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Cellulose is commonly acknowledged as a sustainable material owing to its abundance and renewability. However, the abundance of hydroxyl groups makes the paper material highly hydrophilic, and the hydrogen bonds between the fibers are easily broken by water, leading to the degradation of mechanical properties. This work details the fabrication of a composite paper comprising interwoven cellulose and polylactic acid (PLA) structures through hot‐pressing and PLA impregnation onto handwritten paper derived from conventional wood pulp fibers as the substrate. The investigation assessed how varying PLA concentrations influenced the overall characteristics of the composite paper, including its morphology, structure, mechanical properties, water absorption behavior, and water contact angle. Experimental results revealed that the composite paper fabricated through our approach exhibited an intertwined structure comprising both PLA and cellulose. With a tensile index reaching 33.24 kN·m/kg and a mere 31.1% loss in tensile index post‐water treatment, the mechanical properties of the composite paper were significantly enhanced due to the robust interfacial compatibility between cellulose and PLA, as well as the adhesive effect of PLA. Furthermore, the composite paper (CP) is easily processable and amenable to thermoforming into paper trays as required, indicative of its potential applications in the packaging industry. [ABSTRACT FROM AUTHOR]

Regenerated cellulose membrane is a biomaterial obtained by activating, dissolving, solidifying, and regenerating cellulose powder using solvents of different polarities. It has the characteristics of high oxygen resistance and high strength. However, its low water vapor barrier and single function limit its application. In order to improve the water resistance of regenerated cellulose membranes and endow them with UV resistance, lignin was extracted from waste wheat straw using formic acid method. The extracted formic acid lignin (FAL) was added to the cellulose solution to prepare a series of regenerated lignocellulosic membranes (RC‐FAL) with different lignin contents. The results indicate that lignin can not only improve the water vapor barrier, tensile strength, and water resistance of the film, but also enhance the oxygen barrier and UV absorption of the film. Compared with pure cellulose film, the contact angle of lignocellulose film can be increased by 66.2%, the UV absorption rate can reach 100%, and the oxygen transmission coefficient has no significant effect. In this paper, a new kind of biological packaging material with high oxygen resistance, strong ultraviolet absorption, and water resistance was prepared by recycling waste wheat straw, it has a broad application prospect in the industrial production of packaging materials. [ABSTRACT FROM AUTHOR]

A transparent, bendable, high oxygen barrier cellulose‐based film was prepared, which has far better oxygen barrier properties than conventional polyethylene, polypropylene and cellophane materials. A series of regenerated cellulose films (RCs) were prepared from filter paper lacking oxygen barrier properties under different cellulose concentrations and gelation times. It was shown that the cellulose concentration and gel time had a greater effect on the oxygen barrier properties of RCs. When the cellulose concentration was 4 wt% and the gel time was 3 h, the RCs obtained the lowest oxygen permeability coefficient (OPC) down to 2.21 × 10−17 cm3 cm cm−2 s−1 Pa−1. The films have a tensile strength of 109.5 MPa, an elongation at break of 27.3% and a light transmission rate of 89%. In further, molecular dynamics simulations showed that when the filter paper was converted to RCs, the increase in hydrogen bonding and the decrease in free volume between cellulose chains caused a decrease in the diffusion coefficient of oxygen. As a novel biobased high oxygen barrier material, the film has broad application prospect in packaging and chemical industry. [ABSTRACT FROM AUTHOR]

Thermosensitive polymer artificial muscle fiber filaments made of two polymers, cyclic olefin copolymer elastomer (COCe) and polyethylene (PE), have the ability to sense changes generated by the external environment temperature. To optimize the thermosensitive polymer performance, this work investigates the effects of heating temperature, tensile load, strain rate, and mix proportion applied to COCe‐PE polymers on mechanical properties of the resulting fiber‐based muscle. The fiber filament deformation, stress distribution, and penetration characteristics are compared with multifactor coupling parameters utilizing a computational fluid dynamics simulation model. The simulation results show that although increasing the heating temperature has a small effect on the deformation of the fiber filaments, the interpenetration between the materials is better improved with the increase of temperature. Increasing the tensile load and strain rate can effectively increase the fiber filament deformation and improve the interpenetration between materials. The mix proportion of the two materials has a large effect on the plasticity and brittleness of the materials, and the different mix proportion also have a profound effect on the interpenetration. This study could provide some guidelines for the manufacture of artificial muscle fiber filament. [ABSTRACT FROM AUTHOR]

The pH‐responsive nanoparticles are a promising drug‐carrier because they always showed sensitivity and specificity to the pH changes caused by the surrounding environment. Most of the therapeutic drugs are generally absorbed in the stomach and small intestine due to the pH‐responsive nanoparticles always release the cargos at acidic media, making them difficult to reach the lower part of the large intestine, as well as inhibiting the therapeutic effects. Herein, an alkaline media‐sensitive supramolecular nanoparticle, regarded as SACD/PEI NPs, is prepared. SACD/PEI NPs exhibit assemble/disassemble state by changing the pH, which is used to encapsulate the anti‐colon drug CSL. CSL@SACD/PEI NPs showed a high release rate of 86.1% for the encapsulated CSL at pH = 8.5 (mimic the colon micro‐environment), while keeping stable at pH = 1.2 (mimic the gastric acid micro‐environment). Meanwhile, CSL@SACD/PEI NPs exhibited low hemolysis, indicating they possess good biocompatibility. In cell experiments, CSL@SACD/PEI NPs had a similar inhibitory effect on colon tumor cell SW480 and showed low cytotoxicity to normal cells compared with free CSL. Furthermore, both free CSL and CSL@SACD/PEI NPs showed excellent apoptosis effects on tumor cell SMMC‐7721. We hope that CSL@SACD/PEI NPs could be the valuable base‐answered drug delivery candidate, and have potential application for colon tumor therapy. [ABSTRACT FROM AUTHOR]

Heart failure (HF) is an irreversible disease characterized by the reducing capacity of blood supply as a consequence of cardiomyocyte death and deteriorated fibrosis. There is a lack of effective treatment for heart failure other than a heart transplant, and thus significant resources have been dedicated to developing functional materials for cardiac tissue engineering. Implanting hydrogels in the myocardium near the myocardial infarction area can preserve cardiac function and slow the remodeling that leads to HF by providing mechanical support to the ventricular wall. Nevertheless, few reviews have been published for this promising HF treatment. Herein, we briefly discuss the classification and existing conventional treatments for HF and provide an overview of recent functional hydrogels designed for cardiac repair after myocardial infarction, including polymeric hydrogels, polymer‐cell complex hydrogels, polymer‐cytokine complex hydrogels, and polymer‐protein complex hydrogels. Key challenges and future directions for advanced hydrogels have also been discussed. [ABSTRACT FROM AUTHOR]

Poly (lactic acid) (PLA) is a biodegradable and environmentally friendly material. And the spent coffee grounds (SCG) are huge waste all over the world. Therefore, the issue that how to convert the low‐value wastes SCG into more valuable products is attracting more research attention. In this work, we compounded PLA with SCG. Firstly, the efficiency of oil extraction from SCG was compared by different methods and solvents. Then, the biocomposites specimens of different SCG contents (0, 5, 10, and 15 wt%) were prepared by extrusion and injection molding. The effects of SCG particle size and content on the thermal and mechanical properties were investigated. Next, the effect of coupling agent (4,4‐methylene diphenyl diisocyanate [MDI]) on the biocomposites properties at 10 wt% SCG was examined by Field emission‐scanning electron microscope and Fourier transform infrared spectroscopy. The results show that the tensile strength and elongation at break of the PLA composites with the optimal contents are increased by about 50% and 120%, respectively, compared with untreated SCG. [ABSTRACT FROM AUTHOR]

Hyaline cartilage can be defined as a "biological bearing material" with an engineering approach. Movement causes friction between joints while lubricants provide separation between the two surfaces, reducing or preventing frictional wear. This study describes an injectable hybrid hydrogel consisting of a hyaluronic acid matrix filled with hexagonal boron nitride (hBN) particles that can mimic the rheological properties of joint fluid. hBN is a good lubricant and a strong candidate for biomedical applications with its unique tribological properties. The hypothesis established is that the lubricating property of hBN may alleviate the symptoms of osteoarthritis (OA) and improve the person's life quality. A new formulation and strategy for articular injections are proposed. The focus of the present work is the presentation of the rheological profile of hyaluronic acid‐boron nitride (HA‐hBN) hybrid hydrogels. Structural and physical characterizations have shown that BN‐HA hybrid hydrogels can be produced in injectable form, their compatibility with HA strongly depends on surface modification of BN, and they are promising candidates for the treatment of OA by evaluating the frequency range of walking and running. [ABSTRACT FROM AUTHOR]

Nanofibers and hydrogels are two forms of biomaterial scaffolds that have different properties and different applications. Polysaccharides have been used for the preparation of both scaffolds due to their biocompatibility and biodegradability. In this study, our main objective was to compare the tumor cell growth and tumor reduction potential of drug‐loaded scaffolds. This was achieved using different methods for cell proliferation, epithelial–mesenchymal Transition studies, and biomarker expression‐related assays. Anticancer drug doxorubicin was loaded to the scaffolds using adsorption and in vitro and in vivo tumor reduction was also performed. Results showed that both scaffolds supported the growth of cancer cells but did not promote epithelial‐mesenchymal transition. A significant difference in drug release was observed and this may have influenced the in vivo tumor reduction. A fast release of the drug and higher tumor‐reducing potential was observed for hydrogel. The studies confirmed that different types of scaffolds have different properties. Biomedical applications related to the structure can be dissimilar in different scenarios. [ABSTRACT FROM AUTHOR]

This paper reported a facile and green method for surface functionalization of cellulose nanofiber (CNF) by oxidative polymerization of tannic acid (TA) and ethanediamine. The modified CNF (T‐CNF) was then used as filler for constructing polyvinylalcohol (PVA) composites. Experimental results suggested that the surface polar groups on CNF were increased after modification. The abundant surface polar groups allowed the homogeneous dispersion of T‐CNF in PVA matrix, and the formation of hydrogen bonds between fillers and matrix. This interfacial interaction and the high aspect ratio of T‐CNF have restricted the thermal mobility of polymer chains and increased the glass transition temperature and melting temperature of PVA. Tensile test suggested the good mechanical properties of composites, and the reinforcement effect of T‐CNF on PVA was better than that of un‐modified CNF. The good free radical scavenging ability of polymerized TA also improved the thermal stability of composites and endowed the composites with good antioxidant property. The T‐CNF/PVA composites with improved properties hold great promising applications in fields such as packaging, adhesive and coating. This work is expected to provide alternative and green approach for the surface modification of CNF and the preparation of multifunctional CNF composites with good properties. [ABSTRACT FROM AUTHOR]

Wheat straw (WS) was considered the most abundant agricultural residue in China. Therefore, it was meaningful to explore the effective utilization of WS. Thus far, WS has been considered a potential raw material to produce lignocellulose nanofibrils (LCNFs) with the rapid development of nanotechnology. Unfortunately, the existing methods of LCNFs preparation directly from WS still faced some hurdles. Herein, screw extrusion and ball milling considered the common mechanical pretreatments were employed to directly prepare LCNFs from WS. The different impacts of screw extrusion and ball milling pretreatments on the properties of LCNFs were revealed by systematically comparing physicochemical analyses. The results showed that the crystalline and chemical structure of samples was little affected by the mechanical pretreatment. However, the mechanical pretreatment caused a change in the morphology, yield, and chemical composition of LCNFs. LCNFs prepared by screw extrusion with a high yield of 73% had the narrowest diameter distribution (0 ~ 80 nm), the most cellulose content (51.1%), and the maximum crystallinity degree (44.7%). LCNF samples all exhibited good thermal stability. This work could not only offer theoretical guidance on the preparation of LCNFs by mechanical pretreatments but also expand the high‐value application of WS in polymer composites. [ABSTRACT FROM AUTHOR]

Due to biocompatibility and similar extracellular matrix structure, polyvinyl alcohol (PVA)/polyethylene oxide (PEO) nanofiber membranes are an essential medical dressing. However, the phase separation of the PVA/PEO composite system will occur within a short time. It severely limits the continuous preparation of PVA/PEO nanofiber membranes. To make PVA/PEO composite system maintain compatibility, a novel polyvinyl alcohol‐allyl polyethylene glycol (PVA‐g‐APEG) graft copolymer with phase change, compatibilization and biocompatibility was prepared successfully. Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) prove that the copolymerization and alcoholysis reaction allyl polyethylene glycol (APEG) and vinyl acetate (VAc) successfully obtained PVA‐g‐APEG graft copolymer. The prepared PVA‐g‐APEG not only has electrospinability but can effectively prevent the phase separation of PVA/PEO composite system, which ensures the continuity of electrospinning in the industry. Additionally, the feasibility of the PVA‐g‐APEG compatibilized PVA/PEO composite system for application in biomedical was verified through the preparation and various assessments of PVA‐g‐APEG/PVA/PEO nanofiber dressings. The prepared PVA‐g‐APEG is beneficial to the PVA/PEO composite system to broaden its application in biomedical and other fields. [ABSTRACT FROM AUTHOR]

In this study, cross‐linked cellulose nanocrystals (CNC) were esterified using 1,2,3,4‐tricarboxylic acid (BTCA) to decrease the hydroxyl content of the nanocellulose, control its hydrophilic/hydrophobic degree, and improve its compatibility with the polypropylene (PP) matrix. The mechanical and physical properties of nanocellulose‐reinforced polypropylene composites were investigated after they were manufactured via melt extrusion using a twin‐screw extruder. FTIR and XPS analysis revealed that the nanocellulose chain was successfully esterified utilizing BTCA. The results from SEM and Mapping demonstrated that the nanocellulose was spread equally throughout the matrix. By characterizing the 5 wt% CNC/PP composite material with DMA and tensile testing devices, the elongation at break decreases, the rigidity increases, and the tensile strength increases to 50.5 MPa, a 25.5% increase over pure polypropylene. Simultaneously, DSC data demonstrated that nanocellulose provided a heterogeneous nucleation site, expedited polypropylene crystallization, and was advantageous for polypropylene processing. According to the results of TG/DTG, esterified CNC/PP composites containing 5% CNC had the highest thermal resistance, with Tonset and Tmax increasing by up to 66 and 11.6°C, respectively, when compared to pure PP. Following a thorough investigation and evaluation of the samples' mechanical and thermal properties, it was determined that BTCA esterification cross‐linking is an effective method for surface modification of nanocellulose, as it increases the compatibility of nanocellulose with polypropylene, improves the mechanical properties of polypropylene, and thus expands its application range. [ABSTRACT FROM AUTHOR]

The focus of this review is on the family of polymers commonly known as polyphthalamide (PPA), employed in the automotive industry along with other industries. This includes electrical parts, manufacturing or oil extraction because of PPAs chemical resistance, high strength, stiffness at high temperature, and dimensional stability. A significant amount of research was found and was divided into two main sections: first, PPA and its blends, and second, PPA composites. A consistent notation was devised to aid the understanding of older sources and enhance the comparison between different materials, increasing comprehension. Undiscovered or unpublished properties of PPAs means that there is a rich vein of opportunity, and many studies yet to be performed. This will open up a plethora of breakthrough research in electrical vehicle and aerospace applications. [ABSTRACT FROM AUTHOR]

The residual resistance factor (RRF) is an important parameter expressing the mobility control capability of the polymer, and it is related to the polymer molecular structure. This study investigated the ability of three polymers with different molecular structures to establish RRF in a one‐dimensional sand pack model at different permeabilities. In addition, the static adsorption capacity of the three polymers on the rock surface was investigated, and the mechanism of the polymer retention in porous media was explored by changing the wettability of the rock surface. Furthermore, the microscopic morphological changes of the polymers before and after passing through the porous media were observed by environmental scanning electron microscopy. Finally, nuclear magnetic resonance core flooding experiments were used to investigate the oil displacement characteristics of the three polymers in the core. T Results show that the ability of the three polymers to establish RRF gradually decreases with the increase in permeability. Still, the modified chitosan hyperbranched polymer (HPDACS) has the best ability to establish RRF in porous media with the largest static adsorption equilibrium amount of 1249 μg/g. Mechanical capture is the dominant mechanism for HPDACS to establish retention in porous media. In addition, HPDACS has a better ability to enhance recovery. It can improve oil recovery by 20.43%, which is higher than that by dendritic polymer HPDA at 16.34% and partially hydrolyzed polyacrylamide at 10.07%. HPDACS can establish a larger resistance in the macropores of the core. Thus, the remaining oil is better driven in the medium and small pores. This finding indicates that HPDACS has excellent potential for oil displacement. [ABSTRACT FROM AUTHOR]

Novel electroactive hydrogels were fabricated from carboxymethyl cellulose (CMC) biopolymer incorporated with conductive polythiophene (PTh). The PTh particles dispersed uniformly in the CMC matrix providing higher mechanical properties and thermal stability. The formulation CMC/PTh6 (6%wt PTh) gave the highest tensile strength and elongation at break (0.9456 ± 0.0017 MPa and 123.0398 ± 7.0606%, respectively). The bending response of the hydrogels under an applied electric field was studied in terms of bending angle and bending sensitivity. Under an electric field strength of 100 V mm−1, CMC/PTh10 (10%wt PTh) showed the highest bending angle (52.245 ± 6.054°) while neat CMC gave the lowest bending angle (33.753 ± 8.116°). The bending behavior upon the application of an electric field of the CMC/PTh hydrogels occurs from the polarization of Na+ and H+ in the CMC matrix and S+ in PTh. [ABSTRACT FROM AUTHOR]

This study focused on modeling and optimization of the concentration of poly (vinyl alcohol) (PVA), cellulose nanocrystals (CNC), snail shell nanoparticles (SSN), and glycerol for the development of bioplastic films. The response surface methodology using Box–Behnken experimental design was used to investigate the effect of the independent parameters (additives concentrations) on the ultimate tensile strength and Young's modulus of fabricated bioplastic films. A varied ultimate tensile strength and Young's modulus with different component loadings was observed, proving the effect of nanoparticles loading effect on the mechanical properties of bioplastic films. The quadratic polynomial model experiment data provided a coefficient of determination (R2) of 0.795 for ultimate tensile strength and 0.732 for Young's modulus, evidencing the fitness of the models to pilot the optimization space. The optimum parameters were PVA (7.820%), CNC (1079%), SSN (1241%), and glycerol (2.657%). The ultimate tensile strength and Young's modulus of 27.2 MPa and 31.2 MPa were obtained for the developed bioplastic film with optimized concentrations of each component. The bioplastic films showed improved thermal stability and degradation. The scanning electron microscopy (SEM) imaging revealed a homogeneous dispersion of SSN and CNC in the matrix, which explained the improved properties observed. [ABSTRACT FROM AUTHOR]

Huge quantities of wastewaters are produced during dyeing of textile, which is why wastewater treatment plants are required in textile industries in which, in most cases, non‐dyed filaments are produced first and dyeing of these filaments is performed at a later stage. Here, carboxymethylated cellulose (CMC) with the COOH group content of 1.3 mmol/g CMC was covalently crosslinked through reactive green 19 dye in the dope solution (0.09 wt% dye with reference to CMC) from which green textile filaments were spun. The incorporation of dye in the dope solution has the advantage of obtaining dyed filaments without using an additional step for dying of the fabricated textile filaments and, moreover, it can be done in such a way that clean, no dye containing wastewater is produced. The filaments also demonstrated an increase in mechanical strength (tenacity ~ 0.96 cN/dtex) and a decrease in water absorbency (water absorbency ~ 0.63 g water/g filament) due to chemical crosslinking of cellulose chains through the dye. Owing to covalent bond formation between the CMC and the dye, excellent color fastness properties were obtained for the fabricated filaments. [ABSTRACT FROM AUTHOR]

With the advancement of applications in biomedicines and bioelectronics, conducting polymers have attained huge significant attention. For such applications, poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is considered a potential conducting polymer because of its low cost, considerable stability, high conductivity and mechanical strength. Most importantly, its easy aqueous solution processability makes it more attractive. Over the last few years, PEDOT:PSS has been predominantly explored and investigated for different optoelectronic flexible devices, and recently it has been studied for biomedical applications. PEDOT:PSS based materials have made progress in biomedicines due to their properties such as biocompatibility, cell proliferation, antibacterial, nontoxicity and so forth. To adjust the desirable properties, special attention is required for altering the structure of PEDOT:PSS material. PEDOT:PSS offers excellent antibacterial properties against both gram‐positive and gram‐negative bacteria. Moreover, PEDOT:PSS demonstrates an important role in sensing human body humidity, pressure control, glucose detection, as well as employed in human sweat sensors. Besides these, PEDOT:PSS has been studied as a scaffold for endothelial cell preservation. There are several issues which need to be resolved in the future, such as improved biocompatibility and stability to explore the PEDOT:PSS based composite materials in biomedical applications. However, a related review article is lacking, directed on the PEDOT:PSS biomedical applications, namely, antibacterial, tissue engineering, and biosensing. Therefore, the current article summarizes importance of PEDOT:PSS for biomedical applications, and main emphasis is given to its recent advances, challenges and perspectives. [ABSTRACT FROM AUTHOR]

In this review, the focus of discussion is the polysaccharide fraction of cashew gum (CG), an exudate of Anacardium occidentale L., a plant typical of hot and humid tropical climates commonly found in northeastern Brazil and from which cashew nuts are extensively commercialized. CG purification, biological activity, and physical–chemical properties are explored in this work, in addition to applications of this biopolymer as a component of biomaterials used to either support, enhance, or replace damaged tissues or improve biological function. Evidence of its successful use to produce a range of biomaterials, from particles to gels and films, and to improve properties of already existing formulations are provided, supporting its versatility in this field of application. [ABSTRACT FROM AUTHOR]

The article reviews the different methods of which, phytic acid (PA) can be employed as a flame retardant (FR) filler for different polymeric materials. The methods are critically discussed, based on the available literature and patents. Depending on the method used and the addition of FRs into a PA flame retarded system, different flame retarding modes of action and fire resistance performances are attained. The mechanism of action for PA‐based system remains similar to those observed in other phosphorus‐based FRs, namely, condensed and gas‐phase mechanisms. [ABSTRACT FROM AUTHOR]

Active food packages must not only act as a protective food barrier but also exhibit radical scavenging activity, antibacterial and controlled release properties that can have a positive effect on food quality, safety and shelf life. In this study, poly(ε‐caprolactone) (PCL)/ferulic acid (FA) and PCL/gallic acid (GA) biocomposites were prepared by melt blending method to use in active food packaging applications. The physicochemical properties of the prepared biocomposites were investigated by FTIR‐ATR, SEM, and DMA. In addition, antioxidant and antibacterial activities, water contact angle, oscillation test and water vapor transmission rate of biocomposites were also investigated. FTIR‐ATR and SEM results showed that both fillers were well dispersed in the PCL matrix. Dynamic mechanical analysis was performed to examine the mechanical behavior of the samples and to determine their Tg temperatures. The biocomposites exhibited a higher storage modulus and loss modulus than pure PCL. Especially, the glass transition temperature of the PCL/FA sample containing 5 wt.% FA increased 17°C compared to the neat PCL. They exhibited high‐scavenging activity against DPPH and ABTS radicals, and showed high‐antibacterial activity against both E. coli and S. aureus bacteria. [ABSTRACT FROM AUTHOR]

Biopolymer nanoparticles (NPs) produced from poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBV) are typically formed by first dissolving the polymer in organic solvents. In order to eliminate the use of toxic solvents, an alternative "green" solvent system using glacial acetic acid was used in this study for the preparation of NPs via nanoprecipitation. The influence of various factors on the resulting particle size was investigated including the use of an emulsifying agent, temperatures of stock and receiving solutions, and concentration of stock solution. The addition of emulsifier significantly reduced the NP size, whereas temperature had minimal influence on the particle size over the tested range. By varying the concentration of the stock solution, the size of the NPs can be adequately controlled. The minimum size of NPs prepared using a stock solution of 0.5 ml at 80°C into a 100 ml receiving solution was 70 nm with a narrow size distribution. Imaging by scanning electron microscopy revealed smooth spherical NPs and thermal and structural analysis showed only minor changes in properties in comparison with the source PHBV powder. Overall, the results show that glacial acetic acid is an appropriate alternative solvent for the dissolution of PHBV and the subsequent formation of biopolymer NPs. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) is a biodegradable polymer used in films production; however, it has some limitations. Thus, strategies can be used to improve the characteristics of these materials such as the incorporation of starch nanocrystals (SNCs). Therefore, the aim of this study was to add potato and rice SNCs in PLA matrix in the melt to obtain PLA films with structural reinforcement to improve its properties. The SNCs were produced by acid hydrolysis and incorporated to the matrix in 0.5 and 1 wt% amounts. The films were then produced by bioriented tubular extrusion and characterized with several techniques. Films containing 1 wt% of potato SNCs showed an increase in tensile strength, elongation, and glass transition temperature, but a reduction in water vapor permeability. Therefore, the use of potato SNCs as a structural reinforcement for PLA films improved the properties of the films making them suitable candidates for several other applications. [ABSTRACT FROM AUTHOR]

Large bone defects due to accidental injuries and fractures as well as the mismatch between the implant material and the defect site are major problems in biomedicine. Bone tissue engineering offers a solution to this problem. In this paper, a series of three‐dimensional porous composite scaffolds with shape memory were prepared using polycaprolactone and polytetrahydrofuran as soft segment materials, hexamethylene diisocyanate as hard segment materials and amorphous calcium phosphate/calcium citrate (CAP) as inorganic fillers. The scaffolds have tunable mechanical properties, melt temperature, surface wettability, a pore size range of 100–800 μm and a high degree of connectivity. In vitro mineralization showed good mineral deposition and energy dispersion spectrometer displayed uniform distribution of Ca and P elements on the surface. The composite scaffold exhibited good shape memory properties at 37°C. The shape fixation rate (Rf) and shape recovery rate (Rr) were maintained at 94.1% and 94.4% after five compression cycles. The resulting scaffold promoted MG63 cell proliferation to some extent. The scaffold is expected to be used clinically for the treatment of large bone defects. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HAp)‐polymer composite materials are of interest for materials that interface with or substitute bone tissue. HAp nanoparticles (length 290 nm, width 56 nm) synthesized by a wet chemical method were incorporated (5 wt%) into natural rubber latex (NRL), poly lactic acid (PLA) and NRL/PLA (75/25) solvent cast films using three different methods: dry nanoparticles; a dispersion prepared from dry nanoparticles; a dispersion prepared through solvent exchange. Common to all composite materials were an improvement in the contact angle by 10%–13% and a reduction in the elongation at break from 430% to 330%–370%. Furthermore, the method of HAp incorporation influenced the properties of the material with the use of dioxane suspension improving the homogeneity of the films as evidenced from visual appearance and SEM. This led to slower water uptake and higher thermal stability with a shift in the PLA melting peak from 296°C to 334°C when compared to pure polymer and composites with poorly dispersed particle. [ABSTRACT FROM AUTHOR]

Bio‐based epoxy resins with low‐dielectric constant, low viscosity and excellent mechanical properties have great significance for the future of advanced electronic and microelectronic industries. Cyclosiloxane segment possesses low polarity, high‐dissociation energy, and elevated molecular volume, thereby making it useful for the synthesis of materials with low dielectric constant and viscosity. Herein, a tetrafunctional eugenol‐based epoxy resin (DEP) based on a cyclosiloxane structure was designed and prepared through a hydrosilylation reaction. Allyl glycidyl ether (AGE) was selected as a reference compound and generated a silylation epoxy resin (AGDEP). The viscosity of these silicone‐containing tetrafunctional epoxy monomers (< 0.315 Pa·s) was significantly lower than that of the conventional oil‐based epoxy resin (14.320 Pa·s). After curing with methyl hexahydrophthalic anhydride (MHHPA), the dielectric constant of DEP‐MHHPA was as low as 2.8 (10 MHz), which was superior to that of EP‐MHHPA. Notably, the glass transition temperature (Tg) of DEP‐MHHPA was as high as 100.3°C. The tensile strength and elongation at break of DEP‐MHHPA were estimated to be 66.1 MPa and 6.0%, respectively. Multifunctional eugenol‐based epoxy monomers with low‐dielectric constant and viscosity provide an efficient guideline for building epoxy‐based materials to better design future‐oriented engineering materials. [ABSTRACT FROM AUTHOR]

As a special structure and due to the unique properties of submicron‐scale fibers and electrical conductivity, conductive nanofibers recently attracted further attention in various fields, especially tissue engineering. This study aimed to coat poly (glycerol sebacate) (PGS) nanofiber/poly(caprolactone) (PCL) as a widely used combination in the fields of medicine with poly(pyrrole) (PPy) as a conductive polymer, subsequently studying and optimizing production process variables using response surface methodology (RSM). The samples were examined for morphological and structural, and their electrical conductivity and electroactivity were measured using a four‐point probe system and a cyclic voltammetry, respectively. The electrospinning conditions for constructing the substrate nanofibers with the smallest diameter were optimized. The monomer concentration of 0.05M and the polymerization time of 3.3 h exploiting the RSM were also considered as the optimal conditions for obtaining coated‐nanofibers with the smallest diameter and desired electrical conductivity (0.001 S/cm). The structural findings confirmed the successful synthesis of PGS and PPy. The conductive‐nanofiber produced under optimal conditions revealed good mechanical properties (tensile strength = 3.12 ± 0.19 MPa and elongation at break = 80.26 ± 13.71%). The highest biocompatibility was observed for the sample synthesized with the pyrrole concentration of 0.05M, which can be a suitable candidate for application in cardiac tissue engineering. [ABSTRACT FROM AUTHOR]

Polymer microspheres are widely used as carriers in delivering of hydrophobic or hydrophilic drugs. Surface coating of microspheres could be one of the attractive strategies to improve their properties. In this study, biodegradable polymer polylactic acid was dissolved in chloroform and non‐solvent to electrospray porous polymer microspheres. The properties of the microspheres were improved by phosphoglyceride (P‐P‐Gly) coating, and its behavior was investigated by loading with curcumin as a model drug. The morphologies of different microspheres were observed by scanning electron microscope. The results indicated that the microspheres obtained by dimethyl sulfoxide as non‐solvent could form the structure with porous characteristics. X‐ray diffraction, X‐ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy analysis revealed that P‐P‐Gly was successfully coated on the surface of the microspheres. In addition, the thermal behavior of the coated microspheres was investigated by differential scanning calorimetry. In vitro release experiments indicated that the drug‐loaded microspheres showed a very gentle release trend, which was mainly due to the P‐P‐Gly coating could not completely cover the pores of the microspheres. The P‐P‐Gly‐coated microspheres prepared in this work can be used as controlled release drug carriers with special needs. [ABSTRACT FROM AUTHOR]

Not only are the physicochemical properties and biocompatibility of biomaterials important considerations, but also their antibacterial properties. Fetal cowhide acellular dermal matrix (FADM), as a collagen scaffold with good biocompatibility and bioactivity, is difficult to be used to promote wound healing due to lack of sufficient mechanical strength and resistance to degradation. In order to solve this defect and give it long‐lasting antibacterial properties, a novel chemically‐cross‐linked antibacterial fetal cowhide acellular dermal matrix scaffold (β‐CD/TTO‐FADM) was fabricated by simultaneous modification by oxidized cyclodextrin (OCD) and tea tree oil (TTO). The cross‐linking of OCD improved the physical and chemical properties of FADM. TTO endowed it wide‐spectrum antibacterial activity against Escherichia coli and Staphylococcus aureus. Apart from this, the drug‐carrying capacity of OCD could also control the release of the TTO, and made the antibacterial ability durable and temperature sensitive. In addition, cell experiments and animal experiments showed that β‐CD/TTO‐FADM had good biocompatibility and could accelerate the wound healing process. Overall, an improved wound dressing with antibacterial properties that can be used in clinics has been developed, and it has also provided ideas for the development and application of drug‐loaded crosslinking agents. [ABSTRACT FROM AUTHOR]

Natural rubber‐latex compounds were embedded with glass fibers as a sandwich layer to modify the thermal‐ and sound‐absorption properties of plaster sandwich‐panel composites by casting. The physical, thermal, mechanical, and sound‐absorption properties of the composites were compared to those of the commercial gypsum ceiling according to the American Society for Testing and Materials and Thai Industrial Standards. The optimum sample was a plaster sandwich‐panel composite with 20 wt% natural rubber‐latex compounds, 10 wt% NaHCO3, and 10 wt% tissue paper (PN0‐2010‐10). It exhibited low‐bulk density (0.7504 g/cm3), low‐thermal conductivity (0.0775 ± 0.0005 W/m.K), good noise‐reduction coefficient (NRC) (0.2142), and a high percentage of sound‐absorption coefficient (56.02%) at a low frequency of 500 Hz. On the other hand, the reference sample (P0‐0‐0) exhibited high‐bulk density (1.1363 g/cm3), high‐thermal conductivity (0.3387 ± 0.0003 W/m.K), low NRC (0.1381), and a low percentage of sound‐absorption coefficient (10.07%) at a low frequency of 500 Hz. Therefore, the obtained plaster sandwich‐panel composites are promising as building materials for the protective and decorative coating of walls and ceilings. [ABSTRACT FROM AUTHOR]

In this study, a novel cryogel scaffold loaded with styrax liquidus gum exuded from trank of Anatolian sweetgum (Liquidambar orientalis Mill.), with antimicrobial and antioxidant properties was developed for potential tissue engineering applications. For this purpose, different ratios of styrax incorporated chitosan/polyvinyl alcohol composite scaffolds were fabricated using cryotropic gelation method. The effect of styrax incorporation onto the cryogel network was evaluated using morphological and physico‐chemical analyzes. The characterized cryogels were also investigated in detail for their antioxidant activity, anti‐biofilm, antimicrobial, and DNA cleavage properties. The styrax incorporated cryogels can be candidate biomaterials for tissue engineering applications, in particular for antimicrobial systems due to their ferrous ion chelating activity and high antioxidant, anti‐biofilm, and antimicrobial properties. [ABSTRACT FROM AUTHOR]

Self‐healing polymer materials have been developed rapidly over the past 20 years, which can replace thermosetting materials to a certain extent, repair damage without manual intervention, prolong service life, and compress usage cost. The self‐healing polymer materials derived from biomass resources can reduce the dependence on traditional non‐renewable resources such as petroleum. The structures and properties of biomass based self‐healing polymer materials are of great significance for their processing, recycling and self‐healing. In this paper, the research progress of bio‐based self‐healing polymer materials based on dynamic non‐covalent bonds and dynamic covalent bonds including hydroxyl ester, Schiff base, disulfide bond, and hydroxyl urethane derived from vegetable oil, lignin, cellulose, vanillin and natural rubber were reviewed, and the dynamic non‐covalent bonds and dynamic covalent bonds were also introduced. The applications of various dynamic covalent bonds and dynamic non‐covalent bonds in the design and construction of polymer materials were reviewed, and the future development of dynamic covalent polymer materials was prospected. [ABSTRACT FROM AUTHOR]

The most effective approach for wound healing improvement is entrapping and controlling the oxygen in a biocompatible polymer matrix through introducing hydrogen peroxide. In the research, the bacterial cellulose (BC) layers were oxygenated as a safe and excellent hydrogel to accelerate the wound healing process. Indeed, the hydrogel‐containing hydrogen peroxide was obtained using the treatment of dry BC with 3% hydrogen peroxide for 5 h. The morphology, thermal behavior, crystalline and chemical structures, mechanical properties, water vapor permeability, degree of porosity, oxygen release, water holding capacity, and drying time of the treated layers were investigated. Furthermore, the calculated porosity showed about seven times more pore area. The dissolved oxygen results indicated the well‐trapped oxygen in BC with a prolonged‐release time of 20 days. Moreover, the 100% antibacterial and antifungal activities and excellent wound healing properties without cytotoxic effects specified the ability of BC to trap and release oxygen for efficient wound healing. Hence, the study introduces a functionalized naturally driven hydrogel layer with oxygen delivery, safe antimicrobial properties, and prolonged drying time. [ABSTRACT FROM AUTHOR]

Although biodegradable and biocompatible polymers have great advantages as a research hotspot, the single polymer does not satisfy multifunctional needs in biomaterials application. Herein, carbon dots (CDs) with strong fluorescence and good hydrophilicity were prepared through effective microwave method from citric acid and ethanediamine. Then green PCL@CDs biomaterials were fabricated by the ring‐opening polymerization (ROP) of ε‐caprolactone (ε‐CL) via green phytic acid and active CDs as catalysts. Importantly, the as‐obtained PCL@CDs hybrids with good biocompatibility, adjustable hydrophilicity and good fluorescence could load antituberculosis rifapentine (RFT) by the method of oil/water emulsion solvent evaporation. Also, the morphology, RFT loading and release activity of PCL@CDs@RFT microspheres were deeply investigated. The results showed that the maximum drug loading and encapsulation rate of the prepared PCL@CDs@RFT microspheres were 7.8% and 81%, respectively. Therefore, the binary material can be used as a kind of potential fluorescent labeling biomaterial for drug delivery. [ABSTRACT FROM AUTHOR]

In this study, regenerated Antheraea mylitta silk fibroin (ASF) and polyvinyl alcohol (PVA) dissolved in formic acid were blended together in variable ratios to prepare blend films. The blend films presented homogeneous morphology with no visible phase separation as observed in scanning electron microscope (SEM). The structural analysis of blend films through fourier transform infrared spectroscopy and X‐ray diffraction indicated the formation of co‐crystals due to interaction of fibroin with PVA molecular chains. The thermal properties assessed using thermogravimetric analyzer and differential scanning calorimeter supported the molecular interactions with altered thermal stability of blend films. Incorporation of PVA into ASF enhanced the mechanical properties of blend films. The water uptake capacity, biocompatibility and biodegradability were analyzed. The L929 fibroblast skin cells seeded on blend films were found to have attached the film surface and started attaining their conventional morphology after 48 h, as observed under SEM. Alamar blue assay confirmed the cytocompatibility of blend films with more than 95% cells being viable. Based on the aforementioned encouraging results, we can assert the utility of these blend films in biomedical field for tissue regeneration applications. [ABSTRACT FROM AUTHOR]

Fused deposition modeling (FDM), one among the most commonly used additive manufacturing (AM), techniques has been widely used in recent years to produce customized parts with intricate geometries, especially from thermoplastics. This method was limited in its ability to produce parts for industrial applications due to inferior properties and the poor quality of fabricated parts. Hence, researchers are being driven to discover novel materials that are viable for FDM in order to keep up with enormous demand for functional products. In the recent years, it is widely recognized that the emphasis was placed on the bio‐based polymer composite matrices rather than conventional thermoplastics due to its vital advantages that aid in the replacement of synthetic and perilous materials. On this context, this review focuses on the recent advancements in FDM printing with biomaterials. Specifically, attempts have been made to investigate and provide nutshell of 3D printing of current bio‐based nanocomposites which consist of either bio‐derived filler or polymer matrices in order to make 3D printing sustainable. The effect of fillers on the filaments and FDM based products, evolution of novel characteristics of bio nanocomposites, the printability of the developed composites and their development in leading applications were also investigated and summarized. [ABSTRACT FROM AUTHOR]

In this work, the effect of an expansin‐like cerato‐platanin (CP) protein as a pre‐treatment for the enzymatic hydrolysis of bacterial cellulose (BC) is investigated. To this scope, cellulases from Trichoderma reesei are used as hydrolyzing agent using different enzyme/BC formulations. Turbidity experiments reveal that for the higher enzyme concentrations (formulations 0.5:1 and 1:1) the enzymatic hydrolysis of BC show similar hydrolysis kinetics and is not dependent of the CP. However, at higher BC concentrations (formulations 0.25:1 and 0.33:1), the hydrolysis of BC is hindered by the non‐catalytic protein, as confirmed by the lower content of cellobiose and glucose in the presence of CP. Light scattering experiments show that the addition of CP led to an increase of the BC particle size from (445–630 nm) to (890–1.26 μm) for the formulation 1:1, which is also corroborated by atomic force microscopy and transmission electron microscopy analyses. These results suggest that CP did not positively affect the hydrolysis of BC, in contrast to what was previously observed for plant‐derived cellulose. This work for the first time investigates the anomalous behavior of cerato platanin family members with regard to its loosening activity on the structure of bacterial cellulose. [ABSTRACT FROM AUTHOR]

The hydrophobic modification of cellulose nanofibers (CNF) was carried out via free radical polymerization using methyl methacrylate (MMA) as the monomer to improve the compatibility between CNF and poly lactic acid (PLA). Followed by the preparation of the novel nanocomposites in combination of the organic montmorillonite and the substrate. The resulting nanocomposites were then coated on paper surface using a cast‐coating process in an attempt to improve the barrier properties towards water vapor and oxygen. In addition, the composite films are prepared via a solution casting method. The water vapor transmission rate (WVTR), water vapor permeability (WVP), oxygen transmission rate (OTR), and tensile strength of the as‐prepared films were systematically measured. The corresponding results demonstrated that the WVTR, WVP and OTR decreased with the addition of a certain content of MCNF in coatings. 0.2 wt% MCNF is the optimum content, showing the best gas resistance and tensile performance. The lowest value of WVTR and WVP are 10.30 g/(m2⋯24 h) and 3306.58 g⋯μm/(m2⋯24 h) for films with 0.2 wt% MCNF added, which is 88.23% and 26.05% lower than that of PLA composite film without NFC. [ABSTRACT FROM AUTHOR]

The current research project is dedicated to tackling the issue of fiber alignment and composite material delamination. Alkali treatment is performed to enhance the bamboo filler reinforced composite's mechanical performance as well as interfacial bonding strength. The hybrid composite is developed with varied bamboo powder content from 2.5 to 12.5 wt% and graphite nanoplatelets (GN) are reinforced in the polymer matrix. The hybrid composite is manufactured with bamboo powder approximately 65 μm sized and GN for electrical and electronics packaging, heat sink, conductive paste, light back cover for thermal management, automobile parts, and packaging goods. The developed material is investigated experimentally through the tensile test, modulus of elasticity, storage modulus, thermal conductivity, corrosion and tribological analysis. Results revealed that 5 and 7.5 wt% bamboo filler with 1 wt% GN gives the best property among others. [ABSTRACT FROM AUTHOR]

Bagworm silk (BS) is the strongest natural fiber as known. We present the development of a bagworm‐based conducting synthetic/natural fiber composite for creating a flexible and strong textile. Fourier‐transform infrared spectroscopy, reflection UV–vis spectroscopy, scanning electron microscopy, electron spin resonance, and a superconducting quantum interference device (SQUID) were used to evaluate the composite. BS/PANI sheet resistivity was 1.0 × 102 kΩ/cm. The electrical conductivity measurements and magnetic measurements evaluated that the charge carriers of the composite were radical cations (polarons) of polyaniline. [ABSTRACT FROM AUTHOR]

A new bio‐based epoxy resin (BER) is produced by the esterification reaction between sebacic acid (SAc) as bio‐based acid and epichlorohydrin (ECH). The epoxy resin (ER) is modified with the BER. The biocomposites are prepared using untreated coconut shell powder (CSP), modified coconut shell powder (MCSP), and MER. The CSP and MCSP particles are mixed with MER in varied compositions (10–50 wt%) for preparation of the MER/CSP and MER/MCSP biocomposites. The influences of CSP and MCSP bio‐fillers amounts on the physical properties (density, elastic constants, acoustic impedance, ultrasonic micro‐hardness, and attenuation coefficient) of biocomposites are investigated using the ultrasonic pulse‐echo overlap method (PEOM). It was seen that the densities, both ultrasonic longitudinal and shear waves' velocity values of obtained biocomposites were higher than those of the MER. All elastic moduli of the MER/MCSP biocomposites have higher values than of the neat MER and MER/CSP biocomposites. [ABSTRACT FROM AUTHOR]

In this study, polylactic acid (PLA)/sulfadiazine sodium/proteinase K composite nanofibers were prepared by electrospinning, and their morphology was observed by scanning electron microscope. The novel nanofibers were characterized by Fourier transform infrared spectroscopy and drug release curve. The activity of different groups of drugs loaded nanofibers in frostbite wound of rats was studied and compared with the blank control group. Hematoxylin–eosin staining and transmission electron microscope were used to access the histological changes of frostbite wounds on the back of rats before and after treatment. CD31 fluorescence staining was used to track the reconstruction and improvement of blood vessels in tissues. The results revealed that the drug release rate of PLA/sulfadiazine sodium/proteinase K nanofibers group was more than 50% at 1 h, and the cumulative drug release rate was more than 88% at 168 h, and CD31 fluorescence showed that its vascular density was 13.27% ± 0.9%, which was significantly higher than that of other groups. Therefore, PLA/sulfadiazine sodium/proteinase K composite nanofibers could promote the healing of frostbite wounds, which indicated the increase of capillaries and the regeneration of hair follicles. PLA/sulfadiazine sodium/proteinase K composite nanofibers have great potential in the application of frostbite. [ABSTRACT FROM AUTHOR]

Nanoparticle enhancement has been used as an effective means to improve the performance of biomass adhesives. However, there is an inevitable problem of stress concentration caused by particle agglomeration and thus the adhesive layer is susceptible to damage. Therefore, in this paper, a sol–gel method was used to generate uniformly distributed manganese dioxide (MnO2) nanoparticles on the surface of diatomite (Dia) and used for the modification of soybean meal based wood adhesives. The results showed that MnO2 nanoparticles have been successfully anchored on the surface of Dia during the sol–gel process without agglomeration. MnO2/Dia particles could fill in the adhesive gaps and form hydrogen bonds with soy protein molecules, which ensured that the adhesive wet shear strength was increased by 33% to 0.89 MPa. This study provided an idea for the preparation of highly dispersed nanoparticle reinforced adhesives. [ABSTRACT FROM AUTHOR]

Three‐dimensional (3D) printing is a rapidly growing technology and plays an emerging role in several biomedical applications. Polylactic acid (PLA) is one of the most common materials in 3D printing, however, it is chemically inert due to the absence of reactive side chain groups. In this context, in this work, the PLA scaffolds with two different geometries were produced and coated with natural rubber latex (NRL) extracted from the rubber tree Hevea brasiliensis. NRL presents bioactive substances that are related to its biological properties. The results revealed scaffolds with interconnected pores and pores sizes from 600 to 1300 μm. The NRL coatings caused a decrease in pore size. Infrared spectra showed that 2 NRL layers were more efficient in coverage. Compressive strength values obtained are in agreement with the spongy bones value (22–24 MPa for crossbar and 20–22 MPa for roundbar cube). Finally, the hemolytic activity of the PLA scaffold was 3%, while the scaffolds coated with 1 and 2 NRL layers presented values of 0%, indicating a potential use in biomedical applications due to the absence of hemolytic effects. [ABSTRACT FROM AUTHOR]

Recently, with the progression in wound dressings, the importance of the biocompatible material with enhanced features for potential applications in the biomedical field has been more developed. Current strategies focus on the acceleration of the wound healing by systematically designed dressing materials. In this study, biocompatible hydrogel films with the combination of silk fibroin, hyaluronic acid and gelatin biopolymers were fabricated. To gain the enhanced wound healing behavior of wound dressings, boric acid (BA) was formulated in various ratios. The prepared hydrogel films were characterized in terms of FTIR, TGA, DSC, and SEM analysis. Following to the swelling and mechanical tests, in vitro biocompatibility and wound healing tests were performed against L929 fibroblast cell line. Results suggest that the presence of 1% (wt/vol) BA in the formulation of silk fibroin/gelatin/hyaluronic acid based hydrogel films is the key in providing such an enhanced mechanical and wound healing feature and may offer an alternative approach for wound healing treatment. [ABSTRACT FROM AUTHOR]

There is a growing interest in the use of non‐polluting compounds, which come from renewable sources, and which performance in their scope is equivalent to their synthetic similes. In this work, five types of rosins from different sources were studied, verifying the existence of differences that can be inferred in their subsequent use and application as material additives. For the study, rosins were analyzed using gas‐mass chromatographic techniques, infrared spectrophotometry (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and color characterization. The results showed that the samples are composed of either abietic acid or by its structural isomers in contents higher than 80%. FTIR shows that the main difference in the gum rosins is related to the proclivity to absorb environmental moisture and that this technique is not enough to differentiate them. Moreover, the DSC reveals that the gum rosins present enthalpy relaxation effects due to their manufacturing process. The TGA showed that gum rosins are thermally stable until 200°C, therefore they can be successfully blended with thermoplastic polymers. Finally, the color characterization shows little differences between the samples, being CA the gum rosin with the greatest total color differences. [ABSTRACT FROM AUTHOR]

Polyhydroxybutyrate (PHB) is a sought‐after alternative biopolymer to synthetics with its high biodegradability and similar properties to available polymers. However, its high production cost narrows its market application. In this study, cheap, biocompatible, and widely available fillers such as cellulose (CL) and calcium carbonate (CC) were incorporated into PHB using a heat‐assisted solution casting method to reduce the manufacturing cost of the bioplastic while retaining its properties. Characterization tests found that both natural fillers have relatively low miscibility with PHB which may be accounted for by self‐ and co‐agglomeration of the fillers while having improved thermal stability. The Young's modulus of the bioplastic films increased with the introduction of CC, while the mechanical property slightly decreased upon the addition of CL attributing to the aggregation of fillers. Full biodegradation of all composites within 8 weeks was observed in the compost biodegradability tests; PHB 90 CC 10 biodegraded the slowest after the 50th day, while PHB 90 CL 10 fully disintegrated after the 30th day. Further improvements such as the incorporation of cheap, naturally derived crosslinkers or plasticizers can greatly improve the properties of the synthesized biocomposites. [ABSTRACT FROM AUTHOR]

The application of traditional cellulosic paper is limited because of its flammability, so it is necessary to explore new materials that can be used in the field of flame‐retardant paper. Based on the synergistic effect between fibers, flame‐retardant lyocell (FRL) and calcium alginate (FRL/Ca‐Alg) composite paper is prepared by a simple but efficient method. The thermal degradation process of the composite paper is analyzed by thermogravimetric (TG) and TG analysis coupled with Fourier transform infrared, the flame retardancy of the composite paper is analyzed by vertical flammability (VF) tests, limiting oxygen index test and cone calorimetry test, and the morphology of the residue after VF tests is observed by scanning electron microscopy. It is found that, the Ca‐Alg releases a large amount of CO2 before ignited, which delayed the ignited time of the composite paper; FRL reduces the effective combustion heat of composite paper during combustion, and the compact char formed by FRL effectively inhibits the smoldering of Ca‐Alg in the end stage of combustion. Based on these, the synergistic flame‐retardant effect of composite paper is proposed. [ABSTRACT FROM AUTHOR]

Thermoplastic polyurethanes (TPUs) bear tunable chemistry offering the possibility to develop a rich palette of physio‐mechanical properties, making the materials suitable for various fields of application. The great variety in TPUs properties comes from the choices of the monomers and the reaction conditions. Herein, the mechanical properties of the developed TPUs are tailored, while fine‐tuning the hard and soft segment molar ratio, as well as the reaction conditions. TPUs are synthesized from 4,4′‐methylenebis(phenyl isocyanate), poly(tetrahydrofuran), and 1,4‐butanediol, and their thermal and mechanical properties are fully characterized. The sample with the most appropriate mechanical properties that are suitable for catheter fabrication, is selected for the biomedical application. Quaternary ammonium salt is synthesized, and 0.5 mol% is incorporated in the TPU to confer antibacterial properties to the material while preserving its mechanical strength. The microbiological tests reveal the antibacterial effect of the developed materials against Staphylococcus aureus and Pseudomonas aeruginosa, as well as 80% SiHa cell viability, after 72 h of exposure, as part of the performed cytotoxicity studies. Finally, TPUs catheter prototypes fabrication is also proposed, applying an extrusion or injection molding approach for the production of biomedical devices with desirable mechanical properties. [ABSTRACT FROM AUTHOR]