The research investigates the thermal behavior of mixed systems based on natural and artificial cellulose fibers used as precursors for carbon nonwoven materials. Flax and hemp fibers were employed as natural components; they were first chemically treated to remove impurities and enriched with alpha-cellulose. The structure, chemical composition, and mechanical properties of both natural and viscose fibers were studied. It was shown that fiber properties depend on the fiber production process history; natural fibers are characterized by a high content of impurities and exhibit high strength characteristics, whereas viscose fibers have greater deformation properties. The thermal behavior of blended compositions was investigated using TGA and DSC methods across a wide range of component ratios. Carbon yield values at 1000 °C were found to be lower for blended systems containing 10–40% by weight of bast fibers, with carbon yield increasing as the quantity of natural fibers increased. Thus, the composition of the cellulose composite affects carbon yield and thermal processes in the system. Using the Kissinger method, data were obtained on the value of the activation energy of thermal decomposition for various cellulose and composite systems. It was found that natural fiber systems have three-times higher activation energy than viscose fiber systems, indicating their greater thermal stability. Blends of natural and artificial fibers combine the benefits of both precursors, enabling the deliberate regulation of thermal behavior and carbon material yield. This approach opens up prospects for the creation of functional carbon materials used in various high-tech areas, including thermal insulation. 
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                            Innovative and Sustainable Composite Material for the Seismic and Energetic Upgrade of Historic Masonry Buildings
                        
                    
    
            Usually, energy and structural improvements for historic masonry buildings are addressed separately using distinct methods and protocols. This paper covers an integrated assessment of new composite materials to reduce the seismic vulnerability of historic masonry buildings while complying with sustainable conservation requirements, emissions’ reduction, and energy savings. Firstly, this study focused on selecting suitable thermal mortars that could serve as the base material for the innovative composite. Subsequently, the mechanical characteristics of these mortars were examined by subjecting them to compressive and three-point bending tests. Dynamic thermo-hygrometric simulations were conducted using commercially available software to check the energy performance of the composite material when used on walls of existing masonry buildings. The thermal mortar that exhibited the most favorable mechanical and thermal properties was subsequently reinforced with a basalt fabric. A composite sample was assembled and subjected to direct tensile testing to determine its stress–strain behavior. 
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                            - Award ID(s):
- 1916342
- PAR ID:
- 10538769
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Fibers
- Volume:
- 11
- Issue:
- 9
- ISSN:
- 2079-6439
- Page Range / eLocation ID:
- 76
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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