Dimerne površinski aktivne tvari s dvovalentnim prijelaznim metalima

undergraduate thesis

• Title (english): Self-assembly of dimeric metallosurfactants
• Author: Leona Zagorec
• Mentor: Jelena Macan (mentor)
• Committee member: Jelena Macan (predsjednik povjerenstva)
• Committee member: Danijela Ašperger (član povjerenstva)
• Committee member: Vesna Ocelić Bulatović (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2023-09-12, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract

Cilj ovog rada bio je utvrditi utjecaj dvovalentnih prijelaznih metala u protuionu dimerne površinski aktivne tvari (PAT), bis(N,N-dimetil-N-dodecil)etilen-1,2-diamonijevog dibromida, na njezina osnovna fizikalno-kemijska svojstva. U tu svrhu sintetizirane su nove dimerne PAT koje u protuionu sadrže metalni ion kobalta, bakra ili cinka te su označene kao [MBr4](dim) (M = Co, Cu, Zn). Dimerne PAT već desetljećima privlače veliku pažnju istraživača jer usporedbe fizikalno-kemijskih svojstava pokazuju da su znatno superiornije od monomernih u svim svojstvima na kojima se temelji njihova upotreba. Uvođenjem metalnih iona u njihovu strukturu nastaju jedinstveni spojevi koji osim sposobnosti adsorpcije i asocijacije posjeduju redoks, magnetska, i katalitička svojstva. Otopine novosintetiziranih PAT istražene su mjerenjem površinske napetosti Du Noüyevom metodom, mjerenjem električne provodnosti, a veličina i zeta-potencijal micela određeni su dinamičkim (DLS) i elektroforetskim raspršenjem svjetlosti (ELS). Utvrđeno je da se površinska aktivnost dimernih PAT zamjenom uobičajenog halogenog Br- protuiona s kompleksnim [MBr4]2- povećava, a vrijednosti kritične micelizacijske koncentracije (cmc) se pomiču prema manjim koncentracijama. Također, DLS rezultati pokazali su da sve [MBr4](dim) PAT pri istim koncentracijama asociraju u cilindrične i veće micele u odnosu na polaznu dimernu PAT. Razlike u fizikalno-kemijskim svojstvima unutar novosintetizirane serije PAT nisu jako izražene i više-manje su neovisne o vrsti metalnog iona.

Abstract (english)

The aim of this investigation was to give better insight into the structure-property relationships of dimeric metallosurfactants. Using
bis(N,N-dimethyl-N-dodecyl)ethylene-1,2-diammonium dibromide three metal based dimeric surfactants containing cobalt, copper and zinc in the counterion were synthesized. The newly synthesized metallosurfactants were denoted [MBr4](dim) (M = Co, Cu, Zn). Constantly growing interest in the investigation and synthesis of novel dimeric surfactants is driven by their superior properties compared to conventional ones. By introducing metal ions into their structure unique compounds are created possessing magnetic, catalytic and redox properties in addition to their adsorption and aggregation capabilities. Du Noüy ring method was used to measure surface tension. Conductivity measurements were also used for critical micellar concentrations (cmcκ) determination. The size and zeta potential of micelles were measured by dynamic (DLS) and electrophoretic light scattering (ELS). It was found that the surface activity of dimeric metallosurfactants increases by replacing the conventional halogen Br- counterion with a complex one [MBr4]2-. In addition, the values of the critical micelle concentrations shifted towards lower values. DLS results showed that for all newly synthesised metallosurfactants transition from spherical to cylindrical micelles occur at relatively low concentrations. Differences in physicochemical properties within the newly synthesized series were not very pronounced and are more or less independent of the metal ion.

• Keywords: dimerne površinske aktivne tvari; površinska napetost; dinamičko raspršenje svjetlosti
• Keywords (english): dimeric surfactants; surface tension; dynamic light scattering
• Language: croatian
• URN:NBN: urn:nbn:hr:149:150553
• Study programme: Title: Applied Chemistry - Undergraduate study; specializations in: Environmental chemistry and green technologies, Advanced materials and technologies, Applied organic chemistry; Course: Advanced materials and technologies; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) primijenjene kemije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) primijenjene kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Embargoed access; Embargo expiration date: 2025-01-01
• Created on: 2023-09-14 10:59:07