Banca de QUALIFICAÇÃO: DANIELLA NATHALIA ROCHA DO NASCIMENTO

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : DANIELLA NATHALIA ROCHA DO NASCIMENTO
DATE: 19/12/2024
TIME: 08:00
LOCAL: PGTEC - sala 303
TITLE:

DEVELOPMENT OF CROSS-LINKED NANOFIBROUS MEMBRANES FOR CONTROLLED RELEASE OF ESSENTIAL OILS WITH ANTIMICROBIAL ACTIVITY

KEY WORDS:

Advanced textiles; Antimicrobials; Membranes; Nanofibers; Blow-spinning; Crosslinkng.

PAGES: 62
BIG AREA: Engenharias
AREA: Engenharia Química
SUBÁREA: Tecnologia Química
SPECIALTY: Têxteis
SUMMARY:

The development of multifunctional textile materials with nanometric structure and potential for high-technology applications, using polymers with lower cost and environmental impact, has shown promise for the most diverse areas of application. In this scenario, this research work aims to develop water-resistant, more sustainable and biocompatible nanofibrous membranes for the controlled release of natural essential oils with antimicrobial activity, derived from clove (Syzygium aromaticum) and thyme (Thymus vulgaris). To achieve this, polymeric polyethylene oxide membranes (PEO, 200,000 g/mol) were produced using the solution blow spinning method under different conditions, in addition to PEO crosslinking tests, in powder and nanofiber forms, with the use of the crosslinking agent tetraethyl orthosilicate (TEOS), to optimize the chemical and mechanical resistance of the membranes produced. The generated samples were characterized using polarized light optical microscopy (MOLP) and scanning electron microscopy (SEM-FEG), Fourier transform infrared spectroscopy (FTIR), Dynamic Light Scattering (DLS), X-ray diffractograms (XRD) and water solubility tests. The micrographs confirmed the production of membranes made up of fibers with diameters starting at 87 nm. The highest spinning efficiency was obtained when using 10% (m/m) PEO solutions in acetone:chloroform mixture in a 50:50 (m/m) ratio, with an injection flow of 0.5 mL/min at 90 °C.Such conditions allowed the obtaining of membranes with higher yields, fiber density and resistance, with the formation of layers. PEO crosslinking was proven through solubility and water contact angle tests, which demonstrated the increase in the hydrophobic character and water insolubility of the new material, as well as through X-ray diffractograms, thermogravimetric curves and absorption bands in the FTIR, which confirmed chemical and structural changes in the cross-linked PEO, providing an improvement in the material's thermal and chemical resistance. Preliminary analysis of the antimicrobial activity of essential oils allowed us to identify that the inhibitory zone against E. coli was considerable for one of the clove samples, selected for the production stage of nanofibers with antimicrobiological activity. PEO nanofibrous membranes cross-linked with TEOS showed promising properties for the generation of products with potential for several applications of high technological relevance, such as the manufacture of dressings, filters, disinfectant films, cosmetics and active packaging.

COMMITTEE MEMBERS:
Interna - 3336784 - HELOISE OLIVEIRA MEDEIROS DE ARAUJO MOURA
Interna - 2614285 - KESIA KARINA DE OLIVEIRA SOUTO SILVA
Externa ao Programa - 1805556 - LUCIENE DA SILVA SANTOS - nullInterna - 2614274 - MICHELLE CEQUEIRA FEITOR