Because of the effort to preserve petroleum resources and promote the development of eco-friendly materials, bio-based polymers produced from sustainable resources have attracted great attention. Among them, polylactide (PLA) and natural rubber (NR) present prominent polymers with unique barrier and mechanical features. A series of samples with improved phase compatibility were obtained by blending PLA and NR using a double-rotor mixer. A plasticizing and enhancing effect on the polymers’ compatibility was achieved by using epoxidized soybean oil (ESO) as a natural plasticizer and compatibilizer. ESO compounding in the PLA-NR blends increased the mobility of the biopolymer’s molecular chains and improved the thermal stability of the novel material. The size of the NR domains embedded in the continuous PLA matrix decreased with the ESO content increment. The combination of thermal analysis and scanning electron microscopy enabled the authors to determine the features of potential packaging material and the optimal content of PLA-NR-ESO for the best mechanical properties.

The academic exploration and technology design of active packaging are coherently supplying innovative approaches for enhancing the quality and safety of food, as well as prolonging their shelf-life. With the object of comparison between two barrier materials, such as stable petrochemical polyurethane (PU), (BASF), and biodegradable natural poly(3-hydroxybutyrate) (PHB), (Biomer Co., Krailling, Germany), the study of antibacterial agent release has been performed. For the characterization of polymer surface morphology and crystallinity, the scanning electron microscopy (SEM), atomic force microscopy (AFM) and differential scanning calorimetry (DSC) were used respectively. The antimicrobial activity of chlorhexidine digluconate (CHD) has been estimated by the Bauer–Kirby Disk Diffusion Test. It was shown that the kinetic release profiles of CHD, as the active agent, in both polymers, significantly differed due to the superposition of diffusion and surface degradation in poly(3-hydroxybutyrate) (PHB). To emphasize the special transport phenomena in polymer packaging, the diffusivity modeling was performed and the CHD diffusion coefficients for the plane films of PU and PHB were further compared. The benefit of active biodegradable packaging on the base of PHB is discussed.

Poly (vinylidene fluoride) membranes were prepared by freeze-casting. The effects of PVDF concentration, and freezing temperature on the morphology, crystallization, and performance of prepared membranes were examined. Polymer concentration was varied from 10 to 25 wt%. The freezing temperature was varied from −5 to −25 °C. Dimethyl sulfoxide (DMSO) and distilled water were used as solvents and non-solvents, respectively. The first step of this study was devoted to estimating the optimal concentration of PVDF solution in DMSO. Membranes prepared at different ratios were characterized using physical and mechanical characteristics and porosity. The second step was to optimize the time required for the production of the membranes. In the third step, it was shown that the freezing temperature had a remarkable effect on the morphology of the membranes: as the temperature decreases, there is a transition from spherulite structures to interconnected pores. It was shown that the diversity in the pore pattern for PVDF affects remarkably the water permeability through the polymer membrane. During the monitoring of the spread of crystallized areas during the formation of the membrane, it was found that the crystallization of the solvent begins at localized points of the microscale, further crystallized areas spread radially or unevenly along the surface of the solution, forming contact borders, which can lead to changes in the properties of the membrane in its area.

This paper focuses on the study of novel blends based on poly(3-hydroxybutyrate) (PHB) and polymers with different hydrophilicity [polyethylene (PELD) and polyamide resin (PA548)]. Polymer blends were produced from five ratios of PHB/PELD in an effort to regulate the resistance to hydrolysis or (bio)degradation through the control of water permeability. The relation between the water transport and morphology (TEM data) shows the impact of polymer component ratio on the regulating water flux in hydrophobic matrix. To elucidate the role of hydrophilicity of the second component in the PHB blends, we studied the PHB/PA blends where PA is the polyamide resin composed of statistical copolymer of hexamethyleneadipinate and ε-caprolactam in ratio 1:1. The complex of techniques including DCS and Fourier Transform Infrared (FTIR)-imaging (on the scale of temperature) indicates an interaction between PHB and PA in the temperature ranges of crystallization and melting. The general approach based on Flory-Huggins equation is presented as a way to choose pairs of compatible or partly compatible polymers. Blending PHB with PA could be a simple and effective method to design new matrices for drug delivery, while the same procedure applied to PHB-PELD system with better resistance again, hydrolysis and lower cost than parental PHB could be used as novel bioerodible packaging materials.

Membrane technology is a crucial tool toward technological process intensification in chemical industry. In addition to its undeniable contribution to desalination and reuse of water, the spread of separation applications in industry could save great part of the energy. Beyond the contribution to the environmental and economic improvement of separation processes, the membrane manufacturing industry itself needs to minimize environmental and occupational risks, that means meet principles of "green" chemistry. Membrane manufacturing should be developed with the reduction or elimination of hazardous compounds. The chemical processes of membrane production are linked with the use of a wide range of solvents. A lot of organic solvents required for membrane production are classified as toxic or hazardous substances and their use is strictly limited by law. One of the promising environmentally friendly methods of production of membranes is the applying of "green" solvents. As an alternative technology, it is proposed to use the freeze method, in which non-toxic dimethyl sulfoxide (DMSO) is used as a solvent. This technology requires less energy consumption, which also allows implementing the principles of "green" chemistry. Microporous membranes based on poly(vinylidene fluoride) (PVDF) with a thickness of 100 to 250 mu m was carried out by freeze method. Dimethylsulfoxide (DMSO) was selected as the most environmentally friendly solvent for some fluoropolymers. Porosity, permeability, wettability, physical and mechanical characteristics for obtained membranes and their morphology were investigated. It has been found that the most optimal concentration of PVDF in the solution is 30 wt.%. In this case the best combination of technological and operational properties is provided. The efficiency of prepared membranes for microfiltration process was demonstrated by a suspension of the yeast Saccharomyces cerevisiae. Such technology in comparison with the existing ones, is devoid of some disadvantages like using of complex equipment and high operating temperature. Freeze method does not require high energy consumption and using of toxic solvents.