Melt processing of ethylene–vinyl acetate/banana starch/Cloisite 20A organoclay nanocomposite films: structural, thermal and composting behavior

Soft and conductive interfaces are valuable in wearable electronics as they are capable for integration of diverse classes of electronic and sensor technologies directly with living body which can be used as health monitoring systems. In present work, we explore the development of multi-walled carbon nanotube-ethylene vinyl acetate nanocomposite (MWCNT-EVA) film and their properties. Oxidation of MWCNT is known to improve their dispersion properties and increase the electrical conductivity of MWCNT-polymer nanocomposites. Thus, pristine MWCNTs (p-MWCNTs) and functionalized MWCNTs (f-MWCNTs) were further used as conductive filler to construct p-MWCNT-EVA and f-MWCNT-EVA nanocomposite films. The films were characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray analysis and electrochemical technique. The results indicated that the chemical oxidation of p-MWCNT generates carboxylic function at the p-MWCNT surface important for sensor fabrication. The concentration of carboxylic functional group in f-MWCNT higher than in nanocomposites. The f-MWCNT-EVA nanocomposite film electrode surface show much higher conductivitythan p-MWCNT-EVAnanocomposite film. Thus, the soft and flexible f-MWCNT-EVA nanocomposite films are effective for the development of electrochemical platform for biosensor fabrication in wearable applications.

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Structure–property relationship of halloysite nanotubes/ethylene–vinyl acetate–carbon monoxide terpolymer nanocomposites

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705715588802 ◽

2016 ◽

Vol 30 (1) ◽

pp. 121-140 ◽

Cited By ~ 10

Author(s):

Gibin George ◽

M Selvakumar ◽

Arunjunairaj Mahendran ◽

S Anandhan

Keyword(s):

Carbon Monoxide ◽

Vinyl Acetate ◽

Volume Resistivity ◽

Ethylene Vinyl Acetate ◽

Halloysite Nanotubes ◽

Filler Loading ◽

Nanocomposite Films ◽

Structure Property ◽

Ionic Charge ◽

Solution Cast

Poly(ethylene- co-vinyl acetate- co-carbon monoxide) (EVACO)/halloysite nanotube (HNT) nanocomposite films were solution cast. Dispersion of HNTs in the matrix was analyzed by elemental mapping and the role of HNTs on crystallizability, flammability and thermal, mechanical, and electrical properties of the polymer was evaluated. The nature of interaction between the EVACO matrix and HNTs was studied using Fourier transform infrared spectroscopy. The highest tensile strength was observed for the composite with 1% filler loading, whereas the highest crystallinity was observed for that with 3% filler loading. The decay in the tensile properties at higher filler loading was due to agglomeration of HNTs and debonding of polymer–filler interface. The electrical volume resistivity of the composites decreased with HNT loading because of the ionic charge transfer. The direct current electrical resistivity study of the composites proves that the addition of HNT can improve the antistatic properties of the polymer.

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Coupling Dynamic Covalent Bonds and Ionic Crosslinking Network to Promote Shape Memory Properties of Ethylene-vinyl Acetate Copolymers

Polymers ◽

10.3390/polym12040983 ◽

2020 ◽

Vol 12 (4) ◽

pp. 983 ◽

Cited By ~ 1

Author(s):

Wenjing Wu ◽

Sreeni Narayana Kurup ◽

Christopher Ellingford ◽

Jie Li ◽

Chaoying Wan

Keyword(s):

Tensile Strength ◽

Shape Memory ◽

Vinyl Acetate ◽

Mechanical Performance ◽

Memory Performance ◽

Ethylene Vinyl Acetate ◽

Crosslinking Density ◽

Melt Processing ◽

Covalent Bonds ◽

Shape Memory Properties

Dynamic crosslinking networks based on Diels–Alder (DA) chemistry and ionic interactions were introduced to maleic anhydride modified ethylene-vinyl acetate copolymer (mEVA) via in situ melt processing. The dual dynamic crosslinking networks were characterized by temperature-dependent FTIR, and the effects on the shape memory properties of mEVA were evaluated with dynamic mechanical thermal analysis and cyclic tensile testing. A crosslinking density was achieved at 2.36 × 10−4 mol·cm−3 for DA-crosslinked mEVA; as a result, the stress at 100% extension was increased from 3.8 to 5.6 MPa, and tensile strength and elongation at break were kept as high as 30.3 MPa and 486%, respectively. The further introduction of 10 wt % zinc methacrylate increased the dynamic crosslinking density to 3.74 × 10−4 mol·cm−3 and the stress at 100% extension to 9.0 MPa, while providing a tensile strength of 28.4 MPa and strain at break of 308%. The combination of reversible DA covalent crosslinking and ionic network in mEVA enabled a fixing ratio of 76.4% and recovery ratio of 99.4%, exhibiting an enhanced shape memory performance, especially at higher temperatures. The enhanced shape memory and mechanical performance of the dual crosslinked mEVA showed promising reprocessing and recycling abilities of the end-of-life products in comparison to traditional peroxide initiated covalent crosslinked counterparts.

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