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Alginate, a naturally sourced bio-polymer derived mainly from brown seaweed, has gained incredible attention due to its versatile properties and wide range of applications. This review outlines alginate regarding sources, extraction methods, classifications, and critical characteristics. The critical development of alginate, focusing on its application in 3D bioprinting in fields such as vascular tissue formation, bone printing, and cartilage printing, has been discussed. Recent trends regarding the application of alginate in different sectors, from cosmetic textiles to wastewater treatment, wound dressing, and preparation of intelligent materials, have also been probed. The techniques used, benefits, and limitations form the discussion of each application. In addition, future alginate perspectives are discussed by considering current research with potential innovations that can expand its utility. Particular attention is devoted to the promising role of alginate in these emerging technologies that hold promise for radical changes in many industries due to its biocompatibility, biodegradability, and unique physicochemical properties. This review seeks to lay down basic knowledge on alginate by synthesizing the state of the art and, in this way, brings out the gaps that might inspire further studies and development in this dynamic field.Article Highlights: The physicochemical and biological properties of alginate are described, along with the extraction process. It reports the application of alginates in 3D bioprinting, cosmetic textiles, smart materials with techniques and limitations involved. Future perspectives of alginate are mentioned. [ABSTRACT FROM AUTHOR]

Introduction Consumer demand for healthy food free of chemical preservatives and environmental concerns with plastic packaging environments are analyzed, which can be replaced by aquatic environments that can be contaminated, for the development of bio-based packaging materials. Natural polymers have the ability to be biodegradable due to the presence of oxygen or nitrogen atoms in their main polymer chain compared to the dominant carbon-carbon bonds in fossil-based polymers. Among the various biopolymers used to prepare multilayer films, polysaccharides are considered as the main components of the film due to their abundance and non-toxicity. These films generally have good mechanical strength, moderate physical properties, and most importantly, are edible and easily degradable. However, they are very brittle and hydrophilic, and these properties are undesirable in food packaging applications. Among polysaccharides, agar, commercially extracted from seaweed, is one of the most common and widely studied base materials. Agar is insoluble in cold water, but soluble in water at 90-100°C. When making an agar film, the solution and casting surface must be kept above the agarose gel setting temperature to avoid premature gelation. Compared to other biopolymers, agar is more stable at low pH and high temperature. This thermoplastic and biocompatible polysaccharide creates films with high mechanical strength, transparency and moderate barrier properties to carbon dioxide and oxygen, and most importantly, it is edible and easily biodegradable. Mixing agar with other polymers such as polyvinyl alcohol (PVA) and polyethylene improves the mechanical, thermal and biodegradability properties of bio composites. The main goal of this study is to make biofilms for use in packaging industries with agar polymer extracted from macroalgae species Acanthophora sp. Agar was extracted by sodium hydroxide/heating method and the film was prepared in combination with industrial polymer PVA and glycerol. Materials and Methods To make biofilms based on agar polymer, firstly, optimization of agar polymer extraction from macroalgae species Acanthophora sp. was done by sodium hydroxide/heating method, and in the next step, total phenolic compounds and the amount of soluble protein in extracted agar were measured. In the next step, glycerol with 30% by weight was used as a softener and PVA polymer with a weight ratio of 25% to the dry weight of agar powder was used to make bio composite by solvent casting method, in order to strengthen the mechanical and physical properties of bio composites. Characterization tests of the prepared composites included: XRD, FTIR and Tensile test. Laboratory tests include; The percentage of solubility in water and degree of swelling for all bio-composites were evaluated to determine the optimal physical properties of bio-films. Results and Discussion: he results showed that; 15% extraction efficiency was obtained for sodium hydroxide/heating pretreatment method. The results of measuring the amount of total phenolic compounds in agar solution extracted by sodium hydroxide/heating method showed that the number of phenolic compounds in agar solution was 0.077 ± 0.004 in terms of mg of gallic acid/g of agar. The results of measuring the amount of protein in extracted agar determined by Bradford method showed that the agar solution contains 0.040 ± 0.019 mg/ml of protein. A decrease in the swelling rate and an increase in the water solubility of the agar bio composite occurred with the addition of glycerol and PVA polymer. The results of the tensile test showed that the addition of glycerol, a small hydrophilic molecule, to the agar bio composite leads to a decrease in the elastic modulus and an increase in flexibility. Adding PVA to agar/glycerol biofilm caused a decrease in the amount of elastic modulus and percentage of flexibility, which is the main factor of this phenomenon, the low values of elastic modulus and flexibility of PVA. Finally, the results confirm the use of these coatings for packing fruits and vegetables in tropical regions by increasing their shelf life for at least 5 days at 25°C.

Coir is a lignocellulosic natural fiber derived from the coconut's husk, an abundantly found fruit or nut worldwide. This fiber has some unique characteristics, such as its resistance to seawater, microbial attack, high impact, etc. But its low thermal conductivity or high thermal insulating property makes it suitable for being used as insulators in civil engineering sites. On the other hand, the sustainability of a material depends heavily on its environmental impact of the material. For making sustainable materials like biocomposite, there are no options other than using polymers derived from natural renewable sources. Polylactic acid(PLA) is an example of those types of material. And these materials are often being reinforced by fibers like coir for various reasons including improving mechanical properties, reducing the cost of the material, and improving the material's sustainability. Many coir-reinforced sustainable biopolymer composites have already been produced in many pieces of research, which will be discussed in this paper, along with the chemical and physical structure of coir fiber. In addition, this paper will try to focus on the insulating properties of coir and coir-reinforced composites while will also compare some properties of the composites with some commonly used materials based on different parameters to show the suitability of using the coir fiber in heat-insulating applications and to produce sustainable biocomposite materials.

This examination explains the utilization of bio-polymer powder for clayey soil enhancement. The article concentrates around examining the strength attitude of the clayey soils built up with homogenous bio-polymer. Carboxy methyl cellulose was determined as bio-polymer material to build up the normal soft clayey soil. The biopolymer has been added to the soil with two separated rates (0.5 and 3%) by total weight of soil. Different tests were carried out to consider the impact of utilizing this polymer as a balancing out specialist on the geotechnical properties of soil. It was estimated that as the bio-polymer content expands in the soil, the specific gravity decreases, while the optimum water content (OMC) is expanded. The results showed different effects on Atterberg’s limits; by increasing the liquid limit(L.L) and plasticity index(P.I) while the plastic limit decrease. The tests additionally mirrored a huge improvement in the unconfined compressive strength (UCS) of the treated soils. With the increment in biopolymer content, the consolidation index (Compression index Cc and recompression index Cr) decrease.

Biomimetic is the name of the approach that seeks sustainable solutions to the problems, taking the perfect functioning of nature for millions of years. The interest shown in biomimetic surfaces, inspired by multi-scale structures found in many plants and animals, is increasing day by day. Especially the unique wettability properties of the lotus leaf and rose petal. In this study, inspired by the structures of lotus leaf and rose petal, using the soft casting method with dental bio-polymer materials, structures with pillar dimensions of micron (µm) and millimeter (mm) were produced. These structures are replicated from two commercial products with different pillar lengths and different pillar shapes, mushroom and conical needle tips. Surface topographies of the replicated final products were analyzed by optical and stereo microscopes. Contact angles were tested to examine the wettability properties of the surfaces. According to the microscope results obtained, the demolding process, which is the riskiest step of the replication process, was successfully passed thanks to soft casting. Contact angle analysis showed that different pillar lengths and different pillar shapes changed the wettability properties of the replicated final product. The replicated mushroom-shaped micron-scale pillar structures exhibited a rose-petal effect and hydrophobic properties (approximately 1000) with only a single-scale configuration, while conical needle-shaped pillars of millimeter (mm) scale did not show any specific wetabilitty property.

The schematic representation is showing the bending behavior of the SAA and CLC-SAA. The strip for pH 1 (acidic) and pH 14 (alkaline) on the left side. On the right side bending behavior of SAA and CLC-SAA for pH 7. [Display omitted] • Integrated sodium alginate hydrogel with cholesteric liquid crystal for pH sensing. • Extensively investigated the hydrogen bonding mechanism employed for pH sensing. • Demonstrates exceptionally quick bending responses in the millisecond range. • Highly adaptable for applications in soft robotics, the food industry, and various other fields. The present work developed a novel type of soft actuator capable of pH sensing, named CLC-SAA (Cholesteric Liquid Crystal-Infused Sodium Alginate Actuator). This actuator is created by combining sodium alginate hydrogel with cholesteric liquid crystal via an evaporation method. Our study validates the actuation mechanism by observing shifts in the vibrational stretching of carboxylic group bonds through FTIR spectroscopic investigations. Leveraging the weak acidic nature of carboxylic acid in sodium alginate hydrogel, this actuator offers distinct advantages. The CLC-SAA exhibits remarkably rapid bending responses, with fast responses observed of the order of 4 sec to 0.4 sec and bending angles as low as 3° to as high as 18°. This responsiveness is consistent across a wide range of pH values, making it highly adaptable and valuable for applications in medical, chemical, and bio-robotics fields. Such actuation holds significant promise for various applications due to its adaptability and wide-ranging capabilities. [ABSTRACT FROM AUTHOR]

Impacts of Marine Plastic Debris (MPD) on marine ecosystems are among the most critical environmental concerns of the past three decades. Virgin plastic is often cheaper to manufacture than recycled plastics, increasing rates of plastic released into the environment and thereby impacting ecosystem health and functioning. Along with other environmental effects, MPD can serve as a vector for marine hitchhikers, facilitating unwanted organisms’ transport and subsequent spread. Consequently, there is a growing demand for more eco-friendly replacements of conventional plastic polymers, ideally with fit-for-purpose properties and a well-understood life cycle. We enriched polybutylene succinate (PBS) with three different concentrations of oyster shell to investigate the dynamics of biofouling formation over 18 weeks at the Nelson Marina, Aotearoa/New Zealand. Our study focused on oyster shell concentration as a determinant of fouling assemblages over time. While generally considered as a waste in the aquaculture sector, we used oyster shells as a variable of interest to investigate their potential for both, environmental and economic benefits. Using bacterial 16S and eukaryotic 18S rRNA gene metabarcoding, our results revealed that following immersion in seawater, time played a more critical role than substrate type in driving biofouling community structures over the study period. In total, 33 putative non-indigenous species (NIS) and 41 bacterial families with putative plastic-degrading capability were detected on the different substrates. Our analysis of NIS recruitment revealed a lower contribution of NIS on shell-enriched substrates than unadulterated polymers samples. In contrast, the different concentrations of oyster shells did not affect the specific recruitment of bacterial degraders. Taken together, our results suggest that bio-based polymers and composites with increased potential for biodegradability, recyclability, and aptitude for the selective recruitment of marine invertebrates might offer a sustainable alternative to conventional polymers, assisting to mitigate the numerous impacts associated with MPD.

The present study deals with the incorporation of different ratios of alkali-treated coir fibres (CF) and pineapple leaf fibres (PALF) in polylactic acid (PLA) hybrid composites. Developed hybrid composites are characterized in terms of mechanical, morphological, thermal and physical properties. Mechanical characterization revealed that alkali-treated C3P7 hybrid composites (CF:PALF = 3:7) showed highest tensile strength (30.29 MPa) and young’s modulus (5.16 GPa) among all hybrids composites, whereas C1P1 (CF:PALF = 1:1) showed highest impact properties. Scanning electron microscopy (SEM) justified the consequence of alkali treatment on fibre-matrix adhesion. Thermal analysis revealed that C1P1 and C7P3 (CF:PALF = 7:3) having a higher thermal stability and char content due to the higher content of lignin in CF. Remarkably, the coefficient of thermal expansion (CTE) of treated hybrid composites displayed lesser values than untreated hybrid composites. The physical tests revealed that C3P7 showed highest water absorption (WA) and thickness swelling (TS) though after treatment the WA and TS values get reduced. Overall results indicated that treated CF/PALF/PLA hybrid composites possess enhanced mechanical, thermal and physical properties with lowered CTE over untreated CF/PALF/PLA hybrid composites. The success of these findings results sustainable and degradable hybrid composites for different outdoor and food packaging-based applications.

This study investigates the tensile and compressive failure behavior of a single-lap joint of green composites obtained by resistance welding. The green composites composed of poly (lactic)acid (PLA) and bamboo fiber were fabricated in a hot compression by the film-stacking method. The different heating elements namely polypyrrole (conductive polymer), carbon fiber (CF) fabric, and stainless steel (SS) mesh were used to perform the resistance welding of nonconductive green composites. The heating time (30, 60, and 90 s) and the percentage of overlapping area covered by the heating element (35, 65, and 100%) were the other two welding parameters considered for experimental investigation. The effect of welding parameters on tensile and compressive failure loads was experimentally investigated through a full-factorial experimental design. The load vs. displacement and failure behavior of the welded specimen under different conditions was extensively investigated. The statistical analysis of the experimental data was performed to find the relative significance of the welding parameters. The type of heating element was found to be the most significant parameter as it has maximum statistical contribution in both tensile and compressive failure loads. The tensile and compressive failure loads were improved by 31% and 63% when CF fabric was used as a heating element as compared to the SS mesh heating element. Similarly, failure loads obtained by using CF fabric were improved by 187% (tensile) and 323% (compressive) when compared one-on-one with polypyrrole heating element.

The meat industry produces a lot of waste, which contains large amounts of the organics and nutrients. Animal by-products have potential for biomaterial extraction. The use of bio-material, which can be obtained from plant sources, microorganisms, agricultural, and animal waste are nowadays favored because of their compatible, cost-effective, and low-risk for removal of pollutants, compared to chemical and physical methods. In this study, a biopolymer from meat by-product extracted by methanol-chloroform and characterized by FTIR, GC–MS, HPLC, and SDS-PAGE analyzes. The extracted biomaterial was useful in water desalination by calcium carbonate precipitation and heavy metals removal, which was confirmed by FTIR and ICP analyzes. The extracted biomaterial also has antibacterial properties against Pseudomonas aeruginosa and Escherichia coli without toxicity to human blood cells, which can make it useful in industries such as its application in fish ponds. [ABSTRACT FROM AUTHOR]

The extensive discomfort in the expulsion of toxic pollutants even at mild concentrations has demanded the need for prompt methods for the evacuation of dyes and heavy metals. The effective method for depuration of dye from the effluent is by sorption. Chitosan is a bio‐polymer which is gaining an increasing interest as one of the sorbents. It was obtained from the crab shells by undergoing several chemical processes and used as an adsorbent for dye, metal removal and also for pharmaceutical purposes. Cross linking it with other co polymers will increase the capacity of adsorption to a maximum level. Fish scales are considered to be a major waste in the food industry and since it takes a long time for decomposing it is considered to be one of the pollutants. Hence it is utilised by converting it into activated carbon by preliminary treatment and into a muffle furnace. The obtained activated carbon is combined with chitosan by using a cross linker and utilised for adsorption mechanism. To analyse the effect of chitosan cross linked with activated carbon obtained from fish scales in adsorption of dye Reactive Blue 9 (RB9) to evaluate the adsorption studies, kinetics, mass transfer studies, thermodynamics of the bio adsorbent. [ABSTRACT FROM AUTHOR]

To increase the safety of our environments, the selection of proper building block for bio-polymer synthesis becomes vital. This research focused on determining the degree of unsaturation and reactivity of unsaturated milk bush (Thevetia peruviana) oil (TPO). The oil was extracted from Thevetia peruviana seed by Soxhlet extraction method and was further purified. Structural elucidation and characterization of purified TPO was carried out using Proton NMR spectrophotometer, Fourier transform infrared (FTIR) spectrophotometer and Gas chromatography mass spectrometer. The results revealed that the non-edible oil has a triglyceride structure, with 3.16 carbon - carbon double bonds per triglyceride which can be used as starting material to synthesized bio-polymer. [ABSTRACT FROM AUTHOR]

Microbially induced carbonate precipitation (MICP) by using ureolytic bacteria is a novel and environmentally friendly way to treat the un-cemented sand. It was implemented successfully in number of geotechnical applications. Use of organic additives to improve the MICP process is a novel and interesting approach. In this research, effect of the cationic biopolymer poly-l-lysine on the MICP process was investigated by using ureolytic bacteria Pararhodobacter sp. Urea hydrolysis by the bacteria in the presence of CaCl2 was conducted with the addition of the polymer under different conditions. Morphology of the precipitate of CaCO3 after oven dried was analyzed by using the scanning electron microscope. Bell-shaped curve was obtained for the variation between the amount of the precipitate with the increase of the amount of the poly-l-lysine. Poly-Llysine gives higher amount of precipitate than conventional MICP process and morphology of the crystals changed drastically from well-developed rhombohedral crystals to ellipsoidal shaped aggregates. [ABSTRACT FROM AUTHOR]

The remarkable ability of polymeric additives to reduce the level of frictional drag significantly in turbulent flow, even under extremely low dilutions, is known as turbulent drag-reduction behavior. Several bio-polymers have been assessed as promising drag-reducing agents for the potential replacement of high molecular weight synthetic polymers to improve safety and ameliorate environmental concerns. This article reviews the recent advances regarding the impact of several bio-polymer additives on turbulent drag reduction in either pipe or rotating disk flow systems, and their potential applications in the petroleum, biomedical, and agricultural industries. [ABSTRACT FROM AUTHOR]

The aim of this study was to formulate drug-loaded bio-lipstrips using novel bioexcipients isolated from the fruit pulp of Litchi chinesis (biomaterial L) and to explore the potentiality of lip skin as a novel translabial drug delivery system. The biomaterial, prepared by a simplified economical process and purified by hot dialysis, was subjected to various physicochemical evaluations along with spectral analysis including UV, FT-IR, Mass and 1H NMR. The lipstrip formulated with the novel bioexcipients was screened for its functional properties, including filmability using a film-casting method, and bio/muco-adhesitivity using a shear-stress method, the Park and Robinson method and a rotating cylinder method. Rosiglitazone-loaded bio-lipstrips were formulated by using biomaterial L as a strip former and dextrose as a flexicizer. The formulated strips were subjected to various evaluations, including thickness, folding endurance, in-vitro release and in-vivo release. The release of rosiglitazone maleate was maintained over 24 h, which was confirmed in in-vitro and in-vivo release experiments. Our results reveal that this biopolymer possesses promising stripability as well as bio-adhesitivity. The formulated bio-lipstrips are feasible for delivering rosiglitazone maleate by translabial administration.

Novel uses of Makapuno mutant coconut were explored. The focus was on the endosperm, which is rich in galactomannan as compared with that of the normal coconut. Galactomannan, also referred to as gum, is a non-starch polysaccharide that can vary in physicochemical properties depending on the plant source. The galactomannans available in the market are imported and sourced mostly from temperate leguminous plants. An inexpensive, large-scale method of isolating galactomannan from waste Makapuno liquid endosperm was developed. The powder produced could be classified into different grades according to purity, fineness, color and whether it is food-grade or not. It has the functional properties of a thickener, binder, extender, gelling agent, emulsifier and stabilizer. To showcase the use of Makapuno galactomannan as a plant-based biopolymer and a hydrocolloid material, several formulations were tried and tested to come up with products such as biodegradable or edible film, jelly, hand and body lotion, and even electrophoresis gel. However, they have to be further improved in terms of quality, shelf life and safety for commercialization to be considered. Other prospective applications of Makapuno galactomannan are discussed.

A novel adsorbent poly (methyl methacrylate)-grafted alginate/Fe3O4 nanocomposite was synthesized by oxidative-free radical-graft copolymerization reaction. The nanocomposite was characterized using FT-IR, X-ray diffraction, SEM, TEM, TGA and DSC techniques. The potential of nanocomposite material was explored towards the adsorption of Pb(II) and Cu(II) from aqueous media under varying operating conditions such as pH, concentration of metal ions, contact time, adsorbent dose and temperature. The optimum pH recorded for metal ions adsorption was 5. The experimental data were tested using Langmuir, Freundlich, Sips and Temkin models, and the data were best followed by Freundlich model at 50˚C. The maximum sorption capacity was found to be 62.5 mg g−1 for Pb(II) and 35.71 mg g−1 for Cu(II), respectively. The concentration and temperature dependent rate constants were evaluated using various kinetic models, and the data were best followed by pseudo-second-order kinetic model. The thermodynamic parameters such as enthalpy, entropy and free energy of activation were calculated to explain the nature of adsorption process. [ABSTRACT FROM AUTHOR]

Appropriate surface wettability of membranes and materials are of an extreme importance for targeting separation of mixtures/emulsions such as oil from water or conversely water from oil. The development of super-wettable membranes and materials surfaces have shown remarkable potential for recovering water from oil-water emulsion while offering maximum resistance to fouling. The availability of clean and potable water has been regarded as an important global challenge for coming human generations. Oil and gas industry is continuously producing immense quantities of waste stream regarded as produced water which contains oil dispersed in water along with other several components. Treating such immense quantities of oily wastewater is of utmost need for recovering precious water for possible reuse or safe disposal. Various technologies have been developed for targeting the separation of oil-water emulsions or mixtures to harness useful potable water and oil as products. Membrane-based separations or use of porous materials such as mesh have been explored in literature for separation of oil-water mixtures/emulsions. Given the unique features of special hydrophilicity, ease of tunability, control of molecular weight, abundant availability, and potential for commercial scale up, chitosan has been extensively used for modifying membranes/meshes or preparing composites with other materials for oil-water separations. This review has described in detail the synthesis, methods of modification and application of chitosan-based super-wettable membranes/meshes and porous materials for oil-water separation. The special wettability features including super-hydrophobicity/superoleophilicity, super-oleophobicity/super-hydrophilicity and super-hydrophilicity/underwater super-oleophobicity of various chitosan-based membranes and materials have been discussed in detail in the review. The strategies for enhancing or developing special wettability for target specific applications have also been discussed. Finally, the challenges, their respective importance have been identified along with a discussion on possible solutions to these challenges. [Display omitted] • First review article on superwettable surfaces based on natural polymer "chitosan" • Strategies for developing special wettability surfaces for target specific applications • Chitosan based surfaces with selective wettability for separation of oil and water • Advancements of chitosan based porous membranes for oil-water emulsion separation [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to formulate drug-loaded bio-lipstrips using novel bioexcipients isolated from the fruit pulp of Litchi chinesis (biomaterial L) and to explore the potentiality of lip skin as a novel translabial drug delivery system. The biomaterial, prepared by a simplified economical process and purified by hot dialysis, was subjected to various physicochemical evaluations along with spectral analysis including UV, FT-IR, Mass and 1H NMR. The lipstrip formulated with the novel bioexcipients was screened for its functional properties, including filmability using a film-casting method, and bio/muco-adhesitivity using a shear-stress method, the Park and Robinson method and a rotating cylinder method. Rosiglitazone-loaded bio-lipstrips were formulated by using biomaterial L as a strip former and dextrose as a flexicizer. The formulated strips were subjected to various evaluations, including thickness, folding endurance, in-vitro release and in-vivo release. The release of rosiglitazone maleate was maintained over 24h, which was confirmed in in-vitro and in-vivo release experiments. Our results reveal that this biopolymer possesses promising stripability as well as bio-adhesitivity. The formulated bio-lipstrips are feasible for delivering rosiglitazone maleate by translabial administration. [Copyright &y& Elsevier]

Hydroxyapatite composites are the main biomaterials used for metal implant coatings. Their in vitro study is very important. That is why their behavior was monitored in simulated body fluid (SBF), which is a solution with ion concentrations and pH value similar to those of human blood plasma. Silica, chitosan and gelatin-doped hydroxyapatite-based biomaterials were studied in SBF; the samples were characterized pre-, during and post-SBF immersion using infra-red, scanning and transmission electron spectroscopy and X-ray diffraction methods. The solubility of materials in SBF was determined, and the variation of Ca and phosphorus concentration was also recorded during SBF experiments. The results were compared and their in vitro biological activity was determined. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

In this study, we simulate the electrophoretic motion of a bio-polymer through a synthetic nanopore in the presence of an external bias voltage by considering the hydrodynamic interactions between the polymer and the fluid explicitly. The motion of the polymer is simulated by 3D Langevin dynamics technique by modeling the polymer as a worm-like-chain, while the hydrodynamic interactions are incorporated by the lattice Boltzmann equation. We report the simulation results for three different lengths of the nanopore. The translocation time increases with the pore length even though the electrophoretic force on the polymer is the same irrespective of the pore length. This is attributed to the fact that the translocation velocity of each bead inside the nanopore decreases with the pore length due to the increased fluid resistance force caused by the increase in the straightened portion of the polymer. We confirmed this using a theoretical formula. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates relationships between the emission of volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs) from five representative Mediterranean plant species and bio-polymers extracted from the leaves. The experimental results showed that there are differences in bio-polymer composition according to the species. Erica arborea is the fuel that contains most of holocellulose (cellulose and hemicellulose) and Pinus laricio is the fuels containing most of lignin. The plant samples were burned using an epiradiator. Automated Thermal Desorption–Gas Chromatography–Flame Ionization Detector (ATD–GC–FID) and Automated Thermal Desorption-Gas Chromatography/Mass Spectrometry (ATD–GC/MS) analysis identified 71 compounds, the compounds emitted from ligno-cellulosic fuel are VOCs and SVOCs. These emissions represented from 1164.5±163.4 to 1437.9±244.0μgg−1 dw of combustible fuel. There are not significant differences in the total emissions according to the species, but differences in the proportions of lignin, cellulose, hemicellulose and extractives led to quantitative variations in the class compounds present in the smoke. Partial Redundancy Analysis (RDA) highlighted presence of strong relationships between the emissions of some subfamilies of compounds and the proportions of the various bio-polymers. [ABSTRACT FROM AUTHOR]

The need for durable concrete in marine environments such as areas prone to tidal flooding is important due to its ability to deteriorate the structures. This led to the design of a durable and strong Polymer-Modified Concrete (PMC) using natural or bio-polymer modified concrete. However, the use of biopolymer-modified concrete is very limited. Therefore, this research developed a bio-polymer modified concrete using Gracilaria sp., Moringa oleifera, and honey (GMH) for column retrofitting. The research aimed to retrofit and improve the compressive strength and durability of broken columns submerged by tidal flooding by applying bio-polymer modified concrete with GMH. A field application of column retrofitting was conducted in areas prone to tidal flooding. The retrofitted columns performance was observed for 14 months and validated by non-destructive and destructive tests. The result showed that the compressive strength of the retrofitted column achieved 32.37 MPa, which is a 92.34% increase compared to the baseline. This research provides answers to the challenge of concrete materials sustainability by promoting bio-polymer modified concrete that significantly increased its performance and long-term durability using GMH. [ABSTRACT FROM AUTHOR]

Two different test systems were designed to evaluate the tribological behavior of five engineering plastics (Polyamide—PA grades and Ultra High Molecular Weight Polyethylene—UHMW-PE) and a fully degradable bio-composite (Polylactic Acid—PLA/hemp fibers) targeted to agricultural machinery abrasive conditions. Pin-on-plate tests were performed with different loads, sliding velocity and abrasive particles. The material response was further investigated in a slurry containing abrasive test system with different sliding velocities and distances, abrasive media compositions and impact angles. The abrasive wear, the change of the 3D surface roughness parameters, the friction force and contact temperature evolution were also analyzed as a function of the materials' mechanical properties ( H , E , σ y , σ c , ε B , σ F , σ M) and the dimensionless numbers derived from them. Using the IBM SPSS 25 software, multiple linear regression models were used to statistically evaluate the measured data and to examine the sensitivity of the material properties and test system characteristics on the tribological behavior. For both test setups, the system and material characteristics influencing the dependent variables (wear, friction, heat generation) and the dimensionless numbers formed from the material properties were ranked using standardized regression coefficients derived from the regression models. The abrasion sensitivity of the tested materials were evaluated taking into account a wide range of influencing parameters. [ABSTRACT FROM AUTHOR]