Reinforcement of Hydroxyapatite with Multi-Walled Carbon Nanotubes

2011 ◽  
Vol 306-307 ◽  
pp. 72-75 ◽  
Author(s):  
Zhi Hua Lu ◽  
Kang Ning Sun ◽  
Dong Mei Zhao

Multi-walled carbon nanotubes (MWNTs) reinforced hydroxyapatite (HA) composite was fabricated by in-situ method and followed by hot-pressing sintering; the influence of MWNTs’ content on the mechanical and microstructure properties was explored. The results show that adding MWNTs within a certain range could enhance the mechanical properties of HA matrix significantly. The maximal increment of the bending strength and fracture toughness of the composites, compared with the pure HA, were 157% and 171% respectively. XRD and TEM showed that the primary crystal phase of the composite was HA together with the diffraction peaks of carbon nanotube. By SEM, we found that MWNTs are homogeneously dispersed within grains or at grain boundaries of the HA matrix in composites which MWNTs’ content was not more than 15vol%, otherwise MWNTs tended to be agglomerated. The reinforcement mechanism was discussed based on the microstructure investigation. The broken nanotubes and pullout of MWNTs at interfaces were efficient in transferring the load from the HA matrix to the nanotubes, leading to the improvement of the mechanical properties.

2011 ◽  
Vol 236-238 ◽  
pp. 2063-2066
Author(s):  
Xian Kai Jiang ◽  
Ji You Gu ◽  
Yan Hua Zhang

Mechanical properties of polyurethane coating were improved by multi-walled carbon nanotubes (MWNTs) via in situ polymerization and blending polymerization. Fourier transform infrared spectroscopy (FT-IR) measurement was employed to assess the influence of acid treatment on MWNTs. Mechanical properties analysis of polyurethane coatings including tensile strength, elastic modulus, hardness, flexibility, impact resistance were employed to assess the improvement of mechanical properties of polyurethane coating by MWNTs. The results indicated that MWNTs could improve the mechanical properties of polyurethane coatings, and the improvement of polyurethane coatings by MWNTs via in situ polymerization were better than via blending polymerization, and the improvement of polyurethane coatings by acid-treated MWNTs were better than by raw MWNTs.


2014 ◽  
Vol 893 ◽  
pp. 241-244
Author(s):  
Yong Hui Lv ◽  
Bao Xiang Deng

The acidified multi-walled carbon nanotubes (MWNTs-COOH) was obtained by nitric acid treatment on multi-walled carbon nanotubes (MWNTs).The PI/MWNTs-COOH composite films were synthesized by in situ polymerization. The thermal stability, resistance and mechanical properties of PI/MWNTs-COOH composite were evaluated. The results showed that: the composites maintained a good thermal stability with the addition of the MWNTs-COOH; the resistance of the composite film dropped at first, and rose up later. While the tensile strength increased at first and then decreased. In conclusion, the PI/MWNTs-COOH composite films exhibited better thermal, antistatic and mechanical properties compared with neat PI.


2016 ◽  
Vol 70 (6) ◽  
Author(s):  
Agnieszka Piegat ◽  
Anna Jędrzejewska ◽  
Robert Peƚech ◽  
Iwona Peƚech

AbstractThe influence of the chemical modification of carbon nanotubes on the mechanical, thermal and electrical properties of poly(butylene terephthalate)-based composites was investigated. Polymer composites based on poly(butylene terephthalate) were obtained via in situ polymerisation or extrusion. Commercially available multi-walled carbon nanotubes (Nanocyl NC7000) at different loadings (mass %: 0.05, 0.25, 1, 2) were used as fillers. The functionalisation process took place under a chlorine atmosphere followed by a reaction with sodium hydroxide. The effect of carbon nanotube modification was analysed according to the changes in the polymer thermal and mechanical properties. An addition of modified carbon nanotubes in the amount of 0.05 mass % improved the mechanical properties of the composites in terms of both Young’s modulus and tensile strength by 5–10 % and 17–30 % compared with composites with unmodified carbon nanotubes and neat poly(butylene terephthalate), respectively. The in situ method of composite preparation was a more effective technique for enhancing the matrix–filler interactions, although a significantly lower amount of fillers were used than in the extrusion method.


2012 ◽  
Vol 573-574 ◽  
pp. 1163-1166
Author(s):  
Shi Yun Li ◽  
De Sheng Hu

The MWNTs/PE nanocomposites are prepared by in situ polymerization with mulltiwalled carbon nanotubes (MWNTs) supported Cp2ZrCl2 catalyst and MAO as cocatalyst. The SEM and AFM results show that MWNTs are exfoliated and homogenously dispersed in PE matrix by the in situ polymerization. The up-shifting of the G band in Raman spectra show the strong compressive forces associated with PE chains on the MWNTs. The storage modulus of the MWNTs/PE nanocomposite can be increased by 160% even at low amount of MWNTs (0.2 wt %) due to MWNTs well-dispersed and exfoliated in the matrix. The TGA and DMA tests point to significant improvements on thermal and mechanical properties of the PE/MWNTs nanocomposites compared to pure PE.


RSC Advances ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 1109-1114
Author(s):  
Peng Lv ◽  
Yeyun Meng ◽  
Lingxia Song ◽  
Hao Pang ◽  
Weiqu Liu

A robust self-supported electrode was prepared by a facile combination of ultrasonic dispersion and consequent in situ polymerization.


2021 ◽  
Author(s):  
Shankar S. Narwade ◽  
Shivsharan M. Mali ◽  
Bhaskar R. Sathe

A study on the in situ decoration of ethylenediamine (EDA) on acid functionalized multi-walled carbon nanotubes (O-MWCNTs) for overall water splitting reactions at all pH as an efficient and inexpensive metal-free multifunctional electrocatalyst.


2021 ◽  
Vol 3 (6) ◽  
Author(s):  
Seyed Ali Mirsalehi ◽  
Amir Ali Youzbashi ◽  
Amjad Sazgar

AbstractIn this study, epoxy hybrid nanocomposites reinforced by carbon fibers (CFs) were fabricated by a filament winding. To improve out-of-plane (transverse) mechanical properties, 0.5 and 1.0 Wt.% multi-walled carbon nanotubes (MWCNTs) were embedded into epoxy/CF composites. The MWCNTs were well dispersed into the epoxy resin without using any additives. The transverse mechanical properties of epoxy/MWCNT/CF hybrid nanocomposites were evaluated by the tensile test in the vertical direction to the CFs (90º tensile) and flexural tests. The fracture surfaces of composites were studied by scanning electron microscopy (SEM). The SEM observations showed that the bridging of the MWCNTs is one of the mechanisms of transverse mechanical properties enhancement in the epoxy/MWCNT/CF composites. The results of the 90º tensile test proved that the tensile strength and elongation at break of nanocomposite with 1.0 Wt.% MWCNTs improved up to 53% and 50% in comparison with epoxy/CF laminate composite, respectively. Furthermore, the flexural strength, secant modulus, and elongation of epoxy/1.0 Wt.% MWCNT/CF hybrid nanocomposite increased 15%, 7%, and 9% compared to epoxy/CF laminate composite, respectively.


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