Primjena elektrokemijskih senzora pri kvantificiranju sastava i interakcija u formulacijama oplemenjivača rublja

doctoral thesis

• Title (english): The application of electrochemical sensors at quantification of composition and interactions in fabric softeners formulations
• Author: Maja Aničić
• Mentor: Mirela Samardžić (mentor)
• Committee member: Zoran Mandić (predsjednik povjerenstva)
• Committee member: Sandra Babić (član povjerenstva)
• Committee member: Tanja Pušić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2021-10-27, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry; Analytic Chemistry
• Universal decimal classification (UDC): 54 - Chemistry. Crystallography. Mineralogy ; 66 - Chemical technology. Chemical and related industries

Abstract

U svrhu optimizacije formulacije oplemenjivača rublja, ispitane su odzivne karakteristike dva elektrokemijska senzora selektivna na kationske površinski aktivne tvari (CS). Jedan senzor bio je ionsko selektivna elektroda (ISE) sa čvrstim kontaktom i polimernom tekućom membranom dok je drugi imao tekući kontakt (unutarnji elektrolit). Kao senzorski materijal u oba senzora upotrijebljene su višestjenčane ugljikove nanocjevčice (engl. multi-walled carbon nanotubes, MWCNT) funkcionalizirane sa cetilpiridinijevim (CP) kationom i sulfatnom grupom (MWCNT-OSO3-CP+). Na temelju boljih rezultata, za daljnja istraživanja, odabran je senzor sa čvrstim kontaktom i polimernom tekućom membranom. Potenciometrijske titracije i odzivne karakteristike ispitane su u odnosu na četiri CS tehničke čistoće i četiri CS analitičke čistoće. Najbolji odziv dobiven je za di-(masni karboksietil) hidroksietil metilamonijev metosulfat (MAS) (59.5 ± 1.1 mV/dekada aktiviteta u vodi i 57.5 ± 1.3 mV/dekada aktiviteta u CaCl2). Pri potenciometrijskim titracijama, najbolja istinitost (iskorištenje 99.8 %) dobivena je, također, koristeći MAS kao analit pa je MAS odabran kao CS za formulaciju oplemenjivača rublja. S obzirom na bolja primjenska svojstva oplemenjivača za rublje koji u svojoj formulaciji imaju silikon, kao dodaci korištena su četiri silikona pri različitim koncentracijama. Na temelju stabilnosti i viskoznosti sustava, za formulaciju oplemenjivača rublja odabran je dikvarterni polidimetilsiloksan (DPS) (w = 0.19 %). Utjecaj pH na potencijal nije bio značajan u rasponu između 3 i 8, a na istinitost potenciometrijskih titracija u rasponu između 3 i 7. Primjena CS procijenjena je mjerenjem potencijala strujanja kroz referentne tkanine u elektrokinetičkom analizatoru. Dobiveni elektrokinetički parametri indiciraju zaostajanje modelne otopine oplemenjivača (MOO) na bazi MAS (w = 9 %) s dodatkom silikona DPS (MOO 3) na pamučnim i poliesterskim tkaninama prilikom adsorpcije, ali i njegovu bolju stabilnost u usporedbi s drugim ispitanim MOO.

Abstract (english)

In order to optimize the fabric softeners formulations, the response characteristics of two electrochemical sensors for cationic surfactants (CS) were investigated. One of the sensors was an ion-selective electrode (ISE) with a solid contact and a polymeric liquid membrane while the other one had a liquid contact (internal electrolyte). The multi-walled carbon nanotubes (MWCNT) functionalized with a cetylpyridinium (CP) cation and sulfate group (MWCNT-OSO3-CP+) were used as a sensing material in both sensors. Based on the better results, a sensor with solid contact and polymeric liquid membrane was selected for further research. The potentiometric titrations and response measurements were performed using four CS of technical grade and four CS of analytical grade. The best slope was obtained for di-(tallow carboxyethyl) hydroxyethyl methylammonium methosulfate (MAS)
(59.5 ± 1.1 mV/decade of activity in water and 57.5 ± 1.3 mV/decade of activity in CaCl2). When using CS as analytes in potentiometric titrations, the best trueness (recovery 99.8 %) was obtained also using MAS, so it was chosen as CS for fabric softener formulation. Due to the better application properties of fabric softeners with silicone in their formulation, four silicones, at several concentration levels, were used as potential additives. Based on stability and viscosity of the system, silicone diquaternary polydimethylsiloxane (DPS) (w = 0.19 %) was chosen for fabric softener formulation. The pH influence on potential was not significant in the range between 3 and 8 and on recovery of potentiometric titrations in the range between 3 and 7. Application profile of CS was assessed through streaming potential measurements of reference fabrics in electrokinetic analyzer. Obtained electrokinetic parameters indicated on lag in adsorption of model fabric softener (MFS) based on MAS
(w = 9 %) with addition of silicone diquaternary polydimethylsiloxane (DPS) (MFS 3) on cotton and polyester fabrics but advantage in stability when compared with other MFS investigated.

• Keywords: senzori za površinski aktivne tvari; kationske površinski aktivne tvari; oplemenjivač rublja; silikoni; zeta potencijal
• Keywords (english): surfactant sensors; cationic surfactants; fabric softener; silicones; zeta potential
• Language: croatian
• URN:NBN: urn:nbn:hr:149:001899
• Promotion: 2021
• Study programme: Title: Engineering Chemistry - Doctoral Course; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, područje prirodnih znanosti, polje kemija (doktor/doktorica znanosti, područje prirodnih znanosti, polje kemija)
• Type of resource: Text
• Extent: 144 str. ; 30 cm
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2023-06-01 11:44:59