Sinteza celuloznih kopolimera gama-zračenjem

master's thesis

• Title (english): Synthesis of cellulose copolymers by gamma-radiation
• Author: Matija Stojanović
• Mentor: Elvira Vidović (mentor)
• Committee member: Elvira Vidović (predsjednik povjerenstva)
• Committee member: Mirela Leskovac (član povjerenstva)
• Committee member: Katarina Marušić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2021-09-16, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering

Abstract

U ovom radu sintetiziran je kopolimer celuloze i poli(2-dimetilaminoetil-metakrilata) (DMAEMA). U svrhu priprave nanokompozita u kopolimer je dodano SiO2 nanopunilo. Polimerni filmovi izliveni su na podlogu odmah nakon sinteze, dok su nanokompoziti izliveni na podlogu nakon umješavanja SiO2. Dio uzoraka nanokompozita te dio uzoraka hidrogelova ozračeni su gama zračenjem od 100 kGy iz 60Co izvora. Omjer celuloze i DMAEMA-e u početnim reakcijskim smjesama bio je 1:1, 1:3 ili 1:5 mol/mol. N,N-dimetilacetamid/LiCl korišten je kao otapalo, a N,N-metilen-bis-akrilamid kao umreživalo. Mikrostruktura te svojstva pripravljenih hidrogelova i nanokompozita ispitani su optičkom mikroskopijom, pretražnom elektronskom mikroskopijom, mjerenjem kontaktnog kuta, FTIR spektroskopijom, termogravimetrijskom analizom te određivanjem antibakterijskih svojstava. Ozračivanjem uzoraka antibakterijska svojstva filmova su se znatno poboljšala. Svi uzorci pokazuju hidrofilnost površine. FTIR spektroskopija pokazala je povećan sadržaj
poli(2-dimetilaminoetil-metakrilata) u hidrogelu s povećanjem njegovog udjela u reakcijskoj smjesi. Pozitivan utjecaj zračenja na konačni sadržaj DMAEMA izraženiji je u slučaju njegovog većeg udjela u početnoj smjesi. Ugradnja SiO2 punila potvrđena je prisustvom vrpci karakterističnih za Si-O-Si veze. Mikroskopijama je utvrđeno da je punilo u nanokompozitima dobro dispergirano. Termogravimetrijskom analizom ispitivana je toplinska postojanost priređenih materijala.

Abstract (english)

In this work cellulose/poly(2-(dimethylamino)ethyl-methacrylate) (PDMAEMA) copolymers were synthesized. The nanofiller SiO2 was added in order to construct nanocomposites. The polymer films were casted directly after synthesis, while the nanocomposites were casted after mixing in the SiO2 filler. Before the casting, part of the samples was exposed to gamma radiation of 100 kGy from a 60Co source. Ratio of cellulose and DMAEMA of the initial reaction mixture was 1:1, 1:3 or 1:5 mol/mol. N,N-dimethylacetamide/LiCl was used as solvent and N,N-methylene-bis-acrylamide was used as crosslinker. Microstructure and properties of prepared samples were investigated by optical microscopy, scanning electron microscopy, contact angle measurements, FTIR spectroscopy, termogravimetric analyses and antibacterial properties. Gamma irradiation improved the antibacterial properties of hydrogels. All samples have hydrophilic surface. FTIR spectroscopy showed higher content of poly(2-(dimethylamino)ethyl-methacrylate) in hydrogel with higher ratio in reaction mixture. Positive influence of irradiation on definite content of DMAEMA is more pronounced with its higher ratio in initial mixture. Integration of SiO2 nanofiller is confirmed with the presence of bands that are caracteristic for Si-O-Si bonds. Microscopies showed that the nanofiller is well dispersed. Termogravimetric analyses was used to examine the thermal stability of prepared materials.

• Keywords: celuloza; DMAEMA; hidrogel; nanokompozit; gama zračenje
• Keywords (english): cellulose; DMAEMA; hydrogel; nanocomposite; gamma-radiation
• Language: croatian
• URN:NBN: urn:nbn:hr:149:114330
• Study programme: Title: Materials Science and Engineering - Graduate study; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka kemijskog inženjerstva (magistar/magistra inženjer/inženjerka kemijskog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2023-04-13 13:37:03