the neat polybenzoxazine up to about 45.27 GPa of the composites with the maximum alumina content of 83 % by weight. The glass-transition temperatures (Tg) of the composites systematically increased with increasing the alumina filler contents. The Tgs of the obtained composites having alumina content ranging from 50 to 83 % by weight were found to be 178°C to 188°C, which higher that the Tg of the polybenzoxazine, i.e. 176°C implying substantial interfacial interaction between the alumina particle and the polybenzoxazine.

scholarly journals The Influence of Sub-Zero Conditions on the Mechanical Properties of Polylactide-Based Composites

Materials ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 5789
Author(s):  
Olga Mysiukiewicz ◽  
Mateusz Barczewski ◽  
Arkadiusz Kloziński
Keyword(s):  
Mechanical Properties ◽  
Room Temperature ◽  
Mechanical Performance ◽  
Mechanical Analysis ◽  
Uniaxial Tensile ◽  
Uniaxial Tensile Test ◽  
Mechanical And Thermal Properties ◽  
Scanning Calorimetry ◽  
Linseed Cake ◽  
Static Mechanical

Polylactide-based composites filled with waste fillers due to their sustainability are a subject of many current papers, in which their structural, mechanical, and thermal properties are evaluated. However, few studies focus on their behavior in low temperatures. In this paper, dynamic and quasi-static mechanical properties of polylactide-based composites filled with 10 wt% of linseed cake (a by-product of mechanical oil extraction from linseed) were evaluated at room temperature and at −40 °C by means of dynamic mechanical analysis (DMA), Charpy’s impact strength test and uniaxial tensile test. It was found that the effect of plasticization provided by the oil contained in the filler at room temperature is significantly reduced in sub-zero conditions due to solidification of the oil around −18 °C, as it was shown by differential scanning calorimetry (DSC) and DMA, but the overall mechanical performance of the polylactide-based composites was sufficient to enable their use in low-temperature applications.

scholarly journals Effect of MWCNT on Thermal, Mechanical, and Morphological Properties of Polybutylene Terephthalate/Polycarbonate Blends

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
C. P. Rejisha ◽  
S. Soundararajan ◽  
N. Sivapatham ◽  
K. Palanivelu
Keyword(s):  
Mechanical Properties ◽  
High Performance ◽  
Flexural Modulus ◽  
Tensile Modulus ◽  
Nucleating Agent ◽  
Mechanical Analysis ◽  
Morphological Properties ◽  
Multiwall Carbon Nanotube ◽  
Polybutylene Terephthalate ◽  
The Impact

This paper evaluated the effect of multiwall carbon nanotube (MWCNT) on the properties of PBT/PC blends. The nanocomposites were obtained by melt blending MWCNT in the weight percentages 0.15, 0.3, and 0.45 wt% with PBT/PC blends in a high performance corotating twin screw extruder. Samples were characterized by tensile testing, dynamic mechanical analysis, thermal analysis, scanning electron microscopy, and X-ray diffraction. Concentrations of PBT and PC are optimized as 80 : 20 based on mechanical properties. A small amount of MWCNT shows better increase in the thermal and mechanical properties of the blends of PBT/PC nanocomposite when compared to nanoclays or inorganic fillers. The ultimate tensile strength of the nanocomposites increased from 54 MPa to 85 MPa with addition of MWCNT up to 0.3% and then decreased.The tensile modulus values were increased to about 60% and the flexural modulus was more than about 80%. The impact strength was also improved with 20% PC to about 60% and with 0.15% MWCNT to about 50%. The HDT also improved from 127°C to 205°C. It can be seen from XRD result that the crystallinity of PBT is less affected by incorporating MWCNT. The crystallizing temperature was increased and the MWCNT may act as a strong nucleating agent.

HIGH-IMPACT PP NANOCOMPOSITES: INFLUENCE OF CLAY CONTENT ON MECHANICAL AND THERMAL PROPERTIES

2013 ◽  
Vol 12 (06) ◽  
pp. 1350039
Author(s):  
L. G. FURLAN ◽  
RICARDO V. B. OLIVEIRA ◽  
ANDRÉIA C. E. MELLO ◽  
SUSANA A. LIBERMAN ◽  
MAURO A. S. OVIEDO ◽  
...  
Keyword(s):  
Thermal Properties ◽  
Impact Strength ◽  
Flexural Modulus ◽  
Clay Content ◽  
Mechanical Analysis ◽  
High Impact ◽  
Mechanical And Thermal Properties ◽  
Scanning Calorimetry ◽  
Transmission Electron ◽  
Izod Impact

The preparation of high-impact polypropylene nanocomposites with different organo-montmorillonite (O-MMT) contents by means of meltprocessing was investigated. The nanocomposite properties were evaluated by transmission electron microscopy (TEM), flexural modulus, izod impact strength, dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). It was noticed that the PP/O-MMT nanocomposites properties were affected by clay content. Exceptional improvements in impact strength were obtained (maximum of 185%) by the use of low O-MMT content. The results showed that higher enhancement on mechanical/thermal properties was obtained by 3 wt.% of O-MMT instead of higher quantities.

scholarly journals The Effects of Reprocessing and Fiber Treatments on the Properties of Polypropylene-Sugarcane Bagasse Biocomposites

Polymers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1440 ◽  
Author(s):  
Juan P. Correa-Aguirre ◽  
Fernando Luna-Vera ◽  
Carolina Caicedo ◽  
Bairo Vera-Mondragón ◽  
Miguel A. Hidalgo-Salazar
Keyword(s):  
Mechanical Properties ◽  
Sugarcane Bagasse ◽  
Flexural Modulus ◽  
Melting Process ◽  
Extrusion Process ◽  
Mechanical Analysis ◽  
Strength Increase ◽  
Scanning Calorimetry ◽  
Chemical Treatments ◽  
Recycling Potential

This study explores the reprocessing behavior of polypropylene-sugarcane bagasse biocomposites using neat and chemically treated bagasse fibers (20 wt.%). Biocomposites were reprocessed 5 times using the extrusion process followed by injection molding. The mechanical properties indicate that microfibers bagasse fibers addition and chemical treatments generate improvements in the mechanical properties, reaching the highest performance in the third cycle where the flexural modulus and flexural strength increase 57 and 12% in comparison with neat PP. differential scanning calorimetry (DSC) and TGA characterization show that bagasse fibers addition increases the crystallization temperature and thermal stability of the biocomposites 7 and 39 °C respectively, without disturbing the melting process of the PP phase for all extrusion cycles. The rheological test shows that viscosity values of PP and biocomposites decrease progressively with extrusion cycles; however, Cole–Cole plots, dynamic mechanical analysis (DMA), width at half maximum of tan delta peaks and SEM micrographs show that chemical treatments and reprocessing could improve fiber dispersion and fiber–matrix interaction. Based on these results, it can be concluded that recycling potential of polypropylene-sugarcane bagasse biocomposites is huge due to their mechanical, thermal and rheological performance resulting in advantages in terms of sustainability and life cycle impact of these materials.

Novel amino-containing fluorene-based bisphthalonitrile compounds with flexible group

2017 ◽  
Vol 30 (7) ◽  
pp. 767-775 ◽  
Author(s):  
An-ran Wang ◽  
Abdul Qadeer Dayo ◽  
Dan Lv ◽  
Yi-le Xu ◽  
Jun Wang ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Mechanical Analysis ◽  
Proton Nuclear Magnetic Resonance ◽  
Scanning Calorimetry ◽  
Rheological Analysis ◽  
Chemical Structures ◽  
The Fourier Transform ◽  
Alkoxy Groups ◽  
Nuclear Magnetic

A series of amino-containing fluorene-based bisphthalonitrile (AFPN) monomers with alkyl or alkoxy groups were successfully produced by the reaction of 4-nitrophthalonitrile with 9, 9-bis (3-alkyl (or alkoxy)-4-aminophenyl)-2, 7-dihydroxylfluorene in the presence of potassium carbonate by a nucleophilic substitution reaction. The chemical structures of the synthesized monomers were confirmed by the Fourier transform infrared (FTIR), proton nuclear magnetic resonance, and carbon-13 nuclear magnetic resonance analyses. The synthesized monomers’ curing behaviors were evaluated by FTIR and differential scanning calorimetry, and a rheological analysis was performed to evaluate their respective processabilities. Moreover, dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA) were performed for the thermomechanical, thermal, and thermo-oxidative analyses of the polymers. The results confirmed that the newly prepared phthalonitrile (PN) monomers with alkyl or alkoxy groups exhibited a self-promoted curing behavior. The rheological analysis suggested that the processing windows of the synthesized monomers were wider than that of APFN monomer bearing no flexible group. DMA and TGA revealed that the cured polymers exhibited high glass transition temperature (358–416°C) and the char yields at 800°C under nitrogen were between 70% and 77%. Moreover, the introduction of alkyl or alkoxy groups into the PN monomers’ backbones slightly reduced the thermal stability of the resulting polymers.

scholarly journals Fabrication of Ultrafine PPS Fibers with High Strength and Tenacity via Melt Electrospinning

Polymers ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 530 ◽  
Author(s):  
Zuo-Ze Fan ◽  
Hong-Wei He ◽  
Xu Yan ◽  
Ren-Hai Zhao ◽  
Yun-Ze Long ◽  
...  
Keyword(s):  
High Performance ◽  
Room Temperature ◽  
High Strength ◽  
Polyphenylene Sulfide ◽  
Crystallization Peak ◽  
Elongation At Break ◽  
Ultrafine Fibers ◽  
Melt Electrospinning ◽  
High Performance Resin ◽  
Uniform Diameter

Electrospinning (e-spinning) is an emerging technique to prepare ultrafine fibers. Polyphenylene sulfide (PPS) is a high-performance resin which does not dissolve in any solvent at room temperature. Commercial PPS fibers are produced mainly by meltblown or spunbonded process to give fibers ~20 μm in diameter. In this research, an in-house designed melt electrospinning device was used to fabricate ultrafine PPS fibers, and the e-spinning operation conducted under inert gas to keep PPS fibers from oxidizing. Under the optimum e-spinning conditions (3 mm of nozzle diameter, 30 kV of electrostatic voltage, and 9.5 cm of tip-to-collector distance), the as-spun fibers were less than 8.0 μm in diameter. After characterization, the resultant PPS fibers showed uniform diameter and structural stability. Compared with commercial PPS staple fibers, the obtained fibers had a cold crystallization peak and 10 times higher storage modulus, thereby offering better tensile tenacity and more than 400% elongation at break.

Sign in / Sign up

Export Citation Format

Share Document