Naslov
Adsorption of Polyacrylic Acid on Aluminium Oxide and Silicon Carbide

Autori
Marković, Berislav

Vrsta, podvrsta i kategorija rada
Ocjenski radovi, doktorska disertacija

Fakultet
Prirodoslovno-matematički fakultet

Mjesto
Zagreb

Datum
17.04

Godina
1996

Stranica
110

Mentor
P. Somasundaran

Neposredni voditelj
N. Kalay

Ključne riječi
alumina; particle porosity; polyacrylic acid; polymer adsorption; silicon carbide
(alumina; particle porosity; plyacrylic acid; polymer adsorption; silicon darbide)

Sažetak
Polymer adsorption on mineral surface is of importance in a variety of industrial applications. Even though it has been studied widely, there is a need for systematic investigation of the effect of polymer molecular weight and mineral surface porosity on adsorption processes. Polymers used to control the dispersion properties of slurries are generally polydispersed and particle surface is seldom non-porous and homogeneous. Adsorption of polyacrylic acid of different molecular weight on alumina particles of same mineralogical composition but different porosity was studied under various pH conditions. It was found that polymer adsorption density increases with increasing polymer molecular weight if the particle surface is non-porous. However, when alumina particles are highly porous, polymer adsorption density decreases markedly with increasing polymer molecular weight at pH<7. Under higher pH conditions, when polymer conformation in solution is in "stretched" form, the differences in adsorption plateau values for all polymer molecular weight studied become negligible. Polymer adsorption kinetics and influence of adsorption on particle surface charge was also studied. Adsorption experiments and surface charge measurements were conducted on silicon carbide platelets as well. A correlation of particle pore sizes and calculated polymer molecule size has been established. This correlation exists only under acidic suspension conditions (when polyacrylic acid is mainly non-ionized), when the accessible surface area is actually changing, depending upon polymer molecule size.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

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