Razvoj kompozita amonijevega fitata–hitozana–anorganskih oksidnih nanodelcev kot trajnostne ognjevarne apreture na svileni tkanini

Blagojevič, Maja (avtor), Tomšič, Brigita (mentor), Jerman, Ivan (komentor)

V magistrskem delu je predstavljen razvoj trajnostno zasnovane večfunkcionalne kompozitne ognjevarne in protimikrobne apreture za svileno tkanino na osnovi amonijevega fitata (AF), nanodelcev SiO2 in hitozana. Raziskava je bila izvedena v dveh sklopih. V prvem sklopu je bila določena optimalna koncentracija AF, ki zagotavlja ognjevarne lastnosti, primerljive s fitinsko kislino (FK), ob minimalnem vplivu na fizikalno-mehanske lastnosti svile. V drugem sklopu je bil sistem nadgrajen z vključitvijo nanodelcev SiO2 za povečanje termične stabilnosti zaščitnega sloja ter hitozana za zagotovitev protimikrobne aktivnosti. Za določitev optimalne koncentracije AF je bilo apreturno sredstvo naneseno po impregnirnem postopku v naraščajočih koncentracijah 1–20 % masnega deleža glede na celotno maso raztopine, primerjalno pa je bila v enakih koncentracijah uporabljena tudi FK. Za določitev vpliva apreture na morfološke in kemijske lastnosti svilene tkanine tako v primeru samostojnega nanosa AF in FK kot tudi v primeru kombinacije AF s SiO2 ter hitozanom so bile izvedene preiskave vrstične elektronske mikroskopije (SEM), energijske disperzijske spektroskopije (EDS) in infrardeče spektroskopije s Fourierjevo transformacijo (FT-IR). Ognjevarne lastnosti so bile preverjene z vertikalnim testom gorljivosti in z analizo določanja mejne vrednosti kisika (LOI). Določeni so bili upogibna togost, pretržna trdnost in raztezek ter zračna prepustnost apretiranih tekstilnih vzorcev. Na podlagi rezultatov in kriterija vrednotenja je bila kot optimalna koncentracija izbrana 10 % koncentracija AF, ki je izboljšala ognjevarnost v primerjavi s FK. Rezultati analize gorljivosti in termičnih lastnosti svile, apretirane z novorazvito večfunkcionalno apreturo, so potrdili izrazito izboljšano ognjevarno učinkovitost (LOI = 38,5). Prisotnost hitozana v večfunkcionalni kompozitni apreturi je popolnoma zavrla rast obeh modelnih bakterij na površini vzorca z vrednostjo protimikrobne aktivnosti 6,4 proti Escherichia coli in 5,7 proti Staphyloccocus aureus. Na podlagi standarda SIST EN ISO 17658 je bila preverjena tudi pralna obstojnost večfunkcionalne kompozitne apreture po petih ciklih pranja. Iz rezultatov je razvidno, da se je funkcionalnost apreture po pranju delno ohranila. Kljub temu, da se je po pranju povečala gorljivost vzorca, je bila le-ta kljub temu manjša od neapretirane svile. Pranje je vplivalo tudi na zmanjšanje protibakterijske učinkovitosti nanokompozitne apreture, ki pa je še vedno zagotavljala zadostno zaviranje rasti obeh modelnih bakterij. Analiza eksperimentalnih rezultatov je pokazala statistično pomembne povezave med sestavo apreture in merjenimi funkcionalnimi lastnostmi svile, kar potrjuje pomembnost vpliva posameznih komponent na končne lastnosti materiala.

• Jezik: Slovenski jezik
• Ključne besede: svilena tkanina, trajnostna večfunkcionalna ognjevarna apretura, amonijev fitat, silicijevi oksidni nanodelci, hitozan, protimikrobna zaščita
• Vrsta gradiva: Magistrsko delo/naloga
• Organizacija: NTF - Naravoslovnotehniška fakulteta
• Leto izida: 2026
• PID: 20.500.12556/RUL-182101
• Datum objave v RUL: 24.04.2026

Sekundarni jezik

• Jezik: Angleški jezik
• Naslov: Development of ammonium phytate–chitosan–inorganic oxide nanoparticle composite as sustainable flame retardant coating for silk fabrics

Izvleček

This master’s thesis presents the development of a sustainably designed multifunctional composite flame-retardant and antimicrobial finish for silk fabric, based on a system comprising ammonium phytate (AF), SiO2 nanoparticles and chitosan. The research was conducted in two phases. In the first phase, the optimal concentration of AF was determined to achieve flame-retardant performance comparable to phytic acid (PA), while minimising the impact on the physico-mechanical properties of silk. In the second phase, the system was enhanced by incorporating SiO2 nanoparticles to improve the thermal stability of the protective layer and chitosan to impart antimicrobial functionality. To determine the optimal concentration of AF, the finishing formulation was applied via a pad-dry process in increasing concentrations ranging from 1 to 20 % by weight relative to the total weight of the solution. PA was applied at identical concentrations for comparison. To determine the effect of the finish on the morphological and chemical properties of silk fabric, both in the case of independent application of AF and FK, and in the case of combinations of AF with SiO2 and chitosan, investigations were carried out using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and Fourier-transform infrared spectroscopy (FT-IR). Flame-retardant performance was assessed by the vertical flammability test and determination of the limiting oxygen index (LOI). In addition, bending rigidity, tensile strength, elongation at break, and air permeability were measured for selected concentrations. Based on the measured parameters and evaluation criteria, 10 % concentration of AF was identified as the optimal concentration, demonstrating superior flame-retardant performance compared to PA. The multifunctional finish exhibited significantly enhanced flame retardancy, as confirmed by an LOI value of 38.5. The presence of chitosan in the composite finish completely inhibited the growth of both model bacteria on the treated surface, achieving antimicrobial activity values of 6.4 against Escherichia coli and 5.7 against Staphylococcus aureus. Wash durability of the multifunctional composite finish was evaluated according to SIST EN ISO 17658 after five laundering cycles. The results show that the functionality of the finish was partially retained after washing. Although the flammability of the samples increased after washing, it was still lower than that of unfinished silk. Washing also reduced the antibacterial effectiveness of the nanocomposite finish, which still provided sufficient inhibition of the growth of both model bacteria. Statistical analysis revealed significant correlations between the finish composition and the measured functional properties of silk, confirming the importance of the influence of individual components on the final properties of the material.

• Ključne besede: silk fabric, sustainable multifunctional flame-retardant coating, ammonium phytate, silica nanoparticles, chitosan, antimicrobial protection