Hidrofilicidade de filmes de amido/poli(butileno adipato co-tereftalato) (Pbat) adicionados de tween 80 e óleo de soja

Abstract

Resumo: A incorporação de amido ao polímero poli (butilenoadipatoco-tereftalato) (PBAT) através de blendas com alto teor de amido pode ser uma alternativa para obter embalagens biodegradáveis, minimizar custos e o uso de recursos não renováveis. No entanto, a adição de amido aumenta a permeabilidade ao vapor de água (PVA). A incorporação em filmes com amido de substâncias como óleos vegetais e surfactantes pode diminuir a hidrofilicidade, favorecendo as aplicações destes como embalagens. A hidrofilicidade dos filmes elaborados por blendas de amido/PBAT adicionados de óleo de soja (OS) e tween 80 (TW) foi avaliada considerando o efeito do OS e TW nas isotermas de sorção dos filmes, na PVA e nos coeficientes de difusão (D w ) e solubilidade (β) do vapor de água. Filmes com OS com ou sem TW apresentaram menor quantidade de água de sorção, sendo os filmes com menores quantidades de OS e sem TW menos hidrofílicos e menos permeáveis aos vapores de água. A adição de OS reduziu os valores de β e D w dos filmes de amido/PBAT. O efeito foi relacionado com o aumento das porções hidrofóbicas e da compatibilidade entre o amido e PBAT na presença de OS. Palavras-chave: Polímeros biodegradáveis, extrusão de sopro, blendas. Hydrophilicity of Starch and Poly(Butylene Adipate-Co-Terephthalate) (Pbat) Films Containing Tween 80 and Soybean OilAbstract: Incorporating starch into the poly(butylene adipate-co-terephthalate) (PBAT) polymer by means of blends with high starch contents is a possible option for producing biodegradable packaging using renewable resources and reducing costs. However, the addition of starch increases the water vapour permeability (WVP). The incorporation of substances as lipids and surfactants can reduce the hydrophilicity of films containing starch, favouring their use as packaging. The hydrophilicity of films produced from blends of starch/PBAT with added soybean oil (SO) and tween 80 (TW) was studied. The effects of these substances on the sorption isotherm, on the WVP and on the water vapour diffusion (D w ) and solubility (β) coefficients of the films were evaluated. The water sorption in films with SO, with or without TW, was low. The films with the lowest amount of SO and without TW were the least hydrophilic and less permeable to water vapour. Adding SO reduced the β and D w values of the starch/PBAT films. This effect was related to the increase in the hydrophobic portions and the compatibility between starch and PBAT in the presence of SO.

Nanocomposites films obtained from protein isolates of mechanically deboned chicken meat added with montmorillonite

“…Table 2 shows the thickness values obtained, with the amount of filmogenic solution placed on the plate and thickness. The thickness was determined as the arithmetic average of five random measurements of the area of the film, it was found that with an increase in solids, thickness increased too, same behavior found by Brandelero et al [12] who determined thicknesses of starch films in the same way and obtained a variation in thickness from 0.11 mm to 0.33 mm. On the other hand, Cortez-Vega et al [13] also determined the film thickness of croaker protein isolate by the mean of 10 thickness measurements.…”

The effect of gelatin amount on the properties of PLA/TPS/gelatin extruded sheets

“…"K" parameter is related to the sorption heat of the multilayer, and when K = 1, it is assumed that there is no interaction of the water vapor in the multilayer or no variation in the energy of sorption in multilayer, which occur in homogeneous solids [39] . In our study, this parameter was not affected by gelatin addition.…”

Microencapsulation of Roasted Coffee Oil by Complex Coacervation with Gelatin/Gum Arabic Enzymatically Crosslinked

“…The monolayer moisture content (mo) indicates the maximum amount of water that can be adsorbed in a single layer per gram of dry solid and it is a measure of number sorbing sites (MALI et al, 2005). The parameter K is related to the sorption heat of the multilayer, and when k = 1 it assumed that there is no interaction of the water vapor in the multilayer or no variation in the energy of sorption in multilayer, which occur in a homogeneous solids (BRANDELERO et al, 2013). Finally the parameter C is associated with the sorption heat of the monolayer, and the value obtained was lower than reported by Rocha-Selmi et al (2013).…”