Degradability of expanded starch/PVA blends prepared using calcium carbonate as the expanding inhibitor

Biodegradation behavior and digestive properties of starch-based film for food packaging - a review

Non-degradable plastic places a serious burden on the environment, so consumers and researchers are working to develop biodegradable, safe, and sustainable food packaging materials. The starch-based film has become emerging material for food packaging. Not only does it shows excellent physicochemical properties, but also provides the desired degradation characteristics after use or the digestive properties after consumption, thus needing to comprehensively evaluate the quality of starch-based food packaging materials. This review summarizes the degradation behavior of the starch-based film in different degradation environments, and compares the suitability of degradation environments. Besides, the physicochemical properties of the composite or blend film during the degradation process were further discussed. The factors affecting the digestibility of starch-based edible film were reviewed and analyzed. Finally, the application and the future trend of the biodegradable starch-based film in the food packaging field were proposed. Future studies should combine and evaluate the physical properties and biodegradability of the composite/blend film, to develop food packaging materials with good characteristics and biodegradability.

Potential applications of polycarbohydrates, lignin, proteins, polyacids, and other renewable materials for the formulation of green elastomers

Renewable resources including polycarbohydrates, lignin, proteins, and polyacids are the intrinsically valuable class of materials that are naturally available in great quantities. Their utilization as green additives and reinforcing bio-fillers, in substitution of environmentally perilous petroleum-based fillers, for developing high-performance green rubber blends and composites is presently a highly tempting option. Blending of these renewable materials with elastomers is not straight-forward and research needs to exploit the high functionality of carbohydrates and other natural materials as proper physicochemical interactions are essential. Correlating and understanding the structural properties of lignin, carbohydrates, polyacids, and other biopolymers, before their incorporation in elastomers, is a potential approach towards the development of green elastomers for value-added applications. Promising properties i.e., biodegradability, biocompatibility, morphological characteristics, high mechanical properties, thermal stability, sustainability, and various other characteristics along with recent advancements in the development of green elastomers are reviewed in this paper. Structures, viability, interactions, properties, and use of most common natural polycarbohydrates (chitosan and starch), lignin, and proteins (collagen and gelatin) for elastomer modification are extensively reviewed. Challenges in commercialization, applications, and future perspectives of green elastomers are also discussed. Sustainability analysis of green elastomers is accomplished to elaborate their cost-effectiveness and environmental friendliness.

Starch/PCL composite nanofibers by co-axial electrospinning technique for biomedical applications

BACKGROUND

In this study, starch and polycaprolactone (PCL), composite nanofibers were fabricated by co-axial needle electrospinning technique. Processing parameters such as polymer concentration, flow rate and voltage had a marked influence on the composite fiber diameter. Fourier transform infrared spectroscopy, scanning electron microscopy (SEM), mechanical and physical properties (such as density, viscosity and electrical conductivity) of the composite fibres were evaluated. Moreover, a cell culture test was performed in order to determine their cytotoxicity for wound dressing application.

RESULTS

The effect of starch ratio in the solution on the properties and morphological structure of the fibers produced was presented. With lower starch concentration values, the fibers have greater ultimate tensile strength characteristic (mostly 4 and 5 wt%). According to SEM results, it can be figured out that the nanofibers fabricated have good spinnability and morphology. The mean diameter of the fibers is about 150 nm. According to results of cell culture study, the finding can be determined that the increase of starch in the fiber also increases the cell viability.

CONCLUSIONS

Composite nanofibers of starch/PCL have been prepared using a co-axial needle electrospinning technique. PCL was successfully encapsulated within starch. Fiber formation was observed for different ratio of starch. With several test, analysis and measurement performed, some important parameters such as quality and effectuality of each fiber obtained for wound dressing applications were discussed in detail.