The stochastic microstructure of recycled carbon fibre-reinforced composites poses significant challenges for process optimization and performance prediction, due to the disparity in scales between fibre diameter and fibre agglomerates size. This study establishes a comprehensive quantitative characterization framework to evaluate the microstructural evolution of recycled carbon fibre thermoplastic tapes processed under two distinct melt-compounding regimes with contrasting processing conditions. Utilizing a deep learning-based EfficientNet-B4 model and computer vision for robust fibre segmentation, we analysed the interplay between fibre morphology, orientation, and dispersion on large-field high-resolution micrographs. A novel quantitative approach revealed microstructural notions, hard to detect otherwise, and uncovered a critical trade-off governed by shear mixing history: while a shorter processing scenario preserved fibre length (>600μm), it resulted in a planar-random orientation state driven by the tumbling of large aggregates. Conversely, the longer processing scenario induced significant fibre fragmentation but facilitated a transition towards uniaxial alignment. To identify these changes in microstructure, novel homogenization factors (Cluster Prevalence Indicator (CPI) μ and Intra-Cluster Density Indicator (IDI) κ) and a Collective Similarity Index (CSI) were introduced. These metrics demonstrated that extended mixing transitions the material from a state dominated by volumetrically large, internally dense super-clusters to a locally dispersed microstructure, without altering the invariant global spatial periodicity (d^∗≈260μm). Furthermore, a comparative evaluation of statistical descriptors highlighted that while conventional topological metrics (e.g., Voronoi statistics) proved insensitive to processing variations, the proposed cluster-based metrics and eigenvalue-based orientation tensors successfully captured the structural nuances. This framework provides essential methods for tailoring the processing-structure relationships in recycled discontinuous fibre composites.

It is a global ambition to realize sustainable development goals (SDGs) by 2030 following the aspiring climate change and pollution alleviation, and thus, the notion of sustainable biorefinery has emerged as an indispensable asset for worldwide sustenance and economy. Animal derived materials are biopolymers that are produced in nature during the life cycles of animals and usually considered as versatile, biocompatible, non-toxic, stable, and cheap feedstock with a promising closed-loop life cycles in the industrial ecology of future materials. Such materials could produce a severe hazard to the environment and its occupants if not ditched appropriately. Conversely, animal derived wastes are complex molecules in which manifold structure and heterogeneous networks of inter- and intra-molecular clutches endure unresolved challenges to sustainable processing and purification of these valuable waste matrices into biomaterials with numerous applications. Utilizing ionic liquids (ILs), which are environmentally safe and recyclable alternatives to organic solvents, greatly facilitates the handling and processing of biopolymers obtained from animals. ILs have been used progressively for the use of biopolymers. Compared to customary techniques, ILs assisted processing of animal-based biopolymers is superior as ILs are noncorrosive, possess extremely low vapor pressure, exhibit high thermal solidity and superb dissolution capabilities under relatively moderate conditions. Currently, a broad spectrum of various techniques has been studied to further tune up the proficiency of ILs processing of animal derived biopolymers for sustainable product development. The primary aim of this review is to illustrate the latest advancements in technology wherein the ILs leverages as processing media for animal-based biopolymers for the manufacturing of a plethora of sustainable materials have been progressively recognized. In addition to examining how various ILs serve as solvents, reagents and/or (co)solvents, we also look at the larger process and system context in which the ILs are used. It is anticipated that the current review will infuse new thoughts and reconciliation in ILs-mediated processing of animal waste resources for a promising paradigm of sustainable biorefinery.

The field of engineering living materials (ELMs) seeks to engineer cells to form macroscopic materials with tailorable structures and properties. While the rheological properties of ELMs have been altered using synthetic biology methodology, the relationships connecting their sequence, structural, and rheological properties remain to be elucidated. Recently, our lab created centimeter-scale ELMs from Caulobacter crescentus that offer a platform to investigate this paradigm. Here, we explore how changing the elastin-like polypeptide (ELP) length within the protein matrix of this ELM impacts its microstructure and viscoelastic behavior. We demonstrate that shortening ELP produces fibers almost 2× thicker than other variants, resulting in a stiffer material at rest. Interestingly, the midlength ELP forms a complex structure with globules and multidirectional fibers with increased yield stress under flow conditions. Lengthening ELP creates thinner strands between cells with similar storage and loss moduli to those of the midlength ELP. This study begins to elucidate sequence-structure-property relationships in these ELMs and shows that they are complex with few parallels to other biocomposite models. Furthermore, it highlights that fine-tuning genetic sequences can create significant differences in rheological properties, uncovering new design principles of ELMs.

In embedded 3D printing, the supporting gel must provide the right rheological properties to keep the ink in place. It has previously been shown that a strong and stable 3D network can be formed by particle–particle interactions of hydrophobic fumed silicas suspended in a polar solvent. Here, the rheological properties of fumed silica gels in polyethylene glycol (PEG) are investigated. The recovery properties like storage modulus, yield stress, and recovery time of the gels made of fumed silica with alkyl-chains of different lengths are studied. A very fast recovery time (0.2 s) is achieved by increasing the length of the alkyl chains on the silica surface, leading to embedded printing results with high shape accuracy. However, with the engineered supporting gel, the formation of crevasses affects the shape of the filament. Previous approaches to reduce crevasse formation include the introduction of liquid fillers to avoid such distortions, which, however, prevents the reuse of the gels and leads to increasing waste production in embedded printing. Here, it is shown that by adjusting the rheology of the inks to fit the rheology of the supporting gel, high-shape accuracy prints with ideally round-shaped filaments can be achieved without the need for liquid fillers.

Organogelation is one of the most promising techniques to replace unhealthy saturated fats in foods, guaranteeing a similar texture but with the use of healthy unsaturated oils. Nevertheless, the number of food grade gelators is not high, and the discovery of new agents is still due to "serendipity". Among the different gelators investigated in the literature, fatty alcohols, i.e., aliphatic hydrocarbons with a hydroxyl group, represent an interesting alternative. Within this context, a mixture of long chain alcohols, commercially known as Policosanol, seems particularly promising. Policosanol can be extracted from natural sources such as sugarcane, beeswax, wheat germ, and rice bran. Policosanol is very effective in structuring edible oils even at a very low concentration (0.1%) and has positive health effects on the cardio-circulatory system and cholesterol levels. Therefore, structured vegetable oils can be obtained through the use of edible healthy gelators (i.e., Policosanol). The oleogels developed with Policosanol might be used as substitutes for traditional hard fats or as novel structured vegetable oil systems with controlled rheological properties. The rheological, microscopic, and sensory properties of fatty alcohol oleogels are discussed in this chapter, as well as their potential use for producing new foods and vehicles for the controlled release of nutraceutical compounds.

Rapid industrial development, vehicles, domestic activities and mishandling of garbage are the main sources of pollutants, which are destroying the atmosphere. There is a need to continuously monitor these pollutants for the safety of the environment and human beings. Conventional instruments for monitoring of toxic gases are expensive, bigger in size and time-consuming. Hybrid materials containing organic and inorganic components are considered potential candidates for diverse applications, including gas sensing. Gas sensors convert the information regarding the analyte into signals. Various polymeric/inorganic nanohybrids have been used for the sensing of toxic gases. Composites of different polymeric materials like polyaniline (PANI), poly (4-styrene sulfonate) (PSS), poly (3,4-ethylene dioxythiophene) (PEDOT), etc. with various metal/metal oxide nanoparticles have been reported as sensing materials for gas sensors because of their unique redox features, conductivity and facile operation at room temperature. Polymeric nanohybrids showed better performance because of the larger surface area of nanohybrids and the synergistic effect between polymeric and inorganic materials. This review article focuses on the recent developments of emerging polymeric/inorganic nanohybrids for sensing various toxic gases including ammonia, hydrogen, nitrogen dioxide, carbon oxides and liquefied petroleum gas. Advantages, disadvantages, operating conditions and prospects of hybrid composites have also been discussed.

Organic–inorganic nanohybrids-based polymer nanocomposites are made up of two different components, and these hybrids attained great attention over last decades due to their diversified framework and fascinating features. These nanohybrids possess synergistic characteristics of both organic and inorganic substances. Different synthetic routes are used to synthesize these materials with enhanced morphology, tunable features, and fine nanostructures. This chapter focuses on various synthetic routes for fabrication of organic–inorganic-based nanopolymeric composites. Synthetic strategies and protocols of different routes have been described in details. We have also discussed the advantages and limitations of all synthetic methods in details.

A large fraction of population is suffering from waterborne diseases due to the contaminated drinking water. Both anthropogenic and natural sources are responsible for water contamination. Revolution in industrial and agriculture sectors along with a huge increase in human population has brought more amount of wastes like heavy metals, pesticides and antibiotics. These toxins are very harmful for human health, therefore, it is necessary to sense their presence in environment. Conventional strategies face various problems in detection and quantification of these pollutants such as expensive equipment and requirement of high maintenance with limited portability. Recently, nanostructured devices have been developed to detect environmental pollutants. Polymeric nanocomposites have been found robust, cost effective, highly efficient and accurate for sensing various environmental pollutants and this is due to their porous framework, multi-functionalities, redox properties, great conductivity, catalytic features, facile operation at room temperature and large surface area. Synergistic effects between polymeric matrix and nanomaterials are responsible for improved sensing features and environmental adaptability. This review focuses on the recent advancement in polymeric nanocomposites for sensing heavy metals, pesticides and antibiotics. The advantages, disadvantages, operating conditions and future perspectives of polymeric nanocomposites for sensing toxic pollutants have also been discussed.

Glycerol pretreatment is a promising method for the environmentally-friendly transformation of lignocellulosic materials into sustainable cellulose-rich raw materials (i.e., biopolymer) to fabricate biocomposites. Here, a comparison of aqueous acidified glycerol (AAG) pretreatment of wheat straw (WS) with alkaline, hot water, and dilute acid pretreatments on the thermal and mechanical characteristics of their fabricated composite board is presented. A comparison of total energy expenditure during WS pretreatment with AAG and other solutions was estimated and a comparative influence of AAG processing on lignocellulosic constituents and thermal stability of WS fiber was studied. Results imply that AAG pretreatment was superior in generating cellulose- rich fiber (CRF) as compared to other pretreatments and enhanced the cellulose contents by 90% compared to raw WS fiber. Flexural strength of acidic (40.50 MPa) and hot water treated WS composite (38.71 MPa) was higher compared to the value of 33.57 MPa for untreated composite, but AAG-treated composites exhibited lower values of flexural strength (22.22 MPa) compared to untreated composite samples. Conversely, AAG pretreatment consumed about 56% lesser energy for each kg of WS processed as compared to other pretreatments. These findings recognize that glycerol pretreatment could be a clean and new pretreatment strategy to convert agricultural waste into high-quality CRF as a sustainable raw material source for engineered biocomposite panels.