20.500.12556/DKUM-16781 IZBIRA MATERIALA ZA KONTROLO KAKOVOSTI POTENCIALA ZETA TRDNIH POVRŠIN MATERIALS SELECTION FOR THE ZETA POTENTIAL QUALITY-CONTROL OF SOLID SURFACES IZBIRA MATERIALA ZA KONTROLO KAKOVOSTI POTENCIALA ZETA TRDNIH POVRŠIN Povzetek Zanesljive rezultate meritev lahko zagotovimo le z brezhibnim delovanjem merilnih naprav, katerih zmogljivost pa se s časom in uporabo slabša. Pravilno delovanje merilne naprave lahko preverimo z referenčnim materialom. Tudi elektrokinetični analizator SurPASS, ki je na tržišču relativno kratek čas, je podvržen različnim vplivom in potrebuje material za kontrolo kakovosti potenciala zeta. Instrument SurPASS namreč omogoča merjenje pretočnega toka, s katerim določimo t.i. potencial zeta, ki določa stanje površinskega naboja na mejni površini trdnega telesa in tekočine. Izbire trdnega materiala z ravno površino, ki je primeren za merjenje v merilni celici CLC, smo se lotili z meritvami časovne odvisnosti potenciala zeta na polimerih (PTFE, PES in PET) ter steklu. Najbolj stabilne meritve dajeta vzorca PES in PET, ki sta glede na dobljene rezultate konstante hitrosti nabrekanja tudi najbolj hidrofobna. Zato smo meritve nadaljevali na teh dveh materialih. Statistična analiza rezultatov teh meritev nakazuje na homogenost obeh materialov, čeprav v nekaterih primerih daje prednost materialu PES, spet drugič PET. Takšne nasprotujoče si rezultate meritev lahko pripišemo tudi napakam v meritvah (omočenost nemerjene površine vzorca v CLC) in ne nujno nehomogenosti materiala. MATERIALS SELECTION FOR THE ZETA POTENTIAL QUALITY-CONTROL OF SOLID SURFACES Abstract Reliable results of measurements can only be assured by using faultless measuring instruments, the efficiencies of which do, regrettably, deteriorate over time and usage. The correct functioning of instruments can be examined using reference materials. The SurPASS electrokinetic analyser, which has only been on the market for a relatively short time, is also subject to different influences and therefore needs a material for zeta potential quality control. The SurPASS instrument enables the measurement of streaming-current which helps us to determine the so-called zeta potential, which then indicates the status of the surface-charge on the border area of a solid or liquid. We began by selecting a solid material with a flat surface, which would be suitable for the CLC measuring cell, using the measurements of time-dependence regarding zeta potential on polymers (PTFE, PES and PET), and glass. The more stable measurements were given for samples PES and PET, for which it provided the more constant results, and also the most hydrophobic materials. Consequently, we continued our measurements on the afore-mentioned two materials. Statistical analysis of these results indicated the homogeneities of both materials although, in some cases, it gave an advantage to PES, and then the second time to PET. These kinds of contradictive measurement results can also be annotated to mistakes during the measuring process (wettability of the non-measured surface sample in CLC), and not necessarily to any non-homogeneity of the material. Ključne besede: referenčni material polimerni materiali elektrokinetične lastnosti pretočni tok potencial zeta reference material polymeric materials electrokinetic properties streaming current zeta potential true true false [M. Rudaš] Slovenski jezik Angleški jezik Diplomsko delo 2010-11-19 11:15:04 2010-12-02 14:36:29 2022-04-13 08:54:11 2023-12-21 03:16:56 2010 0 Maribor 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 678.7:544.638(043.2) 15001878 URN:SI:UM:DK:EDFMWMYJ UNI_Rudas_Manuela_2010.pdf UNI_Rudas_Manuela_2010.pdf 1 A8BD0F5CF38CF0271AA20D1C53CE544B 3995ed88cb7e45299e9787a4c32fb05e1e30ce0f6a1194d606ee1b053a291d75 ba62fd96-7c04-11eb-bb7a-00155d0001ca 20.500.12556/dkum/bb4bb8db-7063-411f-b057-031659bc5588 https://dk.um.si/Dokument.php?lang=slv&id=19396 Fakulteta za kemijo in kemijsko tehnologijo 0 0 0