1,721,402 research outputs found
Polymeric Substrates Modification with Biobased Functional Compounds
Full text linkEditorial to the Special Issue "Polymeric Substrates Modification with Biobased Functional Compounds
An introduction to the circular economy
No full textThis book tries to debate on the significance of circular economy, underlying the necessity to change our way of producing, consuming, and traveling on a daily basis. The passage from a linear economy to a circular economy will help us to reduce the degradation of the environment for avoiding future disastrous consequences, such as depletion of biodiversity, scarcity of raw materials and drinking water, rising waters, etc. The circular economy, therefore, involves designing a product so that it can be recycled or its components reused. Reuse consists of introducing the product back into the economic circuit in its original condition; repair makes it possible to fix a broken good; and recovery consists of reusing its components. This is the significance of the so-called 3R strategy, illustrated in this book
Natural Polymers and Cosmeceuticals for a Healthy and Circular Life: The Examples of Chitin, Chitosan, and Lignin
Full text linkThe present review considers the design and introduction of new cosmeceuticals in the market, based on natural polymers and active molecules extracted from biomass, in a biomimetic strategy, starting with a consideration of the biochemical mechanisms, followed by natural precision biopolymer production. After introducing the contest of nanobiotechnology in relationship with its applicability for skin contact products and classifying the currently available sustainable polymers, some widely selected abundant biopolymers (chitin, chitosan, and lignin), showing specific functionalities (anti-microbial, anti-oxidant, anti-inflammatory, etc.), are described, especially considering the possibility to combine them in nanostructured tissues, powders, and coatings for producing new cosmeceuticals, but with potentialities in other sectors, such as biomedical, personal care, and packaging sectors. After observing the general increase in market wellness and beauty forecasts over the next few years, parallelisms between nano and macro scales have suggested that nanobiotechnology application expresses the necessity to follow a better way of producing, selecting, and consuming goods that will help to transform the actual linear economy in a circular economy, based on redesigning, reducing, recycling, and reusing
Skin-compatible biobased beauty masks prepared by extrusion
Full text linkIn the cosmetic sector, natural and sustainable products with a high compatibility with skin, thus conjugating wellness with a green-oriented consumerism, are required by the market. Poly(hydroxyalkanoate) (PHA)/starch blends represent a promising alternative to prepare flexible films as support for innovative beauty masks, wearable after wetting and releasing starch and other selected molecules. Nevertheless, preparing these films by extrusion is difficult due to the high viscosity of the polymer melt at the temperature suitable for processing starch. The preparation of blends including poly(butylene succinate-co-adipate) (PBSA) or poly(butylene adipate-co-terephthalate) (PBAT) was investigated as a strategy to better modulate melt viscosity in view of a possible industrial production of beauty mask films. The release properties of films in water, connected to their morphology, was also investigated by extraction trials, infrared spectroscopy and stereo and electron microscopy. Then, the biocompatibility with cells was assessed by considering both mesenchymal stromal cells and keratinocytes. All the results were discussed considering the morphology of the films. This study evidenced the possibility of modulating thanks to the selection of composition and the materials processing of the properties necessary for producing films with tailored properties and processability for beauty masks
Magmatic Gas Leakage at Mount Etna (Sicily, Italy): Relationships With the Volcano-Tectonic Structures, the Hydrological Pattern and the Eruptive Activity
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Modification of PLA-based films by grafting or coating
No full textRecently, the demand for the use of natural polymers in the cosmetic, biomedical, and sanitary sectors has been increasing. In order to meet specific functional properties of the products, usually, the incorporation of the active component is required. One of the main problems is enabling compatibility between hydrophobic and hydrophilic surfaces. Therefore, surface modification is necessary. Poly(lactide) (PLA) is a natural polymer that has attracted a lot ofattention in recent years. It is bio-based, can be produced from carbohydrate sources like corn, and it is biodegradable. The main goal of this work was the functionalization of PLA, inserting antiseptic and anti-inflammatory nanostructured systems based on chitin nanofibrils–nanolignin complexes ready to be used in the biomedical, cosmetics, and sanitary sectors. The specific challenge of this investigation was to increase the interaction between the hydrophobic PLA matrix with hydrophilic chitin–lignin nanoparticle complexes. First, chemical modification via the “grafting from” method using lactide oligomers was performed. Then, active coatings with modified and unmodified chitin–lignin nanoparticle complexes were prepared and applied on extruded PLA-based sheets. The chemical, thermal, and mechanical characterization of prepared samples was carried out and the obtained results were discussed
Terminal settling velocity measurements of volcanic ash during the 2002-2003 Etna eruption by an X-band microwave rain gauge disdrometer
No full texthis is the first report in the scientific literature of direct measurement of the terminal settling velocity of volcanic particles during an eruption. Field measurements using a continuous wave X-band disdrometer were carried out at Mt. Etna on 18 and 19 December 2002, when the explosive activity produced a 4 km high volcanic plume. These data allow the estimation of the intensity of the fallout and the measurement of the terminal settling velocities of the volcanic particles in real-time. The main results are: ( 1) the tested instrument detected coherent falling volcanic particles from 0.2 to 1 mm diameter; ( 2) measured terminal settling velocities were in agreement with both experimental and theoretical methods; ( 3) however, the measured velocities were clustered around few discrete values, rather than a range of velocities as would be expected if the particles were falling simultaneously and discretely. This new methodology has many new applications for local hazard mitigation and improved understanding of fallout processes
New insights on the Etna offshore reveal unknown morphological features related to the volcano eastern flank dynamics.
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