BIODEGRADABLE COMPOSITION OF POLYLACTIDE AND STARCH FOR ACTIVE FOOD PACKAGING
Rubrics: 1. CHEMISTRY
Authors:
1.
KNITU
2.
KNITU
3.
KNITU; KNRTU
Type:
Article
eLocation:
Status:
Published
Received:
07.08.2025
Accepted:
07.08.2025
Published:
07.08.2025
Language:
Russian
Keywords:
BIODEGRADABLE POLYMER COMPOSITION, POLYLACTIDE (PLA), STARCH, ACTIVE PACKAGING, CORONA ELECTRET, SURFACE POTENTIAL, IR SPECTROSCOPY
Abstract (English):
This paper describes the creation of compositions based on D-modified polylactide and corn starch, which acts as a dispersed filler, possessing both biodegradability and electric field properties (corona electrets). The IR spectrum of PLA reveals characteristic bands that reflect its chemical structure and functional groups: bands in the 3200-3600 cm⁻¹ range correspond to O-H stretching, those in the 2950-2870 cm⁻¹ range correspond to C-H asymmetric and symmetric stretching, pronounced bands in the 1750-1800 cm⁻¹ range relate to C=O stretching of carbonyl groups, while bands in the 1300-1450 cm⁻¹ range correspond to C-O-C and C-C stretching. Bands indicative of ether group stretching are found in the 1000-1300 cm⁻¹ range. Similar bands are observed in the IR spectrum of starch, as it contains analogous functional groups. However, starch exhibits stronger absorption bands around 3300-3500 cm⁻¹, which are mirrored in the spectra of the PLA-starch composites; specifically, higher starch content correlates with increased intensity in this region. Moreover, interactions between PLA and starch alter the IR spectra of their compositions. Experimental data reveal that the surface potential of polymer matrices composed of 2-6% starch exceeds that of pure PLA. This enhancement in the accumulation and retention of electric charge carriers in the polymers is attributed to the formation of new trapping sites within the filler structure and at the polymer matrix interface. Starch’s high polarizability contributes to local field effects, further facilitating charge retention, while its hygroscopic nature enables moisture retention, significantly influencing the electret characteristics of the polymer. The patterns observed in the surface potential of PLA and its starch composites over time align with typical behaviors seen in various polymer-based corona electrets. Two distinct phases are identified: an initial sharp decline in surface potential values followed by stabilization. These dynamics are controlled by the trapping of charge carriers in shallow, quickly depleting energy traps versus deeper traps that determine the electret’s longevity. The findings conclude that incorporating 2-6% starch into polylactic acid enhances its electret properties, suggesting the potential for developing active packaging solutions that extend the shelf life of food products.
This paper describes the creation of compositions based on D-modified polylactide and corn starch, which acts as a dispersed filler, possessing both biodegradability and electric field properties (corona electrets). The IR spectrum of PLA reveals characteristic bands that reflect its chemical structure and functional groups: bands in the 3200-3600 cm⁻¹ range correspond to O-H stretching, those in the 2950-2870 cm⁻¹ range correspond to C-H asymmetric and symmetric stretching, pronounced bands in the 1750-1800 cm⁻¹ range relate to C=O stretching of carbonyl groups, while bands in the 1300-1450 cm⁻¹ range correspond to C-O-C and C-C stretching. Bands indicative of ether group stretching are found in the 1000-1300 cm⁻¹ range. Similar bands are observed in the IR spectrum of starch, as it contains analogous functional groups. However, starch exhibits stronger absorption bands around 3300-3500 cm⁻¹, which are mirrored in the spectra of the PLA-starch composites; specifically, higher starch content correlates with increased intensity in this region. Moreover, interactions between PLA and starch alter the IR spectra of their compositions. Experimental data reveal that the surface potential of polymer matrices composed of 2-6% starch exceeds that of pure PLA. This enhancement in the accumulation and retention of electric charge carriers in the polymers is attributed to the formation of new trapping sites within the filler structure and at the polymer matrix interface. Starch’s high polarizability contributes to local field effects, further facilitating charge retention, while its hygroscopic nature enables moisture retention, significantly influencing the electret characteristics of the polymer. The patterns observed in the surface potential of PLA and its starch composites over time align with typical behaviors seen in various polymer-based corona electrets. Two distinct phases are identified: an initial sharp decline in surface potential values followed by stabilization. These dynamics are controlled by the trapping of charge carriers in shallow, quickly depleting energy traps versus deeper traps that determine the electret’s longevity. The findings conclude that incorporating 2-6% starch into polylactic acid enhances its electret properties, suggesting the potential for developing active packaging solutions that extend the shelf life of food products.
Keywords:
BIODEGRADABLE POLYMER COMPOSITION, POLYLACTIDE (PLA), STARCH, ACTIVE PACKAGING, CORONA ELECTRET, SURFACE POTENTIAL, IR SPECTROSCOPY
BIODEGRADABLE POLYMER COMPOSITION, POLYLACTIDE (PLA), STARCH, ACTIVE PACKAGING, CORONA ELECTRET, SURFACE POTENTIAL, IR SPECTROSCOPY
