Electrospun Polymer/MWCNTs Nanofiber Reinforced Composites “Improvement of Interfacial Bonding by Surface Modified Nanofibers”

2009 ◽  
Vol 1224 ◽  
Author(s):  
Elif Ozden ◽  
Yusuf Ziya Menceloglu ◽  
Melih Papila
Keyword(s):  
Storage Modulus ◽  
Mechanical Response ◽  
Crosslinking Agent ◽  
Weight Fraction ◽  
Crosslinking Density ◽  
Interfacial Bonding ◽  
Reinforced Composites ◽  
Multi Walled Carbon Nanotubes ◽  
Surface Modified ◽  
Walled Carbon Nanotubes

AbstractIn-house synthesized copolymers Polystyrene-co-glycidyl methacrylate (PSt-co-GMA) are electrospun as mat of surface modified nanofibers with and without multi walled carbon nanotubes (MWCNTs). Composites are then formed by embedding layers of the nanofiber mats into epoxy resin. Interfacial bonding between polymer matrix and the nanofibers, and surface modification driven enhancement in mechanical response is assessed under flexural loads. Results indicate that at elevated temperture storage modulus of epoxy reinforced by PSt-co-GMA nanofibers and PSt-co-GMA/ MWCNTs composite nanofibers is about 10 and 20 times higher than the neat epoxy, respectively, despite weight fraction of the nanofibers being as low as 2%. Interfacial interaction is revealed by the storage modulus comparison of unmodified Polystyrene (PSt) and modified PSt-co-GMA nanofiber reinforced composite. To enhance further the resulting “crosslinked” structure, crosslinking agent ethylenediamine is also sprayed on the nanofibrous mats. Increased crosslinking density improves mechanical response of sprayed-over PSt-co-GMA nanofibers reinforced composites which is about 4 times higher than plain PSt-co-GMA nanofibers.

Cure and Dynamic-Mechanical Behaviors of Vinyl Ester Resinfilled with Multi-Walled Carbon Nanotubes

2010 ◽  
Vol 150-151 ◽  
pp. 1413-1416 ◽  
Author(s):  
Hong Yan Chen ◽  
Zhen Xing Kong ◽  
Ji Hui Wang
Keyword(s):  
Carbon Nanotubes ◽  
Vinyl Ester ◽  
Mechanical Response ◽  
Cure Kinetics ◽  
Crosslinking Density ◽  
Vinyl Ester Resin ◽  
Scanning Calorimetry ◽  
Dynamic Mechanical ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

The cure kinetics of Derakane 411-350, a kind of vinyl ester resin, and its suspensions containing multi-walled carbon nanotubes( MWCNTs) were investigated via non-isothermal dynamic scanning calorimetry (DSC) measurements. The results showed that incorporation of MWCNTs into vinyl ester resin excessively reduces polymerization degree and crosslinking density of vinyl ester resin. For suppressing the negative effect caused by nanotubes, the higher temperature initiator combined with the initiator MEKP was used. Dynamic-mechanical Behavior testing was then carried out on the cured sample in order to relate the curing behavior of MWCNTs modified resin suspensions to mechanical response of their resulting nanocomposites. It was revealed that nanocomposites containing MWCNTs possessed larger storage modulus values as well as higher glass transition temperatures (Tg) as compared to those without MWCNTs after using mixed intiators system to improve the degree of cure.

Dynamic Thermo-Mechanical Properties of Chemically Surface Modified MWCNTs Reinforced Polymeric Composites

2007 ◽  
Vol 26-28 ◽  
pp. 285-288 ◽  
Author(s):  
Abu Bakar Sulong ◽  
Joo Hyuk Park
Keyword(s):  
Mechanical Properties ◽  
Storage Modulus ◽  
Polymeric Composites ◽  
Matrix Composites ◽  
Chemical Surface ◽  
Dynamic Mechanical Thermal Analyzer ◽  
Thermal Analyzer ◽  
Multi Walled Carbon Nanotubes ◽  
Surface Modified ◽  
Walled Carbon Nanotubes

The dynamic thermo-mechanical properties of two types of chemically surface modified (Carboxylated and Octadecylated) multi-walled carbon nanotubes (MWCNTs) and As produced MWCNTs reinforced epoxy matrix composites are investigated by Dynamic Mechanical Thermal Analyzer at 1.0 wt% concentration. Moreover, influence of MWCNTs concentration variations to the dynamic thermo-mechanical properties are evaluated at Carboxylated MWCNT reinforced polymeric composites (from 0.1 to 5.0 wt %). Higher interfacial bonding strength is achieved by introducing the chemical surface modification. Also MWCNTs reinforced polymer shows higher storage modulus (from 30°C to 70°C) than pure polymer. Moreover, the storage modulus of composites increases linearly by increasing MWCNTs concentration. However, glass transition temperature (Tg) of composites decreases linearly by increasing MWCNTs concentration.

A strategy for improving peroxidase stability via immobilization on surface modified multi-walled carbon nanotubes

2015 ◽  
Vol 90 (9) ◽  
pp. 1570-1578 ◽  
Author(s):  
Renato M Azevedo ◽  
João B Costa ◽  
Philippe Serp ◽  
José M Loureiro ◽  
Joaquim L Faria ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Multi Walled Carbon Nanotubes ◽  
Surface Modified ◽  
Walled Carbon Nanotubes

Pebax-1657 mixed matrix membrane containing surface modified multi-walled carbon nanotubes for gas separation

RSC Advances ◽  
2016 ◽  
Vol 6 (83) ◽  
pp. 79563-79577 ◽  
Author(s):  
S. A. Habibiannejad ◽  
A. Aroujalian ◽  
A. Raisi
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Functional Groups ◽  
Gas Separation ◽  
Mixed Matrix Membrane ◽  
Mixed Matrix ◽  
Multi Walled Carbon Nanotubes ◽  
Surface Modified ◽  
Walled Carbon Nanotubes

In this study different functional groups on the surface of carbon nanotube enhanced the performance of Pebax 1657/MWNTs.

Nucleating effect of surface modified MWNTs on crystallization of MWNTs/PA6 composites

e-Polymers ◽  
2010 ◽  
Vol 10 (1) ◽  
Author(s):  
Juan Li ◽  
Qun Gu ◽  
Xinyu Fan ◽  
Zhenghong Guo ◽  
Zhengping Fang
Keyword(s):  
Polyamide 6 ◽  
Surface Characteristic ◽  
Crystalline Form ◽  
Scanning Calorimetry ◽  
Amino Functionalization ◽  
Before And After ◽  
Multi Walled Carbon Nanotubes ◽  
Surface Modified ◽  
Walled Carbon Nanotubes ◽  
Nucleating Effect

AbstractThe surface characteristic of multi-walled carbon nanotubes (MWNTs) plays an important role in the crystallization of polyamide 6 (PA6). In this paper, 1,6-hexamethylenediamine(HMD) are grafted on MWNTs. The MWNTs before and after modification are used to fabricate PA6 composites through melt-blending. The nucleating effect of MWNTs with different surface characteristic is investigated by differential scanning calorimetry (DSC), polarized optical microscopy (POM) and Xray diffraction (XRD).The heterogeneous nucleating ability of MWNTs determined by the Dobreva method are higher for pristine than amine-functionalized MWNTs/PA6 composites with 1.0 wt% MWNTs. Addition of MWNTs induce more heterogeneous nucleation and retards the crystal growth of PA6. The presence of MWNTs facilitates the formation of α crystalline form, while amino-functionalization weakens this trend. MWNTs act as effective nucleation agents for PA6, resulting in the increased number and decreased size of spherulites. MWNTs facilitate the formation of α crystalline form of PA6. Amino-functionalization decreases the crystallization and nucleating effect of MWNTs on PA6

Characterization of Vinyl Ester/Jute Fiber Bio-Composites in the Presence of Multi-Walled Carbon Nanotubes

2017 ◽  
Vol 730 ◽  
pp. 221-225
Author(s):  
Mohamed Bassyouni ◽  
Shereen M.S. Abdel-Hamid ◽  
Mohamed H. Abdel-Aziz ◽  
M.Sh. Zoromba
Keyword(s):  
Carbon Nanotubes ◽  
Storage Modulus ◽  
Vinyl Ester ◽  
Loss Modulus ◽  
Weight Ratio ◽  
Mechanical Analysis ◽  
Jute Fiber ◽  
Multi Walled Carbon Nanotubes ◽  
Fiber Reinforcements ◽  
Walled Carbon Nanotubes

In this study, vinyl ester –Jute fiber biocomposites were prepared using vacuum-assisted resin infusion (VARI) process. Woven Jute fibers were used with mass fraction 0.68. Multi-walled carbon nanotubes (MWCNTs) are added to the resin with weight ratio 0.5: 99.5 to investigate the thermo-mechanical properties of bio-composites. Storage and loss modulus of vinyl ester bio-composites were investigated in the presence MWCNTs over a range of temperature (25 to 160 oC) to measure the capacity of bio-composite to store and dissipate energy. Damping properties of vinyl ester bio-composites were studied in terms of tan (d). Viscoelastic test using dynamic mechanical analysis (DMA) showed that the glass transition temperature increases with the addition of MWCNTs up to 112.4 oC. Addition of jute fiber reinforcements improves the storage modulus value of vinyl ester more than 65% at room temperature. Significant improvement in storage modulus was found in the presence of MWCNTs.

scholarly journals Covalent Immobilization of Tyrosinase onto Multi-walled Carbon Nanotubes and Its Potential Use In Phenol Biosensing

2014 ◽  
Vol 7 (1) ◽  
Author(s):  
Shafinaz Shahir ◽  
Boon Kai Tai ◽  
Zaiton Abdul Majid ◽  
Nor Aziah Buang
Keyword(s):  
Carbon Nanotubes ◽  
Covalent Immobilization ◽  
Limiting Current ◽  
Reduction Peak ◽  
Covalently Bonded ◽  
Amide Carbonyl ◽  
Multi Walled Carbon Nanotubes ◽  
Surface Modified ◽  
Walled Carbon Nanotubes ◽  
Functionalized Mwcnts

The possibility of modifying the surface properties of multi-walled carbon nanotubes (MWCNTs) has stimulated increasing interest in their application as components in biosensors. In this sense, it is possible to employ surface modified MWCNTs as support to immobilize biomaterials such as enzymes. In this study the enzyme tyrosinase was immobilized onto functionalized MWCNTs (fMWCNTs) via covalent bonding and activity of immobilized tyrosinase was measured via electrochemical detection of phenol. MWCNTs were first treated with sulphuric acid and nitric acid with ratio 1 : 3 at 70ºC to introduce carboxylated groups (-COOH). The carboxyl moieties were then activated by treatment with a cross-linker, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) to enable tyrosinase immobilization via amide bonding. FTIR spectra of tyrosinase immobilized fMWCNTs showed the presence of peaks attributing to aliphatic C-N (1382 cm-1) and amide carbonyl (1639 cm-1) vibrations which confirmed successful covalent immobilization of tyrosinase onto fMWCNTs. Electrochemical measurements using tyrosinase-fMWCNTS-CPE revealed increasing limiting current values of reduction peak with increasing phenol concentrations at -200mV. The appearance of the reduction current indicates that the immobilization process retained the biological activity of the covalently bonded tyrosinase on fMWCNTs surface. This study has demonstrated the potential of using MWCNTs as support for enzyme immobilization and their application in biosensor technology.

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