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Influence of pre-treatment in an alkaline medium on binding chitosan and 2,3-dihydroxy butandionic acid on cotton and polyester/cotton substrate
(Wydawnictwo Politechniki Łódzkiej, 2022) Grgac, Sandra Flinčec; Milčić, Valentina; Vrbić, Ana
The aim of this study was to investigate the binding success of chitosan to cotton and polyester/cotton materials via 2,3-dihydroxy butanedioic acid with prior leaching in 8% NaOH. Microwave energy was used in the preparation process, which due to its low energy potential, does not cause direct changes in the structure of the material but contributes to the speed of chemical reactions [1,3,4]. Samples were analyzed by spectroscopy with Fourier transform of infrared spectrum in the ATR technique. Determination of breaking force and elongation of the fabric was tested according to the HR EN ISO 13934-1:2013. The antimicrobial efficacy of all samples was tested according to the AATCC 147.
Natural dyeing of recycled cotton and polyester-cotton blended yarns with chitosan biomordant
(Wydawnictwo Politechniki Łódzkiej, 2022) Gisbert-Payá, Jaime; Uysal, Serkan; Capablanca, Lucía; Toprak-Cavdur, Tuba
Studies on recycling and natural dyeing have gained great importance for the textile sector, which creates the most pollution and causes significant problems. Chitosan and its forms with their versatile properties are of great importance for many industrial areas from textiles to medicine. In this study, the effects of different-molecular-weight-chitosans as biomordants on the natural dyeing of recycled cotton and cotton-polyester yarns were investigated. The colorimetry results showed that while chitosan increased the yellowness and chroma of the colors, it decreased their redness, it is caused the colors to shift towards orange-yellow region. This change could be mitigated by changing the conditions under which the dyeings were conducted. Medium molecular weight chitosan was more effective in these changes than the low ones. Although there were changes in the angles of the colors, it was observed that the color strengths increased with the rise of the chitosan concentration. Although higher color strengths were obtained from dyes without chitosan, the increase in color depths with the increase of chitosan concentration revealed that chitosan could be used as a mordant. The good washing fastness obtained were explained by the low color strengths or the strong binding of chitosan and dye to the fiber.
Preliminary studies on the preparation and properties of chitosan nonwovens modified with acid vapors
(Wydawnictwo Politechniki Łódzkiej, 2022) Sikorski, Dominik; Bauer, Marta; Frączyk, Justyna; Draczyński, Zbigniew
The aim of the study was to develop methods for modifying chitosan nonwovens in the gas phase (application of acid vapors). Organic and inorganic acids were used in the research. The time of treating chitosan nonwovens with acid vapors ranged from 10 to 120 min. The conducted research has shown that it is possible to modify chitosan nonwovens with the use of acid vapors (organic and inorganic). It was found that the action of acid vapors does not have a destructive effect on chitosan fibers (SEM tests), which means that the developed method can be applied to various forms of chitosan materials, while the modification is carried out on the finished form. Microbiological tests were used to investigate the activity and growth of the microorganisms, which were related to the acids in the modified nonwovens. Only materials modified with acetic acid and hydrochloric acid were found to have bacteriostatic properties against S. aureus and E. coli (gramnegative and gram-positive bacteria). It was also found that chitosan formate significantly reduced the number of colonies of S. aureus.
Sustainable and multifunctional natural fiber-based electric wire sheaths for smart textiles
(Wydawnictwo Politechniki Łódzkiej, 2022) Mehravani, Behnaz; Padrão, Jorge; Fernandes, Rui D.V.; Nicolau, Talita; Alves, Cátia; Ribeiro, Ana I.; Peixoto, Joaquim Jorge; Carvalho, Hélder; Zille, Andrea
Envisioning the development of sustainable products for improvement of daily life quality, a cable-like composite using natural fibers was developed to be potentially used in smart textiles. Natural fibers such as jute and hemp were used along with Bekinox®VN yarn. Bekinox®VN is a stainless steel conductive yarn often used in intelligent textiles within a wide range of applications such as antistatic, power and signal transfer, thermal conductivity or even as a heat resistant sewing yarn. Furthermore, applying a chitosan coating on the surface of the sheath will confer antibacterial properties, thus preventing the colonization and proliferation of bacteria, as well as natural fiber degradation. The chitosan coating was applied by a pad dry method. Tests were performed to evaluate the mechanical, electrical and antimicrobial properties. The results displayed that the best tensile strength was obtained for hemp fabric followed by cable composite. The antimicrobial properties were improved with the coating of chitosan and demonstrating excellent results against Gram-positive and Gram-negative bacteria. Although chitosan reduces the mechanical strength of the sheath, it confers antibacterial activity, which not only will preserve the fiber in the structure but will also protect human skin against possible crosscontaminations.
Właściwości przeciwutleniające chitozanu w kiełbasach bez dodatku azotanu(III)
(Polish Society of Food Technologists. Scientific Publisher., 2014) Bagnowska, Anna; Krala, Lucjan; Nowak, Agnieszka; Oracz, Joanna
Przesłanki teoretyczne wskazują, że dzięki dobrym właściwościom przeciwutleniającym chitozan może wchodzić w skład zestawu dodatków pozwalających na wyeliminowanie azotanu(III) z produkcji kiełbas. Aktywność przeciwutleniająca chitozanu zależy od sposobu jego pozyskania, budowy cząsteczkowej oraz od właściwości materiału biologicznego, do którego został dodany. Celem niniejszej pracy było określenie skuteczności przeciwutleniającej chitozanu o różnej masie cząsteczkowej, dodanego wraz z likopenem do wieprzowych kiełbas średniorozdrobnionych, przechowywanych w warunkach chłodniczych przez 35 dni. Właściwości przeciwutleniające chitozanu określono na podstawie wartości AV, zawartości MDA i kwasów tłuszczowych oraz parametrów barwy. Stwierdzono, że chitozan o masie cząsteczkowej 135·103 Da charakteryzował się najsilniejszym oddziaływaniem przeciwutleniającym. Wraz z likopenem spełniał on funkcję ochronną przed zmianami oksydacyjnymi w kiełbasach, w podobnym zakresie jak składniki tradycyjnej mieszanki peklującej. Natomiast chitozan o masie cząsteczkowej 68·103 Da wykazywał najsłabsze właściwości przeciwutleniające. Zmniejszenie zawartości kwasów PUFA w kiełbasie z dodatkiem chitozanu o masie cząsteczkowej 68·103 Da było około dwukrotnie większe (2,1 mg/g tłuszczu) niż w kiełbasie z dodatkiem chitozanu o masie cząsteczkowej 135·103 Da (1,1 mg/g tłuszczu). Stosunek kwasów tłuszczowych z szeregu n-6 do n-3 w badanych kiełbasach był trzykrotnie wyższy niż pożądany (12,9 - 16,3) i był charakterystyczny dla mięsa wieprzowego.
Włókna celulozowe z udziałem alginianu
(Wydawnictwo Politechniki Łódzkiej, 2022) Niekraszewicz, Barbara; Sochacka, Anita