Síntese e caracterização de filmes à base de quitosana adicionados de reticulantes iônicos

Abstract

Chitosan is a fairly abundant polysaccharide derived from the N-deacetylation of chitin, often consideredawaste from the fishing industry. This polymer is highly targeted for its versatility of applications as in the biomedical, pharmaceutical, cosmetic and food industry. Their diverse applicability is result of their reactive groups (-OH, -CHONH2e –NH2) favoring interaction sand reactions with various other compoundsand materials. It presents diverse physical-chemical properties, such as: biocompatibility, atoxicity and biodegradability. However, chitosan presents low solubility in aqueous solutions with no added dilute acids. The development of the work aims to modify commercial chitosan in order to increase its hydrophilicity, making unnecessary the use of diluted acids in its dissolution. In the food industry is growing the concern about the environment, using more and more biodegradable packaging and milder processes that try to minimize residues. The importance of this work is the development of means to use apolymer obtained from residual biomass in the synthesis of films for food packaging, increasing its hydrophilicity and, consequently, eliminating the need to use diluted acids in its dissolution. The films obtained were added with ethylenediaminetetraacetic acid (EDTA) and sodium tripolyphosphate (TPP) as cross linkers. The films obtained in the work were characterized and had their properties studied, such as water vapor permeation and mechanical tests, such as elongation, Young's modulus and tensile strength. Through FTIR it was possible to study interaction sof the cross linking agent to the film matrix. The cross linking with EDTA and TPP showed modifications in their properties, such as decreasing water vapor permeation, elongation and increase of Young's modulus. Chitosan is easilyprotonatedin its amine group which facilitates interaction with negatively charged cross linkers. The films obtained may have their properties improved with the use of crosslinking agents and those adopted for the development of this work were ethylenediaminetetraacetic acid (EDTA) and sodium tripolyphosphate (TPP). After obtaining the cross linked films their properties were analyzed by water vapor permeation, elongation, Young's module and tensile strength.