Influence of Non-Functionalized and Functionalized MWCNTs on Mechanical and Thermal Properties of Epoxy Composites

2010 ◽  
Author(s):  
Shaik Zainuddin ◽  
Mahesh Hosur ◽  
Harish Rao ◽  
Rajib Barua ◽  
Shaik Jeelani ◽  
...  
Keyword(s):  
Epoxy Resin ◽  
Thermo Gravimetric Analysis ◽  
Mechanical Analysis ◽  
Flexural Properties ◽  
Mechanical And Thermal Properties ◽  
Gravimetric Analysis ◽  
Thermo Gravimetric ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes ◽  
Functionalized Mwcnts

In this work, SC-15 epoxy resin was modified using 0.1–0.3 wt. % of non-functionalized and functionalized multi-walled carbon nanotubes (MWCNTs) using conventional and solvent based methods. A high-intensity ultrasonic liquid processor was used to disperse MWCNTs in solvent and to obtain a homogeneous molecular mixture of epoxy resin and MWCNTs. Viscosity, dynamic mechanical analysis (DMA), thermo-gravimetric analysis (TGA), tensile and flexure tests were performed on unfilled and 0.1–0.3 wt. % MWCNTs filled SC-15 epoxy. Preliminary results indicate increase in viscosity with increase in MWCNTs wt. % loading and 0.2 wt. % MWCNTs epoxy samples showed the highest improvement in tensile and flexural properties as compared to the neat system. DMA studies also revealed that 0.2 wt. % doped system exhibit the highest storage modulus and Tg as compared to neat and other loading percentages. TGA results show that amino functionalized MWCNTs samples are more thermally stable.

Thermo-mechanical properties of epoxy nanocomposites incorporating amino acid and acid functionalized multi-walled carbon nanotubes

2019 ◽  
Vol 54 (14) ◽  
pp. 1847-1861
Author(s):  
Alireza Bagherzade ◽  
Masoud Jamshidi
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Amino Acid ◽  
Epoxy Resin ◽  
Acid Treatment ◽  
Curing Temperature ◽  
Gravimetric Analysis ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes ◽  
Functionalized Mwcnts

In this study, multi-walled carbon nanotubes (MWCNTs) were functionalized by both sulfuric/nitric acids and amino acids to form COOH and NH2/COOH/OH groups on their surface, respectively. The functionalized MWCNTs were characterized by Fourier Transform Infrared Spectroscopy, titration test, thermal gravimetric analysis, and solvent stability test. The results revealed that in each method, the functional groups were successfully attached to the surface of nanotubes. Acid treatment grafted more oxygen-containing groups compared to commercial carboxylated MWCNTs. The amino acid functionalized MWCNTs indicated improved stability in different solvents compared to raw and acid treated MWCNTs. These functionalized MWCNTs were incorporated into epoxy resin and the properties of the nanocomposites were evaluated by scanning electron microscopy, tensile test, dynamic mechanical thermal analysis, differential scanning calorimetry, and thermogravimetric analysis. The morphology of the nanocomposites revealed that acid and amino acid treated samples had better interaction with the epoxy resin. Compared to epoxy sample contained raw MWCNT (control) and commercial carboxylated MWCNTs, the addition of functionalized MWCNTs to the epoxy resin improved the tensile strength by 39% and 25% (for acid treated) and 46% and 33% (for amino acid treated), respectively. The best tensile properties for acid and amino acid treated samples were reached by MWCNTs acid treated at 110℃ for 15 min and MWCNTs treated in a 50 g/L aqueous solution of amino acid, respectively. Storage modulus of the epoxy samples which contained acid and amino acid treated MWCNTs were 1560 and 1900 MPa, respectively. The glass rubber transition temperature ( Tg) of the epoxy samples containing acid and amino acid treated nanotubes were increased by 1.1℃ and 5.9℃, respectively, compared to the control sample. Therefore, based on these mechanical properties, the epoxy samples containing nanotubes functionalized by amino acid exhibited the highest performance in the epoxy nanocomposite. Incorporating acid and amino acid treated MWCNTs accelerated the curing process of epoxy where the curing temperature decreased by 9.1℃ and 13.3℃, respectively. Because of the reaction between amine groups grafted on MWCNTs in the amino acid treatment and epoxide groups of the epoxy resin, this acceleration was more significant in the case of amino acid sample. Note that addition of functionalized MWCNTs to epoxy resin did not lead to increased thermal stability.

scholarly journals Influence of different functionalization methods of multi-walled carbon nanotubes on the properties of poly(L-lactide) based nanocomposites

2019 ◽  
Vol 73 (3) ◽  
pp. 183-196 ◽  
Author(s):  
Nevena Vukic ◽  
Ivan Ristic ◽  
Milena Marinovic-Cincovic ◽  
Radmila Radicevic ◽  
Branka Pilic ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Thermo Gravimetric Analysis ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Transmission Electron ◽  
Multi Walled Carbon Nanotubes ◽  
Ft Ir ◽  
Walled Carbon Nanotubes ◽  
Functionalized Mwcnts

This paper presents influence of the type of carbon nanotube functionalization on properties of poly(L-lactide) (PLLA) based nanocomposite materials. For this purpose surface modifications of multi-walled carbon nanotubes (MWCNTs) were performed by chemical and irradiation techniques, while thermo gravimetric analysis, UV-Visible and Fourier-transform infrared (FT-IR) spectroscopies confirmed successful covalent functionalization. Series of PLLA bionanocom-posites with different contents of functionalized MWCNTs (0.7; 1.6; 2.1 wt%), were synthesized via ring-opening solution polymerisation of L-lactide. FT-IR analysis confirmed that grafting of L-lactide, under controlled condition, is possible to perform starting from the surface of functionalized MWCNTs. From differential scanning calorimetry results it was concluded that even low contents of chemically and irradiation functionalized MWCNTs had a significant effect on thermal properties of the prepared nanocomposites, raising the values of melting and glass transition temperatures. Thermogravimetric analysis (TGA) has shown that the degradation onset temperature for composites with chemically functionalized MWCNTs, was much higher than that for the neat poly(L-lactide) sample and composites with irradiation functionalized MWCNTs. Morphology studies by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) indicated that poly(L-lactide) covered surfaces and separated functionalized MWCNTs. Good dispersion of carbon nanotubes in polymer matrix enabled conductivity of synthesized materials, as determined by conductivity tests.

Curing Process and Heat-Resistance of Polyethersulfone Toughened Epoxy Resins

2017 ◽  
Vol 898 ◽  
pp. 2302-2308
Author(s):  
Jin Li Zhou ◽  
Shu Zhu ◽  
Wen Pin Jia ◽  
Chao Cheng ◽  
Elwathig A.M. Hassan ◽  
...  
Keyword(s):  
Heat Resistance ◽  
Epoxy Resin ◽  
Thermo Gravimetric Analysis ◽  
Exothermic Peak ◽  
Curing Temperature ◽  
Gravimetric Analysis ◽  
Curing Process ◽  
Thermo Gravimetric ◽  
Rich Phase ◽  
Curing Reaction

In order to improve the toughness of epoxy resin, hydroxyl-terminated polyethersulfone (PES) with various amounts (0 wt.%, 5 wt.%, 10 wt.%, 15 wt.%, 20 wt.%) were added to bisphenol A epoxy resin (DER331)/ curing agent DETDA (E100) systems, and the influence of PES contents on curing process and heat-resistance was studied. Non-isothermal DSC was used to determine the curing process of uncured DER331/E100/PES systems at heating rate of 2°C/min, 5°C/min, 7°C/min, 10°C/min and 15°C/min separately, and the apparent activation energy was calculated based on Kissinger method. The morphology of the etched cured DER331/E100/PES systems with different PES contents was observed by SEM. The heat-resistance of these systems was investigated by DSC and TGA. The results showed that with the increasing of PES content the curing exothermic peak, the heat of curing reaction, the initial and final curing temperature all decreased at the first and then increased, indicating that when the PES content was low (5 wt.%, 10 wt.%), PES can facilitate the curing process, while, when PES content up to 15 wt.%, PES can prevent or weaken the curing reaction. SEM results indicated that the phase structure changed drastically depending on the PES content. The systems with 5 wt.% and 10 wt.% PES were epoxy-rich phase, with 15 wt.% PES was co-continuity phase, and with 20 wt.% PES showed complete phase inversion (PES rich phase). The glass transition temperature and thermo gravimetric analysis demonstrated that the addition of PES can increase the heat resistance of cured DER331/E100/PES systems.

Study on the thermal stability of Controlled Permeability Formwork

2011 ◽  
Vol 374-377 ◽  
pp. 1426-1429
Author(s):  
Xiao Meng Guo ◽  
Jian Qiang Li ◽  
Xian Sen Zeng ◽  
De Dao Hong
Keyword(s):  
Thermal Stability ◽  
Thermal Properties ◽  
Dynamic Mechanical Analysis ◽  
Thermo Gravimetric Analysis ◽  
Mechanical Analysis ◽  
Gravimetric Analysis ◽  
Construction Work ◽  
Thermo Gravimetric ◽  
Excellent Thermal Stability ◽  
Thermal Stability Of

In this study, the thermal properties of a kind of new geotextile materials, so called controlled permeable formwork (CPF), were studied. Thermo-gravimetric analysis showed that the weight of CPF didn’t change much between 0~350 °C. Dynamic mechanical analysis showed that the storage modulus of CPF reduced from 25 MPa to around 10 MPa when the temperature rose to above 100 °C. The strength of sample decreased slightly with the increase of the temperature. The breaking elongation changed slightly with a maximum at 80 °C. The CPF showed excellent thermal stability and was suitable for general use in construction work.

Toughness and Thermal Properties of a Dimer Acid Modified Tetrafunctional Epoxy Resin

2015 ◽  
Vol 764-765 ◽  
pp. 107-110 ◽  
Author(s):  
Ming Ming Yu ◽  
Bin Feng ◽  
Min Yang ◽  
Li Qi Liu ◽  
Hong Li ◽  
...  
Keyword(s):  
Thermal Properties ◽  
Epoxy Resin ◽  
Thermo Gravimetric Analysis ◽  
Impact Resistance ◽  
Mechanical Analysis ◽  
Impact Testing ◽  
Gravimetric Analysis ◽  
Thermal Stabilities ◽  
The Impact ◽  
Tetrafunctional Epoxy

In order to improve the toughness of the cured aromatic tetrafunctional epoxy resins in the premise of influencing the thermal properties as little as possible, the aromatic tetrafunctional epoxy named N,N,N’,N’-tetraglycidyl-4,4’-diaminodiphenyl ether (TGDDE) was modified by a dimer carboxylic acid (DFA), and then the epoxies were cured with methyl nadic anhydride (MNA). In the present work, the toughness was characterized with the impact resistance tested by pendulum impact testing. Besides, the thermal properties of the cured epoxy resin were investigated with the thermo-gravimetric analysis (TGA) and dynamic mechanical analysis (DMA). The impact testing results indicated that the toughness of the cured resins could be improved after the modification and increased with the increasing content of DFA. The thermal analysis showed that the thermal properties of the cured resins were not influenced obviously since the thermal stabilities of the products could be improved and the glass transition temperature of them were not influenced obviously when the tetrafunctional epoxy modified with appropriate content of DFA.

scholarly journals Thermo-Gravimetric Analysis of Various Ratio of Blended Phenolic and Epoxy Composites

2019 ◽  
Vol 9 (1) ◽  
pp. 5435-5439 ◽  
Keyword(s):  
Thermal Properties ◽  
Epoxy Resin ◽  
Phenolic Resin ◽  
Thermo Gravimetric Analysis ◽  
Gravimetric Analysis ◽  
Optimum Ratio ◽  
Thermo Gravimetric ◽  
Residual Content ◽  
Very High ◽  
Phenolic Composite

Present research deals with the various ratio (0%, 40%, 50%, and 60% by wt%) of phenolic resin and epoxy resin blend composites. Phenolic resin/Epoxy resin blend composites were manufactured by hand lay-up technique and investigated the thermal properties (thermogravimetric analysis) of composites and evaluated optimum ratio of epoxy in phenolic composites. The residual content of pure phenolic was very high however the pure epoxy showed least thermal stable. After blending phenolic resin in epoxy resin, the thermal properties of epoxy/phenolic composite improved.

Dynamic Mechanical Analysis and Thermo-Gravimetric Analysis on Chopped Strand Mat Reinforced with Polyester Resin and Graphite Powder

2018 ◽  
Vol 1148 ◽  
pp. 48-60
Author(s):  
Pala Srinivas Reddy ◽  
T. Victor Babu ◽  
S. Santosh Kumar
Keyword(s):  
Dynamic Mechanical Analysis ◽  
Polyester Resin ◽  
Thermo Gravimetric Analysis ◽  
Graphite Powder ◽  
Mechanical Analysis ◽  
Gravimetric Analysis ◽  
Thermo Gravimetric ◽  
Dynamic Mechanical ◽  
Wide Range ◽  
Chopped Strand Mat

Fiber reinforced plastics have been widely used for manufacturing aircrafts and spacecrafts structural parts because of their high mechanical, physical properties. These are used in manufacturing of structural composites, printed circuit boards and in a wide range of special-purpose products which are included in medical field as well. Within reinforcing materials chopped strand mats are the most frequently used in structural constructions because of their properties such as viscoelasticity, strength and high thermal stability. The present work focuses on mechanical and thermal properties of chopped strand mat reinforced with polyester resin and filler as graphite powder (which has high melting point) in different weight fractions. Evaluation of material properties is tested using Thermo-Gravimetric Analysis and Dynamic Mechanical analysis at a standard temperature ranging between 20°C - 460°C and evaluated. The results show that inclusion of graphite powder in chopped strand mat exhibit better enhancement in results when compared.

Effects of Multi-Walled Carbon Nanotubes (MWCNTS) on the Mechanical and Thermal Properties of Plasticized Polylactic Acid Nanocomposites

2013 ◽  
Vol 812 ◽  
pp. 181-186 ◽  
Author(s):  
Maizatulnisa Othman ◽  
Kok Hui Tan ◽  
Hashim Mohd Yusof ◽  
Khalid Halisanni ◽  
Ghazali Ruzaidi ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Polylactic Acid ◽  
Flexural Properties ◽  
Mechanical And Thermal Properties ◽  
Dynamic Mechanical Analyzer ◽  
Roll Mill ◽  
Multi Walled Carbon Nanotube ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

A multi-walled carbon nanotube (MWCNT)/plasticized polylactic acid (PLA) composite was prepared using a two-roll mill set at 170°C and 50 rev/min. The material was characterized using dynamic mechanical analyzer (DMA). Characterization works include obtaining mechanical properties, such as tensile and flexural properties of the nanocomposites. Polyethylene glycol (PEG) at 6 wt% was used as the plasticizer for blending with the PLA. It was found that the tensile and flexural strengths of the nanocomposites increased up to 43.8 MPa and 81.4 MPa respectively with the addition of 0.15 wt% MWCNTs. The DMA results revealed that the storage modulus and the glass transition temperature (Tg) of the nanocomposites improved with the addition of 0.15 wt% CNTs, which was previously reduced by the incorporation of PEG.

MANUFACTURING AND CHARACTERIZATION OF CARBON NANOTUBE/POLYETHYLENE COMPOSITES

2005 ◽  
Vol 04 (01) ◽  
pp. 55-72 ◽  
Author(s):  
HASSAN MAHFUZ ◽  
ASHFAQ ADNAN ◽  
VIJAYA K. RANGARI ◽  
SHAIK JEELANI
Keyword(s):  
Carbon Nanotubes ◽  
Thermo Gravimetric Analysis ◽  
Extrusion Direction ◽  
Extrusion Process ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Neat Polymer ◽  
Single Screw Extrusion ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

The present study describes a method to fabricate polymer matrix nanocomposites by reinforcing multi-walled carbon nanotubes through an extrusion process. Linear low density polyethylene (LLDPE) powder and multi-walled carbon nanotubes (CNTs) are first dry mixed and extruded in the form of filaments by a single screw extrusion process. After extrusion, the filament is partially cooled by chilled air, dried, and continuously wound in a spool. The filaments are then laid in roving, stacked in a unidirectional fashion, and consolidated in a compression molding machine to come up with laminated composites. Thermo gravimetric analysis (TGA) has been performed to compare the thermal stability of as-fabricated composites with the neat polymer. The TGA result shows that the extruded composites are thermally more stable than their neat counterparts. The crystalline nature of CNTs and of as-fabricated composites were identified by X-ray diffraction (XRD) studies. The XRD results indicate that the nanocomposite materials are more crystalline than the neat systems, and the differential scanning calorimetry studies also confirmed the same trend. The scanning electron microscopy result showed that the sizes of extruded neat and nanophased filaments were about 117 and 73 μm, respectively. Tensile coupons from the consolidated panels were then extracted both in longitudinal (0°) and in transverse (90°) directions and tested in a Minimat Tester. It was found that with the addition of 2% by weight of CNTs in LLDPE, the tensile strength and modulus of the composite has increased by about 34 and 38%, respectively. The (0°) and (90°) coupons have also demonstrated that there are directional effects in the tensile response, which is believed to have been caused by the alignment of CNTs during the extrusion process. It is our understanding that such improvement in properties is because of the increase in crystallinity of the polymer due to CNT infusion, and also due to the alignment of CNTs in the extrusion direction in the nanocomposites. Details of the fabrication procedures, synthesis of composites, and mechanical testing are included in the paper.

Effect of maleic anhydride grafted polylactic acid concentration on mechanical and thermal properties of thermoplasticized starch filled polylactic acid blends

2021 ◽  
pp. 096739112110041
Author(s):  
Shakti Chauhan ◽  
N Raghu ◽  
Anand Raj
Keyword(s):  
Mechanical Properties ◽  
Thermal Properties ◽  
Maleic Anhydride ◽  
Polylactic Acid ◽  
Coupling Agent ◽  
Thermo Gravimetric Analysis ◽  
Mechanical Analysis ◽  
Strength Properties ◽  
Mechanical And Thermal Properties ◽  
Gravimetric Analysis

Polylactic acid (PLA) is blended with native starch or thermo plasticized starch (TPS) for preparing biodegradable composites. However, poor compatibility of PLA with starch results in the composites with inferior mechanical properties. This study examines the effect of Maleic Anhydride-Grafted-PLA (GMAPLA) coupling agent and its concentration on the extent of improvements in mechanical and thermal properties of PLA –TPS blends. Maleic anhydride was grafted on PLA in Haake torque rheometer, characterized and used as the coupling agent. PLA/TPS (wt/wt) blends (70/30 and 50/50) were prepared by twin screw extrusion. GMAPLA at three different levels 5%, 10% and 15% (wt%) with respect to PLA content was taken to study its effect on mechanical properties of blends. Presence of GMAPLA significantly improved the mechanical properties (tensile, flexural and impact strength) of TPS/PLA blends. Among the three concentrations, 10% GMAPLA in the blend was found to give the maximum improvement in strength properties. Dynamic mechanical analysis and thermo-gravimetric analysis indicated no significant effect of GMAPLA content on transition temperatures and thermal degradation behavior of the blends.

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