Research of the Influence of the Ultrasonic Treatment on the Melts of the Polymeric Compositions for the Creation of Packaging Materials with Antimicrobial Properties and Biodegrability

Abstract

Ensuring the microbiological safety of food products is a problem of current interest. The use of antimicrobial packaging materials is a way of solving the problem. When developing packaging materials, it is advisable to use a modern approach based on the creation of biodegradable materials. The difficulty in the selection of the polymer compositions’ components lies in solving the dilemma of the joint introduction and processing of antimicrobial and biodegradable agents. The studies of the ultrasound treatment on the melts of polymer mixtures showed an increase in the dispersion process of the components of the mixture. In this regard, this work aimed to study the effect of the ultrasonic treatment on the melts of polymer compositions containing thermoplastic starch and birch bark extract (BBE). In the work, the properties of PE-based packaging materials with various BBE concentrations obtained with ultrasonic treatment of melts on a laboratory extruder were studied. Biodegradable polymer compositions containing thermoplastic starch and BBE, obtained with the use of the ultrasonic treatment during extrusion, were investigated. The methods for studying rheological, physic-mechanical, antimicrobial properties and sanitary chemical indicators of materials were used in the article. It was found that ultrasonic treatment increases the melt flow and contributes to the production of materials with the uniform distribution of additives. The BBE content from 1.0% and higher in the contents of the material provides antimicrobial properties. When studying the permeability of oxygen and water vapor of the polymer compositions based on PE and BBE, it was found that the introduction of a filler increases vapor permeability by about 8–12% compared with control samples. The optimal concentration of BBE in polyethylene compositions containing thermoplastic starch was determined. The extension of the shelf life of the food product during storage in the developed material was established.

Influence of the Ultrasonic Treatment on the Properties of Polybutylene Adipate Terephthalate, Modified by Antimicrobial Additive

“…At the BBE concentration of 1 wt % of the film became noticeably more yellow. For comparison, polyethylene (PE) granules and films are colorless and transparent [ 23 ]. The thickness of the obtained samples of PCM films is presented in Table 3 .…”

“…The antimicrobial properties of polymeric materials were evaluated in relation to microorganisms: Escherichia coli M 17 (E. coli) , Candida albicans ATCC 2091 (C. albicans) , Penicillium commune F-4486 (P. commune) by the disk diffusion method. The experimental technique is described in detail in [ 23 ]. Samples of polymeric materials in the form of disks ( d = 20 mm) were placed in Petri dishes with inoculated solid agar medium.…”

“…Inoculation of the samples was carried out by spraying the suspension of the mold spores on the surface of the film, preventing droplets from merging. The experimental technique is described in detail in [ 23 ]. The test duration was 14 days.…”

“…To assess the biodegradability of the obtained materials, the composting method was used, which is described in detail in the work [ 23 ] and ISO 14855. Samples of polymeric materials were placed in a container with vermicompost (TU 0391-11158096-2002) with the moisture content of at least 50% of its maximum moisture capacity.…”

“…Packaging based on PBAT with oregano essential oil was used for packaging fish fillets, which, in terms of microbiological indicators, increased the shelf life of packaged products by 10 days. Among the variety of natural antimicrobial additives with antibacterial, antiviral, anti-inflammatory, antimutagenic properties, as well as mold resistance, it seems possible to use birch bark extract (BBE) to modify packaging materials [ 23 , 24 ]. In the studies researches [ 25 , 26 ] of antibacterial properties and resistance of birch bark extract to mold are presented.…”