Abstract:Poly(L-lactic acid) (PLLA) films containing various concentrations of two natural antioxidants, α-tocopherol and resveratrol, were fabricated by a melt compounding and compression molding process. The influence of the antioxidants on the optical properties such as color and UV-visible light transmission was analyzed. The thermal, mechanical, rheological and physical properties of PLLA films with added antioxidants were assessed. PLLA films with added α-tocopherol and resveratrol showed a yellowish brown color … Show more
“…The packaging matrix chosen was poly(lactide) (PLA) because of its renewable character. The inclusion of natural antioxidants in PLA in the aim of developing an active material has already been suggested in literature [43][44][45]. Furthermore, some studies already exist pointing to the feasibility of inclusion of lignin into PLA [5,9,46,47].…”
is an open access repository that collects the work of Arts et Métiers ParisTech researchers and makes it freely available over the web where possible. Abstract Due to their polyphenolic structure lignins bear a number of interesting functional properties, such as antioxidant activity. Natural antioxidants are very much looked for in the aim of protection of light or oxygen sensitive goods and are being used in active packaging. Poly(lactide) (PLA)-lignin films were prepared by twin screw extrusion followed by thermo-compression using two different commercial sources of alkali lignins obtained from gramineous plants. A good dispersion of lignin in the matrix was observed. Mechanical properties of the compounded material were merely diminished and oxygen barrier properties slightly enhanced. The chromatographic study of the lignins revealed that the low molecular weight fraction of both lignins increased during the polymer processing. The migration of low molecular weight compounds in an ethanol/water solution simulating fatty foodstuff was performed and the antioxidant activity of the extract was analysed. It was found that the activity increases with increasing severity of the heat treatment because of the generation of free phenolic monomers during processing. These results open an interesting way for application of lignins as an active compound in packaging materials. Lignins do not impair the mechanical and barrier performance of the polymer and the plastics processing even allows for the generation of active substances.
“…The packaging matrix chosen was poly(lactide) (PLA) because of its renewable character. The inclusion of natural antioxidants in PLA in the aim of developing an active material has already been suggested in literature [43][44][45]. Furthermore, some studies already exist pointing to the feasibility of inclusion of lignin into PLA [5,9,46,47].…”
is an open access repository that collects the work of Arts et Métiers ParisTech researchers and makes it freely available over the web where possible. Abstract Due to their polyphenolic structure lignins bear a number of interesting functional properties, such as antioxidant activity. Natural antioxidants are very much looked for in the aim of protection of light or oxygen sensitive goods and are being used in active packaging. Poly(lactide) (PLA)-lignin films were prepared by twin screw extrusion followed by thermo-compression using two different commercial sources of alkali lignins obtained from gramineous plants. A good dispersion of lignin in the matrix was observed. Mechanical properties of the compounded material were merely diminished and oxygen barrier properties slightly enhanced. The chromatographic study of the lignins revealed that the low molecular weight fraction of both lignins increased during the polymer processing. The migration of low molecular weight compounds in an ethanol/water solution simulating fatty foodstuff was performed and the antioxidant activity of the extract was analysed. It was found that the activity increases with increasing severity of the heat treatment because of the generation of free phenolic monomers during processing. These results open an interesting way for application of lignins as an active compound in packaging materials. Lignins do not impair the mechanical and barrier performance of the polymer and the plastics processing even allows for the generation of active substances.
“…Furthermore, PLA modified with natural origin compounds has been proposed as active packaging [8,23,24]. In this way, Hwang et al, (2011) proposed PLA with added α-tocopherol and resveratrol as promising active functional membranes [8]. Jamshidian et al, (2012) studied PLA with ascorbyl palmitate although they reported high loss of antioxidant during polymer preparation and negatives results on PLA transparency [24].…”
Section: Introductionmentioning
confidence: 99%
“…So, additives are require for transparent PLA films to block light transmission [22]. Furthermore, PLA modified with natural origin compounds has been proposed as active packaging [8,23,24]. In this way, Hwang et al, (2011) proposed PLA with added α-tocopherol and resveratrol as promising active functional membranes [8].…”
Section: Introductionmentioning
confidence: 99%
“…In this sense, poly(lactic acid) (PLA) is one of the most attractive biopolymers with many short-term or disposable applications, such as disposable cutlery (plates, cups, lids and drinking straws), bags and film packaging [4,5]. PLA is also widely used in rigid and flexible food packaging applications [6] since it has been approved by the US Food and Drug Administration (FDA) as a food contact substance [7,8].. However, the use of PLA for food packaging is somewhat limited because of its poor ductility, thermal and oxygen barrier properties [3].…”
Polymers derived from renewable resources are now considered as promising alternatives to traditional petro-polymers as they mitigate current environmental concerns (raw renewable materials/biodegradability). d-limonene can be found in a variety of citrus, indeed is the main component of citrus oils and one of most important contributors to citrus flavor. The incorporation of limonene in PLA matrix was evaluated and quantified by Pyrolysis Gas Chromatography Mass Spectrometry (Py-GC/MS). Transparent films were obtained after the addition of the natural compound. Mechanical properties were evaluated by tensile tests. The effect of limonene on mechanical properties of PLA films was characterized by an increase in the elongation at break and a decrease in the elastic modulus. The fracture surface structure of films was evaluated by scanning electron microscopy (SEM), and homogeneous surfaces were observed in all cases. Barrier properties were reduced due to the increase of the chain mobility produced by the d-limonene.
“…The blending with the unsaponifiable compound !-tocopherol showed small gains in elongation at break, which extends already existing knowledge. It was already shown that the use of !-tocopherol as a natural antioxidant in PLA at small quantities (<4 wt%) induced a slightly T g decrease [74] but no increase in elongation at break [75]. Here, no elongation at break improvement upon was found using greater !-tocopherol amounts, despite solubility was assessed to be higher than other molecules (such as HPO and HCO, Table 4) and a T g decrease was observed (Table 3).…”
Section: Results and Discussion 31 Effects Of Free Fatty Acids Glymentioning
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.