Effects of Adding Multiwall Carbon Nanotubes on Performance of Polyvinyl Acetate and Urea-Formaldehyde Adhesives in Tropical Timber Species

Multiwall carbon nanotubes (MWCNTs) functionalized with hydroxyl groups (MWCNTs-OH) have been incorporated into polyvinyl acetate (PVAc) and urea-formaldehyde (UF) adhesives utilized in tropical wood gluing. The Raman spectroscopy, the atomic force microscopy (AFM), and transmission electron microscopy (TEM) were used to describe the MWCNTs-OH. The adhesives were evaluated in three concentrations of MWCNTs-OH: 0% (control), 0.05%, and 0.1%. The evaluation included color, the distribution of MWCNTs-OH by TEM and AFM, thermal stability and viscosity of the adhesives, and shear strength (SS) of the glue line for nine tropical woods. AFM and TEM confirmed interaction of MWCNTs-OH with adhesives. The viscosity of the PVAc adhesive increases with added MWCNTs-OH. The incorporation of MWCNTs-OH in PVAc and UF resin produces wood adhesives with less brightness, less yellowness, and increased redness. The nanotubes in the adhesive improved the thermal stability of the composites and increased the entropy factor and energy of activation in the kinetic decomposition of the resin. In relation to SS, MWCNTs-OH in any of the two concentrations had no significant effect on SS in dry condition in half of the species studied glued with PVAc adhesive, whereas, for UF-adhesive, the SS and percentage of wood failure improved in most of the 9 species studied.

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Composite Nanofibers Containing Multiwall Carbon Nanotubes as Biodegradable Membranes in Reconstructive Medicine

Nanomaterials ◽

10.3390/nano9010063 ◽

2019 ◽

Vol 9 (1) ◽

pp. 63 ◽

Cited By ~ 2

Author(s):

Andrzej Hudecki ◽

Dorota Łyko-Morawska ◽

Wirginia Likus ◽

Magdalena Skonieczna ◽

Jarosław Markowski ◽

...

Keyword(s):

Electron Microscopy ◽

Carbon Nanotubes ◽

Maxillofacial Surgery ◽

Multiwall Carbon Nanotubes ◽

Dermal Fibroblasts ◽

Hydroxyl Groups ◽

X Ray ◽

Biological Responses ◽

Transmission Electron ◽

Multiwall Carbon

We have tested titanium (Ti) plates that are used for bone reconstruction in maxillofacial surgery, in combination with five types of novel long-resorbable biomaterials: (i) PCL0—polycaprolactone without additives, (ii) PCLMWCNT—polycaprolactone with the addition of multiwall carbon nanotubes (MWCNT), (iii) PCLOH—polycaprolactone doped with multiwall carbon nanotubes (MWCNT) containing –OH hydroxyl groups, (iv) PCLCOOH—polycaprolactone with the addition of multiwall carbon nanotubes (MWCNT) containing carboxyl groups, and (v) PCLTI—polycaprolactone with the addition of Ti nanoparticles. The structure and properties of the obtained materials have been examined with the use of Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), and/or X-ray powder diffraction (XRD). Titanium BR plates have been covered with: (i) PCL0 fibers (PCL0BR—connection plates), (ii) PCLMWCNT fibers (PCLMWCNTBR—plates), (iii) PCLOH fibers (PCLOHBR—plates), (iv) PCLCOOH (PCLCOOHBR—plates), (v) PCLTI fiber (PCLTIBR—connection plates). Such modified titanium plates were exposed to X-ray doses corresponding to those applied in head and neck tumor treatment. The potential leaching of toxic materials upon the irradiation of such modified titanium plates, and their effect on normal human dermal fibroblasts (NHDF) have been assessed by MTT assay. The presented results show variable biological responses depending on the modifications to titanium plates.

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Thermal and Flame Retardant Properties of MWNT Reinforced Conductive PAN Film

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.924.253 ◽

2014 ◽

Vol 924 ◽

pp. 253-259

Author(s):

Zhuo Chen ◽

Xian Dong ◽

Wei Zhao ◽

Ke Jia Liu ◽

Ji Ping Liu

Keyword(s):

Carbon Nanotubes ◽

Thermal Stability ◽

Electrical Conductivity ◽

Composite Film ◽

Multiwall Carbon Nanotubes ◽

Ultrasonic Dispersion ◽

Vacuum Casting ◽

Ft Ir ◽

Flame Retardant Properties ◽

Multiwall Carbon

Conductive polyacrylonitrile film reinforced by multiwall carbon nanotubes was prepared via ultrasonic dispersion and vacuum casting. The structure of MWNT/PAN composite film was characterized by WAXD and FT-IR. The LOI of the blend was enhanced from 18.1 % to 24.5 % and TGA show better thermal stability. MWNT composite at 10 wt% MWNT loading showed an electrical conductivity of 10-2S/cm.

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PVA/MWNTs Composite Nanofibers Prepared by Electrospun

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.44-47.2377 ◽

2010 ◽

Vol 44-47 ◽

pp. 2377-2380

Author(s):

Hui Qin Zhang ◽

Ai Mei Li

Keyword(s):

Mechanical Properties ◽

Carbon Nanotubes ◽

Thermal Stability ◽

Fourier Transform ◽

Composite Nanofibers ◽

Multiwall Carbon Nanotubes ◽

High Energy ◽

Scanning Electronic Microscopy ◽

Electronic Microscopy ◽

Multiwall Carbon

The Polyvinyl alcohol (PVA)/ multiwall carbon nanotubes (MWNT) nanofibers were prepared by electrospun assisted by high-energy sonication. The morphological structures and characterized of the nanofibers were observed via scanning electronic microscopy (SEM), thermogravimetric analysis (TGA) and Fourier transform infrared (FTIR). Electrical properties and mechanical properties of the film have been tested. The results indicate that the introduction of ATO nanoparticles into the polymer matrix has a significant effect on the thermal stability properties of PVA and a strong interaction between PVA and MWNTs.

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Thermal stability of bidendate nitrogen ligands tethered to multiwall carbon nanotubes

Journal of Thermal Analysis and Calorimetry ◽

10.1007/s10973-010-0774-0 ◽

2010 ◽

Vol 102 (2) ◽

pp. 505-512 ◽

Cited By ~ 1

Author(s):

Bob A. Howell ◽

Adina Dumitrascu

Keyword(s):

Carbon Nanotubes ◽

Thermal Stability ◽

Multiwall Carbon Nanotubes ◽

Nitrogen Ligands ◽

Multiwall Carbon ◽

Thermal Stability Of

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Effect of MWNTs and SiC-Coated MWNTs on Properties of PEEK/LCP Blend

Journal of Nanotechnology ◽

10.1155/2009/759374 ◽

2009 ◽

Vol 2009 ◽

pp. 1-6 ◽

Cited By ~ 5

Author(s):

Ganesh Chandra Nayak ◽

R. Rajasekar ◽

Saswata Bose ◽

Chapal Kumar Das

Keyword(s):

Carbon Nanotubes ◽

Thermal Stability ◽

Silicon Carbide ◽

Tensile Strength ◽

Glass Transition ◽

Transition Temperature ◽

Multiwall Carbon Nanotubes ◽

Tensile Modulus ◽

Melt Blending ◽

Multiwall Carbon

Multiwall carbon nanotubes (MWNTs) were modified with polycarbosilane-derived silicon carbide (SiC) to improve its dispersion in the polymer matrix. PEEK/LCP/MWNTs nanocomposites were prepared by melt blending. TEM images show the improved dispersion of SiC-coated MWNTs against agglomerated structure of pure MWNTs in the blend. FESEM images shows better fibrillation of LCP in presence of SiC-coated MWNTs. TGA reveals that nanocomposites with SiC-coated MWNTs shows higher thermal stability than MWNTs filled blend system. Based on enhanced dispersion, storage modulus, tensile modulus and tensile strength were increased drastically with the incorporation of SiC-coated MWNTs. Glass transition temperature of the nanocomposites shows significant improvement with the incorporation of MWNTs.

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Boehmite Nanofibers as a Dispersant for Nanotubes in an Aqueous Sol

10.26434/chemrxiv.6652955.v1 ◽

2018 ◽

Author(s):

Gen Hayase

Keyword(s):

Carbon Nanotubes ◽

Aspect Ratio ◽

Aqueous Solutions ◽

High Aspect Ratio ◽

Multiwall Carbon Nanotubes ◽

Multiwall Carbon ◽

Nanotube Films

By exploiting the dispersibility and rigidity of boehmite nanofibers (BNFs) with a high aspect ratio of 4 nm in diameter and several micrometers in length, multiwall-carbon nanotubes (MWCNTs) were successfully dispersed in aqueous solutions. In these sols, the MWCNTs were dispersed at a ratio of about 5–8% relative to BNFs. Self-standing BNF–nanotube films were also obtained by filtering these dispersions and showing their functionality. These films can be expected to be applied to sensing materials.

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