الفهرس 
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Abstract
Nanotechnology refers to the science and engineering of particles that are on the
nanoscale, which is about 1 to 100 nanometers (nm) in size. For comparison, the thickness of
a sheet of paper is about 100,000 nm and the width of a hair.
Materials that exhibit a dimension below 100nm have very different and interesting
properties than its bulk material. With opportunities ranging from aerospace and defense to
medical to sporting goods, nanotechnology will change the face of innovation for generations
to come.
Addition of nanotubes could acquire biomedical composites biomaterials with distinct
performances in lots of areas. Nanofillers are very different from traditional fillers largely
because of their scale in nanometers and special microstructure, and we could make a
substantial increase in the mechanical properties of medical composites biomaterials by
means of nontechnology.
One way to conquer the current flaws of medical composite biomaterial, fillers in
forms of nanofibers or nanotubes are the most promising fillers to raise the mechanical
performances of composite Biomaterials tremendously at a low content. We also make a
general understanding of potential reinforced bonding mechanism, the reinforcement effect
which greatly depends on nanofillers` toughness (which is the material ability to absorb
energy and plastically deforms without fracturing in Energy per Unit Volume) , the condition
of nanofillers` dispersion in the body, and powerful bonding between nanofillers (in forms of
nanofibers and nanotubes) and matrix.
According to the previous statements, this thesis is an attempt to investigate the
opportunity of using carbon nanotubes in medical biomaterial applications.
The experiments attempt to improving a biomedical composite biomaterial by adding
multiwall carbon nanotubes as nanofillers have ended up to a non positive results, since they
produced a black composite material without any improvement in the physical or mechanical
properties, (barley, a significant decrease in the composite Young`s modulus, and a poor non
significant increase in mechanical properties) which is the opposite of the predicted desired
results.
In this review, the efforts using carbon nanotubes to enhance the mechanical
performance of biomedical composite (4% HA+ 96% GIC), as well as their physical research
related, were done in the following there phases sequence:
Phase I: Materials characterizations:
1. Fourier Transform Infrared spectroscopy (FTIR).
2. Particle size analyzer (PSA).
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3. X-ray diffraction (XRD).
4. Transmission electron microscope (TEM).
5. Scan electron microscope (SEM).
Phase II: Physical Properties study.
1. Color change comparison.
2. Weight loss measurements.
3. Dielectric measurements.
Phase III: Mechanical Properties study.
1. Compressive strength test (CS).
2. Diametral tensile strength test (DTS).
3. Microhardness test (Vickers test).
5.2. CONCLUSION
5.2.1. Adding different ratios of nanocarbon to a composite of (4% HA + 96% GIC):
The mixture resulted in a black composite material without any improvement in the
physical or mechanical properties.
For the compression strength CS, the best results were at a CNTs weight ratio of 2%.
At this optimum ratio, only a slight increase in compressive strength from 138.97
MPa at control group to 144.73 MPa which can’t be remarked as a significant
improvement in the compressive strength.
At the same ratio, the young`s modulus slightly decreases from 32.78 MPa at control
group to 30.66 MPa which also can’t be remarked as a significant change in the
composite elasticity.
Overall, increase the weight ratio of CNTs added to the main original composite
resulted in a sharp decrease in the composite compression strength from 144.73 MPa
at 2% CNTs to 84.74 MPa at 5% CNTs, and also resulted in sharp increase in the
elasticity of the composite (Young’s` modulus) from 30.66 MPa at 2% CNTs to 14.54
MPa at 5% CNTs.
For the Diametral tensile strength DTS, the best results were at a CNTs weight ratio
of 3%. At this optimum ratio, adding the CNTs almost kept the same diametral tensile
strength of control group (12.5 and 12.65 MPa) respectively, which can’t represent
any improvement in the diametral tensile strength at all.
while the young`s modulus at the DTS had a significant development from 7.44 MPa
at control group to 3.82 MPa at this optimum DTS CNTs ratio.
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For the Different mixing methods in both CS and DTS, comparing the mean stress
results of the Sonication mixing and Vibration mixing methods cleared that mixing
differentiated density materials is not a suitable method as the materials separated
later depending on its density through the critical fluid media while its evaporation.
And in the present study, the very low-density CNTs separated from the mixture just
after the Sonication process and before the full alcohol evaporation and formed a thin
surface layer on the mixture.
This result was noticed during the comparison of the CS results at 5% CNTs weight
ratio at Sonication and Vibration groups (15.92 and 84.74 MPa) respectively.
The same was noticed during the DTS results at 5% CNTs weight ratio at Sonication
and Vibration groups (5.9 and 12.5 MPa) respectively.
For the Physical properties, after adding the different ratios of CNTs to samples
groups, three of the physical properties were checked (color, Weight loss, and
Electrical properties)
About the color, adding any ratio CNTs to the control group changed the samples
from A2 and B2 colors to totally black color whatever the adding ratio is (from 1% to
10% of CNTs)