Determination of the particle interactions rheology-suface roughness relationship for dental ceramics
tarafından
 
Kes, Mürşide.

Başlık
Determination of the particle interactions rheology-suface roughness relationship for dental ceramics

Yazar
Kes, Mürşide.

Yazar Ek Girişi
Kes, Mürşide.

Yayın Bilgileri
[s.l.]: [s.n.], 2007.

Fiziksel Tanımlama
xiv, 111 leaves.: ill.+ 1 computer laser optical disc.

Özet
In this study, relationship between particle interactions, rheology and surface roughness for dental ceramics was determined. For this purpose IPS Empress 2 veneer powder was chosen and characterized with XRD, SEM, EDS, Zeta Potential and Particle Size measurements.Particle interactions have been interpreted in the light of DLVO Theory for distilled water and electrolyte solutions at different concentrations (0.1, 0.25, 0.5, 0.75,1 M NaCl and CaCl2). The results indicated that interactions between particles change with electrolyte concentration and valency. Electrical Double Layer Thickness (Debye Length) compresses and Energy Barrier height decreases as electrolyte concentration and valency increase mean that there is agglomeration between particles. In order to understand the rheological properties of the system shear rate versus shear stress and shear rate versus viscosity graphs were interpreted for the same environmental conditions, distilled water and electrolyte solutions at different concentrations. It was obtained that at low electrolyte conditions particles formed agglomerates, however at high electrolyte conditions the system reached equilibrium where particles formed gel structures due to their non-Newtonian behaviour.The results obtained from rheological measurements were compared with the results obtained from AFM, profilometer and SEM measurements for the surfaces prepared with IPS Empress 2 veneer powder and it was concluded that in the presence of electrolytes (Na+ and Ca2+) surface roughness increased at low concentrations due to agglomeration of particles whereas surface roughness decreased at high concentrations most probably due to gelation in the system. Moreover, this situation was supported with contact angle measurements where contact angle mean values are high and ditributions are wide at low electrolyte concentrations while contact angle mean values are small and distributions are narrow at high concentrations

Konu Başlığı
Dental ceramics.
 
Rheology.
 
Surface roughness.
 
Particles.

Yazar Ek Girişi
Polat, Hürriyet

Tüzel Kişi Ek Girişi
İzmir Institute of Technology. Chemistry.

Tek Biçim Eser Adı
Thesis (Master)--İzmir Institute of Technology: Chemistry.
 
İzmir Institute of Technology: Chemistry--Thesis (Master).

Elektronik Erişim
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LibraryMateryal TürüDemirbaş NumarasıYer NumarasıDurumu/İade Tarihi
IYTE LibraryTezT000623RK655 .K42 2007Tez Koleksiyonu