M.Sc. Tezi Görüntüleme | |||||||||||||||||||||
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| Summary: THE INTERACTION OF NANOFIBRILLATED CELLULOSE BASED BIOPOLYMER MATRIXES WITH MODEL WOUND LIQUID Karadeniz Technical University The Graduate School of Natural and Applied Sciences Fiber and Paper Technology Graduate ProgramSupervisor: Prof.Dr. Sedat ONDARAL 2019, 57 Pages, 9 AppendixThe chitosan adsorption on films prepared by using nanofibrillated cellulose (NFC) with different content of aldehyde group was studied by means of Quartz Crystal Microbalance with Dissipation (QCM-D). Results showed that frequency change (∆f) was higher when the chitosan was sent to NFC film consisting more aldehyde group due to the higher adsorption of chitosan. The (∆f) and dissipation (∆D) factors completely changed during adsorption of chitosan pre-treated with acetic acid: ∆f increased and ∆D decreased, oppositely to un-treated chitosan. After acid treatment, molecular weight and crystallinity index of chitosan decreased addition to change in chemical structure. It was found that more phosphate buffered saline (PBS), as a model liquid for wound exudate, adsorbed to acid treated chitosan-NFC film having more aldehyde groups. The adsorption level of PBS decreased when PBS was injected to chitosan-NFC films because of crosslinking, preventing swelling of film. PBS adsorption on model films composed of gelatin and NFCs with different aldehyde and carboxyl content were studied by means of QCM-D. The results showed that frequency shift (Δf) increased with increasing gelatin content to 50% in films consisting NFC-1 and NFC-2. The dissipation shift and adsorption rate of PBS followed the same trend. Model films with NFC-1 having 1.22 mmol/g aldehyde and 0.6 mmol/g carboxyl groups adsorbed more PBS than those consisting of NFC-2 with 0.25 mmol/g aldehyde and 1.15 mmol/g carboxyl groups except for film composed of 50% gelatin. However, adsorption rate of PBS was found slower for NFC-1 containing film because breaking acetal and amidol bonds, due to the aldehyde groups in the network of cellulose and gelatin, needed more time. Keywords: Nanofibrillated cellulose, chitosan, aldehyde content, QCM-D, PBS | |||||||||||||||||||||