Diels-Alder thermoreversible polymer networks and their nanocomposites

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Star-shaped furoate-PCL: An effective compound for the development of graphite nanoplatelets-based films

The aim of this study was to improve the dispersibility of graphite nanoplatelets (GNP) in films based on poly(ε-caprolactone) (PCL). To this end, a star-shaped PCL with furoate-like end groups (PCL-Fur), potentially capable of interacting/reacting with the surface of the graphene layers through Diels-Alder reactions, was synthesized by enzymatic catalysis. PCL-Fur was applied for film development by blending it with a commercial high molecular weight PCL (PCL-L) and GNP. The reactivity of GNP with respect to furoate groups was demonstrated by studying the thermal behavior of the GNP/methyl 2-furoate system, while the dispersibility of graphite in the solution containing PCL-Fur was studied by UV–Vis measurements. GNP proved to be well dispersed and adhered to the polymer matrix in the PCL-L/PCL-Fur/GNP composite films prepared by casting, in contrast to the films based on the neat PCL-L. This fine GNP dispersion resulted in films characterized by high electrical conductivity

Prospettive e potenzialità della digitalizzazione del settore forestale in Italia

Information and Communication Technologies (ICT) play a key role for improving the implementation of sustainable forest management at local, regional, and global level. The ICT potential to easily exploit a wider and more up-to-date set of information on the economic, environmental, and so- cial value of forests is of relevant help for the daily work of technicians, land owners, and companies in boosting the efficiency and effectiveness of forest management. The concept of “Precision Forestry” (PF) was developed from the early 2000s, as a branch of precision farming or precision agriculture. PF includes the use of ICT, remote and proximal sensing technologies, and other devices to coordinate and control several processes on a spatial scale (“Precision”) for monitoring, planning, and managing forest resources (“Forestry”). The aim of this monography is to collect and describe some of the most important PF experiences applied or potential- ly useful for the Italian forestry sector. It may represent a reference guide for the stakeholders, such as forest owners, professional technicians, public administrators, and policy makers. The book includes eleven chapters reviewing the main tech- nological tools available in the Italian context and the most recent advances of ICT in forestry, also focusing on the strengths and weaknesses of their practical implementation. The opportunities and challenges of implementing PF meth- ods, practices and technologies are also discussed. In the first two chapters the precision forestry concept and its historical development are introduced. In the third chap- ter some basic elements of ICT, GIS, Global Navigation Satellite Systems (GNSS), remote/proximal sensing, and related technologies which are essential for a better compre- hension of PF applications are recalled. In chapter 4 recent advances in large scale forest inventories with a focus on mapping and on the spatial estimation of forest variables integrating field surveys and multisource re- motely sensed data are described. Current advancements in the acquisition of field information including Terrestrial La- ser Scanning (TLS), new digital dendrometers, tree-talkers, terrestrial cameras, and APP for portable devices such as smartphones or tablets for dendrometric tree measures and new citizen science applications to support quantitative and qualitative spatial estimation of forest variables over large areas (i.e., forest health, fuel types) are also presented. The chapter ends up with the description of some experiences in the implementation of Forest Information Systems in Italy to provide a simple open-access to such new generation of spatial forest information. In chapter 5 PF tools, instruments, and technologies to sup- port sustainable forest management are illustrated. APPs developed to acquire field plots data to simulate manage- ment operations, the application of photogrammetric tech- nologies from Unmanned Aerial Vehicles and TLS data for monitoring with high-spatial scale forest monitoring and for acquiring indicators at single tree level are presented. A de- tailed description of new user-friendly tools for forest roadplanning, design and construction, as well as forest opera- tion planning is also included. Precision forest tree farming (with particular reference to poplar cultivation), useful to promote and increase the prof- itability and sustainability of forest plantations within the Italian context is described in chapter 6. The innovation and enhancement within the supply chain of wood plantations (from planting to harvesting, including monitoring and identification of stress) by soil proximal sensing techniques, Early Warning Systems, and specific software are highlight- ed. Considering the even higher market demands, promoted by the large-scale planting programs for climate changes mit- igation and the demands for propagation material for en- vironmental recovery, innovative techniques and methods supported by ICT in the forest nursery sector are described in chapter 7. In chapter 8 available technologies related to precision har- vesting are analyzed and described taking into consideration the wood chain efficiency, by means of improved commu- nications between the owner/buyer and operators as well as among machineries used in forest operations, health and safety of forest operators, environmental impacts mitigation and recovery, and operators training. Advanced communi- cation systems and sensors for the exchange of data and information between machines, machine-equipments and/or machine-operators, teleoperations and automation are also described. Chapters 9 and 10 are related to wood products traceabil- ity, timber quality assessment as well as the technologies for the optimization of wood transformation processes. The concepts of wood product traceability and tracing, togeth- er with latest digital technologies for the identification and tracking of the logs (i.e., fingerprinting and RFID), are de- tailly reported. Chapter 11 is finally dedicated to the relationship between the EU policy framework and the digitalization process in both agricultural and forestry sectors. The book summarizes, under a proactive and homogeneous framework, PF methods, tools and technologies in relation with the digital transition of the Italian forestry sectors. The authors hope this book will be useful for improving the implementation of sustainable forest management practic- es at all levels in Italy, providing a comprehensive review useful for policy makers, technicians, forestry owners and students

Thermoreversible Cross-Linked Rubber Prepared via Melt Blending and Its Nanocomposites

A covalent adaptable network based on the thermoreversible cross-linking of an ethylene–propylene rubber through Diels–Alder (DA) reaction was prepared for the first time through melt blending as an environmental-friendly alternative to traditional synthesis in organic solvents. Functionalization of the rubber with furan groups was performed in a melt blender and subsequently mixed with different amounts of bismaleimide in a microextruder. Cross-linking was confirmed by FT-IR spectroscopy and insolubility at room temperature, while its thermoreversible character was confirmed by a solubility test at 110 °C and by remolding via hot-pressing. Mechanical and thermomechanical properties of the obtained rubbers showed potential to compete with conventionally cross-linked elastomers, with stiffness in the range 1–1.7 MPa and strain at break in the range 200–500%, while allowing recycling via a simple melt processing step. Nanocomposites based on the thermoreversible rubber were prepared with reduced graphene oxide (rGO), showing significantly increasing stiffness up to ca. 8 MPa, ∼2-fold increased strength, and thermal conductivity up to ∼0.5 W/(m K). Results in this paper may open for industrially viable and sustainable applications of thermoreversible elastomers

On a Biobased Epoxy Vitrimer from a Cardanol Derivative Prepared by a Simple Thiol–Epoxy “Click” Reaction

The development of this work lies in the relevant interest in epoxy resins, which, despite their wide use, do not meet the requirements for sustainable materials. Therefore, the proposed approach considers the need to develop environmentally friendly systems, in terms of both the starting material and the synthetic method applied as well as in terms of end-of-life. The above issues were taken into account by (i) using a monomer from renewable sources, (ii) promoting the formation of dynamic covalent bonds, allowing for material reprocessing, and (iii) evaluating the degradability of the material. Indeed, an epoxy derived from cardanol was used, which, for the first time, was applied in the development of a vitrimer system. The exploitation of a diboronic ester dithiol ([2,2'-(1,4-phenylene)-bis-[4-mercaptan-1,3,2-dioxaborolane], DBEDT) as a cross-linker allowed the cross-linking reaction to be carried out without the use of solvents and catalysts through a thiol-epoxy "click" mechanism. The dynamicity of the network was demonstrated by gel fraction experiments and rheological and DMA measurements. In particular, the formation of a vitrimer was highlighted, characterized by low relaxation times (around 4 s at 70 C-degrees) and an activation energy of ca. 48 kJ/mol. Moreover, the developed material, which is easily biodegradable in seawater, was found to show promising flame reaction behavior. Preliminary experiments demonstrated that, unlike an epoxy resin prepared from the same monomer and using a classical cross-linker, our boron-containing material exhibited no dripping under combustion conditions, a phenomenon that will allow this novel biobased system to be widely used

Arbuscular mycorrhizal fungi and plant growth-promoting pseudomonads increases anthocyanin concentration in strawberry fruits (Fragaria X ananassa var. Selva) in conditions of reduced fertilization.

Anthocyanins are a group of common phenolic compounds in plants. They are mainly detected in flowers and fruits, are believed to play different important roles such as in the attraction of animals and seed dispersal, and also in the increase of the antioxidant response in tissues directly or indirectly affected by biotic or abiotic stress factors. As a major group of secondary metabolites in plants commonly consumed as food, they are of importance in both the food industry and human nutrition. It is known that arbuscular mycorrhizal (AM) fungi can influence the plant secondary metabolic pathways such as the synthesis of essential oils in aromatic plants, of secondary metabolites in roots, and increase flavonoid concentration. Plant Growth-Promoting Bacteria (PGPB) are able to increase plant growth, improving plant nutrition and supporting plant development under natural or stressed conditions. Various studies confirmed that a number of bacterial species living on and inside the root system are beneficial for plant growth, yield and crop quality. In this work it is shown that inoculation with AM fungi and/or with selected and tested Pseudomonas strains, under conditions of reduced fertilization, increases anthocyanin concentration in the fruits of strawberry

Arbuscular mycorrhizal fungi and plant growth-promoting pseudomonads improve yield, quality and nutritional value of tomato: a field study

The aim of this work was to assess the effects of plant-beneficial microorganisms (two Pseudomonas strains and a mixed mycorrhizal inoculum, alone or in combination) on the quality of tomato fruits of plants grown in the field and subjected to reduced fertilization. Pseudomonas strain 19Fv1T was newly characterized during this study. The size and quality of the fruits (concentration of sugars, organic acids and vitamin C) were assessed. The microorganisms positively affected the flower and fruit production and the concentrations of sugars and vitamins in the tomato fruits. In particular, the most important effect induced by arbuscular mycorrhizal (AM) fungi was an improvement of citric acid concentration, while bacteria positively modulated sugar production and the sweetness of the tomatoes. The novelty of the present work is the application of soil microorganisms in the field, in a real industrial tomato farm. This approach provided direct information about the application of inocula, allowed the reduction of chemical inputs and positively influenced tomato quality