Editorial - Polymer Analysis

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Biodegradable Foams

Biodegradable foams are currently gathering a wide interest from both academia and industry for several reasons. Specifically, resins from crude oil or natural gas are becoming less attractive as the price of the raw materials is increasing substantially. This is stimulating the researchers toward the design and preparation of new products, which may represent a valuable alternative. Also, within the current circular economy concept, further attempts toward the reduction of waste—and consequently, of its environmental impact—are being carried out, aiming at developing polymer resins from renewable sources suitable for producing reliable polymeric foams. In this context, recyclability and/or biodegradability have become very important in modern society, in order to limit the landfill confinement of synthetic plastic waste or products at the end of their life. This also considers the significant growth of the world population and consequently the reduced available space for plastic confinement. These findings justify the potential of these biodegradable polymers (and in particular of biodegradable foams) for different industrial applications. This chapter aims to elucidate the materials, processes, and applications of biodegradable foams. Finally, some perspectives about their possible future development are considered

Flame-Retardant systems based on chitosan and its derivatives: state of the art and perspectives.

During the last decade, the utilization of chitin, and in par0ticular its deacetylated form, i.e. chitosan, for flame retardant purposes, has represented quite a novel and interesting application, very far from the established uses of this bio-sourced material. In this context, chitosan is a carbon source that can be successfully exploited, often in combination with intumescent products, in order to provide different polymer systems (namely, bulky materials, fabrics and foams) with high flame retardant (FR) features. Besides, this specific use of chitosan in flame retardance is well suited to a green and sustainable approach. This review aims to summarize the recent advances concerning the utilization of chitosan as a key component in the design of efficient flame retardant systems for different polymeric materials

Hybrid organic/inorganic coatings through dual-cure processes: state of the art and perspectives

This paper reviews the current state of the art related to the synthesis and characterization of hybrid organic-inorganic (O/I) coatings obtained through the exploitation of dual-cure processes, which involve a photo-induced polymerization followed by a thermal treatment: this latter allows the occurrence of sol-gel reactions of suitable alkoxy precursors already embedded in the UV-curable system. After a brief introduction on hybrid organic-inorganic coatings, the first part of the review is focused on the design and feasibility issues provided by the dual-cure method, emphasizing the possibility of tuning the structure of the final hybrid network on the basis of the composition of the starting liquid mixture. Then, some recent examples of hybrid organic-inorganic networks are thoroughly described, showing their potential advances and the application fields they can be addressed to

Ontology-based services for agents interoperability

Tese de doutoramento. Engenharia Electrotécnica e de Computadores. 2006. Faculdade de Engenharia. Universidade do Port

How to reduce the flammability of plastics and textiles through surface treatments: recent advances

The high flammability of plastics, polymer composites, textiles, and foams represents a severe and stringent issue that significantly limits their use in all those sectors, where resistance to a flame or an irradiative heat flux is mandatory [...

Surface engineered fire protective coatings for fabrics through sol-gel and layer-by-layer methods: an overview

Fabric flammability is a surface-confined phenomenon: in fact, the fabric surface represents the most critical region, through which the mass and heat transfers, responsible for fuelling the flame, are controlled and exchanged with the surroundings. More specifically, the heat, the fabric surface is exposed to, is transferred to the bulk, from which volatile products of thermal degradation diffuse toward the surface and the gas phase, hence feeding the flame. As a consequence, the chemical and physical characteristics of the fabric surface considerably affect the ignition and combustion processes, as the surface influences the flux of combustible volatile products toward the gas phase. In this context, it is possible to significantly modify (and improve) the fire performance of textile materials by “simply” tailoring their surface: one of the currently most effective approaches exploits the deposition of tailored coatings, able to slow down the heat and mass transfer phenomena occurring during the fire stages. This paper reviews the current state of the art related to the design of inorganic, hybrid or organic flame retardant coatings, suitable for the fire protection of different fabric substrates (particularly referring to cotton, polyester and their blends). More specifically, the use of sol-gel and layer-by-layer (LbL) methods is thoroughly discussed; then, some recent examples of flame retardant coatings are presented, showing their potential advances and their current limitations

Biomacromolecules and Bio-Sourced Products for the Design of Flame Retarded Fabrics: Current State of the Art and Future Perspectives

The search for possible alternatives to traditional flame retardants (FRs) is pushing the academic and industrial communities towards the design of new products that exhibit low environmental impact and toxicity, notwithstanding high performances, when put in contact with a flame or exposed to an irradiative heat flux. In this context, in the last five to ten years, the suitability and eectiveness of some biomacromolecules and bio-sourced products with a specific chemical structure and composition as eective flame retardants for natural or synthetic textiles has been thoroughly explored at the lab-scale level. In particular, dierent proteins (such as whey proteins, caseins, and hydrophobins), nucleic acids and extracts from natural sources, even wastes and crops, have been selected and exploited for designing flame retardant finishing treatments for several fibers and fabrics. It was found that these biomacromolecules and bio-sourced products, which usually bear key elements (i.e., nitrogen, phosphorus, and sulphur) can be easily applied to textiles using standard impregnation/exhaustion methods or even the layer-by-layer technique; moreover, these “green” products are mostly responsible for the formation of a stable protective char (i.e., a carbonaceous residue), as a result of the exposure of the textile substrate to a heat flux or a flame. This review is aimed at summarizing the development and the recent progress concerning the utilization of biomacromolecules/bio-sourced products as eective flame retardants for dierent textile materials. Furthermore, the existing drawbacks and limitations of the proposed finishing approaches as well as some possible further advances will be considered

“Polymer Analysis” Section, in Journal Polymers

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Ontology-services agent to help in the structural and semantic heterogeneity

In the Virtual Enterprises (VE) environment, interactions between distributed heterogeneous computing entities representing different enterprises, people and resources, take place. These interactions, in order to be both syntactic and semantic compatible, need to follow appropriate standards (ontologies) well understood by all the participants. Even for each domain ontology, people may store their data in different structures and use different terms to represent the same concept. This paper focuses on an effort to create an Ontology-Services Agent to monitor the communication acts taking place in a Multi-agent System. The Ontology-Services Agent provides help in solving the Structural and Semantic Heterogeneity problem, enabling appropriate conversations and making it possible meaningful agreements between agents representing different enterprises and resources in a VE environment