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Asphalt self-healing by encapsulated rejuvenating agents is considered a revolutionary technology for the autonomic crack-healing of aged asphalt pavements. This paper aims to explore the use of Bio-Oil (BO) obtained from liquefied agricultural biomass waste as a bio-based encapsulated rejuvenating agent for self-healing of bituminous materials. Novel BO capsules were synthesized using two simple dripping methods through dropping funnel and syringe pump devices, where the BO agent was microencapsulated by external ionic gelation in a biopolymer matrix of sodium alginate. Size, surface aspect, and elemental composition of the BO capsules were characterized by optical and scanning electron microscopy and energy-dispersive X-ray spectroscopy. Thermal stability and chemical properties of BO capsules and their components were assessed through thermogravimetric analysis (TGA-DTG) and Fourier-Transform Infrared spectroscopy (FTIR-ATR). The mechanical behavior of the capsules was evaluated by compressive and low-load micro-indentation tests. The self-healing efficiency over time of BO as a rejuvenating agent in cracked bitumen samples was quantified by fluorescence microscopy. Main results showed that the BO capsules presented an adequate morphology for the asphalt self-healing application, with good thermal stability and physical-chemical properties. It was also proven that the BO can diffuse in the bitumen reducing the viscosity and consequently self-healing the open microcracks.

Hydrogels of TEMPO-oxidized nanocellulose (TO-CNF) were stabilized for dry-jet wet spinning using a shell of cellulose dissolved in 1,5-diazabicyclo[4.3.0]non-5-enium propionate ([DBNH][CO2Et]), a protic ionic liquid (PIL). Coagulation in an acidic water bath resulted in continuous core-shell filaments (CSF) that were tough and flexible: average dry (and wet) toughness of ~11 (2) MJ . m -3 and elongation of ~9 ( 14) %. CSF morphology, chemical composition, thermal stability, crystallinity, and bacterial activity were assessed using scanning electron microscopy with energy dispersive X-ray spectroscopy, liquid-state nuclear magnetic resonance, Fourier transform infrared spectroscopy, thermogravimetric analysis, pyrolysis gas chromatography-mass spectrometry, wide angle X-ray scattering and bacterial cell culturing, respectively. The coaxial wet spinning yields PIL-free systems carrying on the surface the cellulose II polymorph, which not only enhances the toughness of the filaments but facilities their functionalization.apply a strategy based on the principles of the circular economy. Bio-based materials and, in particular, cellulose nanomaterials (CNMs) have become excellent candidates in this regard, as they could partially replace materials based on non-renewable resources. Indeed, CNMs enable high-performance, green functional materials with a broad spectrum of applications, e.g., electronics, biomedical and tissue engineering scaffolds, coatings, food, textiles, and even in daily use goods [1][2][3][4][5][6][7][8] .Cellulose resources have the potential of becoming a platform to develop novel CNMs with high mechanical performance since nanocellulose, in its cellulose I crystalline phase, possess an elastic modulus of about 150 GPa and 18-50GPa in the longitudinal and transverse directions, respectively 9,10 . The regioselective C6 oxidation of nanocellulose fibers can be additionally catalyzed by the use of the 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) nitroxyl radical to produce hydrogels with high transparency 11 , an extensive degree of fibrillation 12 , and low cytotoxicity 13 . These TEMPO-oxidized cellulose nanofibers (TO-CNF) are suitable for applications in diverse fields such as packaging 3,4,[14][15][16] , textiles [17][18][19][20] , biosensing and bioelectronics 21,22 , fire retardancy 23 , wound dressing and cell delivery [24][25][26] , among others 3 . Despite its excellent mechanical properties, materials derived from nanocellulose and, in particular, TEMPO-oxidized nanocellulose, have several drawbacks inherent to its nature. For instance, these materials are mostly hydrophilic owing to the high concentration of hydroxyl and carboxylate groups; this causes mechanical instability of the formed materials under wet/humid conditions, and exhibit rather low aspect ratios compared to dissolved polymers. The limited aspect ratio makes it difficult to create oriented structures of cellulose nanofibrils by drawing 27,28 . Many attempts to overcome hydrophilicity challenges have been made through appr...

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