Banca de QUALIFICAÇÃO: RAFAELA REIS FERREIRA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : RAFAELA REIS FERREIRA
DATA : 10/06/2021
HORA: 14:00
LOCAL: Google Meeting
TÍTULO:

BIODEGRADABLE FILMS CONTAINING NANOCELLULOSIS AND NANOCAPSULES OF ESSENTIAL OILS FOR ACTIVE PACKAGES

PÁGINAS: 112
GRANDE ÁREA: Outra
ÁREA: Multidisciplinar
RESUMO:

[14:08, 12/05/2021] Rafaela Reis: The large packaging market is an indicator of a society's consumption, and after its use, these have caused significant environmental impacts due to their accumulation in the form of solid urban waste. Biodegradable packaging is an alternative to replace those made by commodity plastics, as they have shorter decomposition times after use. Among biodegradable polymers, poly(butylene adipate-co-terephthalate) (PBAT), a highly flexible copolymer, is already used in the packaging industry. However, it has limitations in its mechanical, thermal, and antimicrobial properties. Thus, this dissertation aims to develop biodegradable polymeric films of PBAT / Nanocellulose / active agents [chitosan nanocapsules with essential oils (OE)] for possible use in active biodegradable packaging with antimicrobial activity. Cellulose nanostructures (NC) were obtained from eucalyptus residues after alkaline treatment, followed by mechanical grinding (1, 2, 3, and 4 h) and high-intensity ultrasound (10, 20, and 30 min). Chitosan nanocapsules (NQ) with essential oils (NQOE) of cinnamon cassia (NQC) and rosewood (NQPr) were prepared by ion gelation between chitosan (Qs) and sodium tripolyphosphate (TPP). The biodegradable films were produced with the incorporation of different concentrations of nanocellulose (NC) (2%, by mass) and NQOE (0, 1, 3, and 5%, by mass) by the casting method. The prepared NCs were characterized using structural, dimensional, thermal, and morphological properties, while the NQOE by morphological, thermal, physical-chemical, and biological properties, and finally, the active films analyzed for thermal, structural, and biological properties. The best condition for obtaining the NC samples was when the eucalyptus was ground for 2 h and subjected to 20 min of ultrasound. The use of ultrasound produced particulars with more homogeneous dimensions, with greater crystallinity, electrostatic and thermal stability. The NQOE showed monodisperse sizes, with the size ranging from 100 to 150 nm and spherical shape. These showed biological activity due to the synergistic antibacterial efficiency between chitosan and essential oil, that is, they showed inhibition against E. coli. and B. subtilis. Films containing 1 and 3% NQOE increased the crystallinity of the prepared films, while 5% by mass NQOE reduced this property, which may have facilitated the diffusion of OE in the films. The films showed potential for application in food packaging, being an alternative to the environmental problems related to conventional packaging.

MEMBROS DA BANCA:
Presidente - Interno ao Programa - 1760410 - JEVERSON TEODORO ARANTES JUNIOR
Membro Titular - Examinador(a) Interno ao Programa - 1676364 - JULIANA MARCHI
Membro Titular - Examinador(a) Externo à Instituição - LEONARDO GONDIM DE ANDRADE E SILVA
Membro Suplente - Examinador(a) Interno ao Programa - 1763443 - MARCIA APARECIDA DA SILVA SPINACE
Membro Suplente - Examinador(a) Interno ao Programa - 052.991.506-52 - JULIANA DA SILVA BERNARDES - UNICAMP
Membro Suplente - Examinador(a) Externo à Instituição - HELIO WIEBECK