Thermal, mechanical and permeation properties of gamma-irradiated multilayer food packaging films containing a buried layer of recycled low-density polyethylene

This paper describes polymer modification of bitumen with gamma-irradiated recycled (γ-LDPER) low-density polyethylene. The recycled low-density polyethylene (LDPER) was obtained from greenhouse films exposed to sunlight at least one year. The surface of theLDPERwas treated by gamma beam irradiation that provided formation of free radicals and some functional groups that may contribute to the creation of strong chemical bonds between polymer modifier and bitumen. Five different samples of bitumen/γ-LDPERcompositions with the modifier content, wt. %: 1, 3, 5, 7 and 9, were prepared. The effects of theγ-LDPERon original and aged bitumen were investigated by means of morphological, chemical, and physical testing program, including FTIR spectroscopy, conventional tests, rotational viscosity (RV), dynamic shear rheometer (DSR), and bending beam rheometer (BBR) tests. Superior performing asphalt pavements (Superpave) specifications were used to analyze mechanical test results as well as to determine the performance grades (PG) of the binders. Optimum usage of theγ-LDPERas modifier in bitumen were suggested after testing program. The results reveal the stiffening effect of theγ-LDPERon bitumen that provide enhanced temperature susceptibility and also promise better performance grades (PG) withγ-LDPERpolymer modification.

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Low-Density Polyethylene Films Carrying ferula asafoetida Extract for Active Food Packaging: Thermal, Mechanical, Optical, Barrier, and Antifungal Properties

Advances in Polymer Technology ◽

10.1155/2020/4098472 ◽

2020 ◽

Vol 2020 ◽

pp. 1-15

Author(s):

Razieh Niazmand ◽

Bibi Marzieh Razavizadeh ◽

Farzaneh Sabbagh

Keyword(s):

Polymer Matrix ◽

Food Packaging ◽

Barrier Properties ◽

Low Density Polyethylene ◽

Low Density ◽

Optical Barrier ◽

Leaf Extracts ◽

Polyethylene Films ◽

Active Food Packaging ◽

Ferula Asafoetida

The physical, thermal, mechanical, optical, microstructural, and barrier properties of low-density polyethylene films (LDPE) containing ferula asafoetida leaf and gum extracts were investigated. Results showed a reduction in elasticity and tensile strength with increasing extract concentration in the polymer matrix. The melting temperature and enthalpy increased with increasing concentration of extracts. The films containing extracts had lower L∗ and a∗ and higher b∗ indices. The films containing leaf extract had more barrier potential to UV than the gum extracts. The oxygen permeability in films containing 5% of leaf and gum extracts increased by 2.3 and 2.1 times, respectively. The morphology of the active films was similar to bubble swollen islands, which was more pronounced at higher concentrations of gum and leaf extracts. FTIR results confirmed some chemical interactions of ferula extracts with the polymer matrix. At the end of day 14th, the growth rate of Aspergillus niger and Saccharomyces cerevisea in the presence of the PE-Gum-5 reduced more than PE-Leaf-5 (3.7 and 2.4 logarithmic cycles, respectively) compared to the first day. Our findings showed that active LDPE films have desire thermo-mechanical and barrier properties for food packaging.

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Essential oils as additives in active starch-based food packaging films: A review

International Journal of Biological Macromolecules ◽

10.1016/j.ijbiomac.2021.05.170 ◽

2021 ◽

Author(s):

Thomás Corrêa Vianna ◽

Carolina Oliveira Marinho ◽

Luís Marangoni Júnior ◽

Salam Adnan Ibrahim ◽

Roniérik Pioli Vieira

Keyword(s):

Essential Oils ◽

Food Packaging ◽

Packaging Films ◽

Food Packaging Films

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