PLA composites formulated recycling residuals of the winery industry

Abstract

Particulate composites with polylactide (PLA) as a matrix and wastes deriving from the wine production have been formulated at different compositions. The microstructure and the mechanical properties of the composites, as well as the thermal stability and water uptake have been evaluated. The results showed that the wine waste residue does not compromise the thermal stability of the matrix while improves the impact strength and influences tensile properties. Specifically, tensile strength progressively decreases on addition of the winery waste, while the elastic modulus slightly increases. This behavior was attributed to the inhomogeneity of the filler particle size and morphology, which can partially induce a discontinuous interface at high filler loading and affect the water uptake. An increase in the value of the water contact angle is obtained below a 10% wt content and the mechanism of water uptake is not modified below the 20 wt% of filler. In any case, up to a content of 15 weight percent, winery wastes can be used in the plain matrix as an extender. Since simple and low cost operations are requested to obtain suitable fillers, an overall decrease in the material cost can be envisaged thus partially solving the drawbacks of PLA exploitation in the packaging industry, and leading to cost‐effective application. Moreover, the conversion of lignocellulosic wastes as filler in biocomposites would be in favor of waste reduction while adding value to the agro‐food chain. POLYM. COMPOS., 40:1378–1383, 2019. © 2018 Society of Plastics Engineers

On the Correlation of Lignocellulosic Filler Composition with the Performance Properties of Poly(ε-Caprolactone) Based Biocomposites

“…Group of peaks (e) in the range of 1370-1460 cm −1 is related with CH 2 and HOC in-plane bending vibrations, characteristic for carbohydrates, e.g. lignin [39,40], while signal (f) at 1235 cm −1 is associated with the stretching of C-O and C=O bonds [41]. The most intensive signal (g) was observed around 1010-1030 cm −1 , which is typical for FTIR analysis of lignocellulosic fillers [42] and can be associated with the stretching vibrations of C-O bonds [43].…”

Eco-Conversion of Two Winery Lignocellulosic Wastes into Fillers for Biocomposites: Vine Shoots and Wine Pomaces

“…Very few papers deal with the use of residues stemming from the wine-making process in the preparation of composites. The studies are mainly considering fossil and non-biodegradable polymers as matrices, i.e., polyolefins [ 22 , 23 , 24 , 25 ], epoxy resins [ 26 ], polystyrene ([ 27 ]) or poly(vinyl alcohol) [ 28 ], and to a lesser extent, biosourced and biodegradable matrices such as soy flour [ 28 ], and very recently poly(lactic acid) [ 29 ], poly(butylene succinate) [ 30 ] or poly(3-hydroxybutyrate- co -3-hydroxyvalerate) (PHBV) [ 31 ]. In particular, PHBV is a bacterial polyester presenting the advantage of being potentially prepared from agro-residues.…”

Enhancing the thermo‐oxidative stability of PLA through the use of hybrid organic–inorganic coatings

“…Previous studies carried out on polyolefin substrates (low-density polyethylene and cross-linked polyethylene) had underlined how hybrid coatings of different compositions could significantly hinder the thermo-oxidative degradation, prolonging the service life of the materials. 26,27 This effect is attributable at the very low permeability of these materials compared with that of common polymers. For example, oxygen transmission rate (OTR) of 45-mm thick LDPE films can be reduced more than three times when a 1-mm thick hybrid coating is applied.…”