scholarly journals Storage Moduli of in situ Polymerised and Melt Extruded PA6 Graphite (G) Composites

2021 ◽  
Vol 5 (1) ◽  
pp. 91-101
Author(s):  
M. Umar ◽  
M. I. Ofem ◽  
A. S. Anwar ◽  
M. M. Usman
Keyword(s):  
Storage Modulus ◽  
Processing Condition ◽  
Rotation Frequency ◽  
Reaction Rates ◽  
Carbon Composite ◽  
Melt Processing ◽  
Effective Modulus ◽  
Melt Extrusion ◽  
System A

Four PA6/graphite (G) composites systems were made. Two in situ polymerisation equivalent in mixing strain and two melt extrusion of equivalent processing strain. The effective modulus of the carbons, room temperature storage modulus and storage modulus at 80 ⁰C were evaluated using Dynamic Mechanical and thermal Analysis (DMTA). Melt processing, was employed to make PA6/carbon composite systems over a range of loadings of Graphite (G) and Graphite Nano Platelets (GNP) fillers. Melt extrusion was carried out using 100/6 processing condition, which indicates an extrusion screw rotation frequency of 100 rpm applied for 6 minutes (min) and 200/3 processing conditions, of 200 rpm for 3 min. For in situ polymerised systems G and GNP dispersion was made using two similar conditions designated as 40/10 and 20/20. Here, 40/10 indicates that sonication amplitude of 40% was applied for 10 min, whereas in the 20/20 conditions, amplitude of 20% was applied for 20 min. For in situ Nano P INP 40/10 systems weak interaction between PA6 and GNP is indicated by the very low modulus enhancement above glass transition temperature (Tg). The modulus behaviour shows that the reinforcement provided by GNP is not significant relative to unfilled PA6, despite the low loading levels. A similar, but less pronounced, behaviour is observed for INP 20/20 system. Effective modulus for the in situ polymerised systems INP 40/10, was 4.8 GPa. Due to the low loading level of GNP used and the better reaction rates, an extrapolated modulus of 22.4 GPa is obtained in the INP 20/20 system. For G200/3 and G100/6 the trend of increasing modulus with GNP loading is not followed exactly. On all levels of loading, the relative modulus values of the INP 20/20 system are higher than those of the 40/10 system, a reflection of retention or improvement in the aspect ratio of the GNP due to less intensive sonication.

Perovskite framework NH4FeF3/carbon composite nanosheets as a potential anode material for Li and Na ion storage

2017 ◽  
Vol 5 (36) ◽  
pp. 19280-19288 ◽  
Author(s):  
Minhong Kong ◽  
Kunhong Liu ◽  
Jinyu Ning ◽  
Jisheng Zhou ◽  
Huaihe Song
Keyword(s):  
Anode Material ◽  
Carbon Composite ◽  
Pyrolysis Method ◽  
Ion Storage

Perovskite framework NH4FeF3/CNS composites were prepared by an in situ co-pyrolysis method and exhibit better performance as anodes for both LIBs and SIBs.

Semi-Electrical Conductivity of Gelcast Alumina Sintered under Nitrogen Atmosphere

2006 ◽  
Vol 11-12 ◽  
pp. 493-496 ◽  
Author(s):  
Ruben L. Menchavez ◽  
Koichiro Adachi ◽  
Masayoshi Fuji ◽  
Minoru Takahashi
Keyword(s):  
Electrical Conductivity ◽  
Electrical Resistance ◽  
Sintered Sample ◽  
Carbon Composite ◽  
Nitrogen Atmosphere ◽  
Potential Candidate ◽  
Nitrogen Gas ◽  
Conductive Property ◽  
Carbon Network

This work demonstrated an in-situ pyrolysis of gelcast alumina under reduction sintering to make alumina and carbon composite in providing semi-electrical conductivity. To increase the carbon content, the monomer was varied in the premix solution with reduction sintering in nitrogen gas. Two-probe method was used to measure electrical resistance of the sintered samples. The results revealed that the increase of monomer addition and sintering treatment were effective in reducing electrical resistance. The lowest value was 3.6×106-cm, which is a potential candidate for electrostatic shielding application. The reduction-sintered sample was re-sintered in an air in order to gain insight on the conductive path due to carbon network. Further tests such as XRD, TGA/DTA, and scanning electron microscopywere used to explain the semi-conductive property of the material.

Biodegradable Polyester / Layered Silicate Nanocomposites

2002 ◽  
Vol 740 ◽  
Author(s):  
Pralay Maiti ◽  
Carl A. Batt ◽  
Emmanuel P. Giannelis
Keyword(s):  
Mechanical Properties ◽  
Storage Modulus ◽  
Layered Silicate ◽  
Layered Silicates ◽  
Melt Extrusion ◽  
Biodegradable Polyester ◽  
Modified Montmorillonite ◽  
Organically Modified Montmorillonite ◽  
Silicate Nanocomposites ◽  
Organically Modified

ABSTRACTNanocomposites of α-hydroxy polyester, polylactide (PLA) and β-hydroxy polyester, polyhydroxybutyrate (PHB) with layered silicates have been successfully prepared by melt extrusion of PLA and PHB with organically modified montmorillonite (MMT) and fluoromica. The mechanical properties of the nanocomposites are improved compared to the neat polymers. Storage modulus increase up to 40% compared with the pure polymers by adding only 2–3 wt% nanoclay. Biodegradation can be controlled by the choice of the nanoclay used.

scholarly journals Monitoring the Interfacial Polymerization of Piperazine and Trimesoyl Chloride with Hydrophilic Interlayer or Macromolecular Additive by in-situ FT-IR Spectroscopy

2019 ◽  
Author(s):  
Xi Yang
Keyword(s):  
Ir Spectroscopy ◽  
Reaction Rate ◽  
Interfacial Polymerization ◽  
Reaction System ◽  
Reaction Rates ◽  
Water Permeation ◽  
Ft Ir ◽  
Trimesoyl Chloride ◽  
Ft Ir Spectroscopy

The interfacial polymerization (IP) of piperazine (PIP) and trimesoyl chloride (TMC) has been extensively utilized to synthesize the nanofiltration (NF) membrane. However, it is still a huge challenge to monitor the IP reaction, because of the fast reaction rate and the formed ultra-thin film. Herein, two effective strategies are applied to reduce the IP reaction rate: (1) the introduction of hydrophilic interlayers between the porous substrate and the formed polyamide layer; (2) the addition of macromolecular additives in the aqueous solution of PIP. As a result, in-situ FT-IR spectroscopy was firstly used to monitor the IP reaction of PIP/TMC reaction system, with hydrophilic interlayers or macromolecular additives. Moreover, we study the formed polyamide layer growth on the substrate, in a real-time manner. The in-situ FT-IR experimental results confirm that the IP reaction rates are effectively suppressed and the formed polyamide thickness reduces from 138±24 nm to 46±2 nm. Furthermore, the optimized NF membrane with excellent performance are consequently obtained, which include the boosted water permeation flux about 141~238 (L·m2·h/MPa) and superior salt rejection of Na2SO4 > 98.4%.

scholarly journals Photocatalytic Degradation of Methylene Blue under UV Light Irradiation on Prepared CarbonaceousTiO2

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Zatil Amali Che Ramli ◽  
Nilofar Asim ◽  
Wan N. R. W. Isahak ◽  
Zeynab Emdadi ◽  
Norasikin Ahmad-Ludin ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Activated Carbon ◽  
In Situ Polymerization ◽  
Uv Light ◽  
Carbon Composite ◽  
Light Irradiation ◽  
Uv Light Irradiation ◽  
Transmission Electron ◽  
Vis Spectroscopy

This study involves the investigation of altering the photocatalytic activity of TiO2using composite materials. Three different forms of modified TiO2, namely, TiO2/activated carbon (AC), TiO2/carbon (C), and TiO2/PANi, were compared. The TiO2/carbon composite was obtained by pyrolysis of TiO2/PANi prepared by in situ polymerization method, while the TiO2/activated carbon (TiO2/AC) was obtained after treating TiO2/carbon with 1.0 M KOH solution, followed by calcination at a temperature of 450°C. X-ray powder diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR), thermogravimetric analysis (TG-DTA), Brunauer-Emmet-Teller (BET), and UV-Vis spectroscopy were used to characterize and evaluate the prepared samples. The specific surface area was determined to be in the following order: TiO2/AC > TiO2/C > TiO2/PANi > TiO2(179 > 134 > 54 > 9 m2 g−1). The evaluation of photocatalytic performance for the degradation of methylene blue under UV light irradiation was also of the same order, with 98 > 84.7 > 69% conversion rate, which is likely to be attributed to the porosity and synergistic effect in the prepared samples.

Sulfur nanoparticles/disordered mesoporous carbon composite based on nanotemplates in-situ transformation route

2018 ◽  
Vol 706 ◽  
pp. 133-139 ◽  
Author(s):  
Haijuan Pei ◽  
Rui Guo ◽  
Wentao Guo ◽  
Wen Liu ◽  
Yong Li ◽  
...  
Keyword(s):  
Mesoporous Carbon ◽  
Carbon Composite ◽  
Sulfur Nanoparticles

Triphosgene/Sodium Organosulfinate System: A General and Efficient Electrophilic Thiolation of Silylenol Ethers and Electron-Rich Heteroaromatics

Synlett ◽  
2020 ◽  
Vol 31 (18) ◽  
pp. 1838-1842
Author(s):  
Yan-qin Yuan ◽  
Sheng-rong Guo ◽  
Hai-jun Gao ◽  
Yu-xin Gu ◽  
Zhe-fei Wang ◽  
...  
Keyword(s):  
Practical Approach ◽  
Heteroaromatic Compounds ◽  
System A ◽  
Powerful Approach

AbstractAn efficient and practical approach to electrophilic thiolation was developed by using commercially available triphosgene as a reductant and the appropriate alkyl- or arylsulfinates, which were transformed in situ into electrophilic RSCl intermediates in the presence of triphosgene. This procedure represents a general and powerful approach for the synthesis of α-(trifluoromethyl)thio-substituted ketones and thiolated electron-rich heteroaromatic compounds.

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