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Composite materials play a crucial role in various industries, with plastic composites being particularly significant. This research specifically focuses on producing cotton fabric layers to reinforce polymeric composites. The experiment is designed in two phases. In the first stage, woven fabric is produced using roving as weft insertion instead of the conventional threads or spun yarns. This modification enhances the absorbency of the resin matrix during composite production, leading to improved properties. The second stage of the experiment involves manufacturing composite materials using different fabric structures (plain, twill, and sateen) and varying numbers of fabric layers (1, 3, and 5). This is achieved through a novel process called Vacuum Assisted Resin Transfer Molding (VARTM), which is used for fabric composites instead of the traditional laminated composites. VARTM offers advantages in terms of production efficiency and composite quality. To evaluate the physical and mechanical properties of the resulting composites, several tests are conducted. These include tensile properties testing, bending rigidity testing, measurement of composite thickness, and determination of density. The test results provide valuable insights into the performance of fabric composites under different conditions. Furthermore, the experimental results are compared with simulations conducted using the Finite Element Method (FEM) through COMSOL software. The agreement between the experimental and simulated results confirms the reliability of the proposed approach. [ABSTRACT FROM AUTHOR]

The fibers of the deep-sea sponge Euplectella aspergillum exhibit exceptional mechanical properties due to their unique layered structure at a micrometer length scale. In the present study, we utilize a correlative approach comprising of in situ tensile testing inside a scanning electron microscope (SEM) and post-failure fractography to precisely understand mechanisms through which layered architecture of fibers fracture and improves damage tolerance in tensile loading condition. The real-time observation of fibers in the present study confirms for the first time that the failure starts from the surface of fibers and proceeds to the center through successive layers. The concentric layers surrounding the central core sacrifice themselves and protect the central core through various toughening mechanisms like crack deflection, crack arrest, interface debonding, and fiber pullout. Biological materials often exhibit multiscale hierarchical structures that can be incorporated into the design of next generation of engineering materials. The fibers of deep-sea sponge E. aspergillum possess core-shell like layered architecture. Our in situ study reveals astounding strategies by which this architecture delays the fracture of the fiber. The core-shell architecture of these fibers behaves like fiber-reinforced ceramic matrix composite, where the outer shells act as a matrix and the central core acts as a fiber. The outer shells take the environmental brunt and scarify themselves to protect the central core. The precise understanding of damage evolution presented here will help to design architected materials for load-bearing applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Copyright of Tecnologia em Metalurgia, Materiais e Mineração is the property of Associacao Brasileira de Metalurgia e Materiais and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Given the ever-growing environmental concerns, repurposing natural materials is a viable approach to developing novel green materials. Thus, the use of fish scales as reinforcement in composites has great potential. This work aimed to evaluate the influence of using arapaima fish scales as reinforcement in DGEBA/TETA epoxy composites on the mechanical and thermal properties. Composite plates using 30 vol% of arapaima fish scales were analyzed through compression tests, DMA, TGA, and DSC. The compression tests of 30 vol% arapaima/epoxy composites showed a significant increase both in Young's modulus (from 710.88±98 at 0% to 1406.20±241 MPa at 30 vol% of scales) and compressive strength (from 20.80±7.14 at 0% to 68.4±11.69 MPa at 30 vol% of scales). The DMA and TGA results showed an improvement in the thermal properties of the composites as compared to the neat epoxy resin, while the DSC results demonstrated that the use of the fish scales as reinforcement did not impair the thermal stability of the resin. These results support the potential of arapaima fish scales as reinforcement in polymeric composites for flooring applications that require high compressive strength and thermal stability. [ABSTRACT FROM AUTHOR]

Young's modulus of elasticity (or stiffness, E) is an important material property for many applications of polymers and polymer-matrix composites. The common methods of measuring E are by measuring the velocity of ultrasonic pulses through the material or by resistance to flexure, but it is difficult for ultrasound to penetrate polymers that contain filler particles, and flexural measurements require large specimens that may not mimic the clinical case. Thus, it may be difficult to determine E using conventional techniques. It would be useful to have a relatively rapid technique that could be applied to small specimens, highly filled materials, and even specimens cured in situ. We suggest using a microhardness indentation technique that was originally developed for ceramic materials. We tested two unfilled rigid polymers, four resin composites, and four unfilled polymers with lesser hardness for this study. The study found that greater Vickers hardness loads yielded more consistent results than lesser loads. We developed a modified equation for E based on Knoop microhardness indentations. We concluded that laboratories may use a microhardness indenter to estimate the elastic moduli of polymers and resin composites. The results support our initial hypotheses that the slope of the equation relating the indentation parameter and the hardness/elastic modulus ratio was different for polymers and resin composites than for ceramics; however, the intercept is the same irrespective of the material tested. [Display omitted] • It is sometimes impossible to use standard methods to determine Young's modulus. • A method was developed to determine elastic modulus using microhardness indentation. • A method of calibration for indenters with various aspect ratios is provided. [ABSTRACT FROM AUTHOR]

The demand for freshwater consumption has outpaced the rapid population growth, urbanization, and industrialization. Polymer nanocomposite plays an effective role in minimizing various environmental issues, including wastewater pollution. Integrating newly generated novel nanomaterials has sparked revolutionary and advantageous innovative nanotechnologies for industrial wastewater treatment. Nanomaterials have been used to create very effective materials for environmental applications, piquing the interest of academia and business worldwide. Additionally, improvements in polymer nanocomposite materials' characteristics have opened a wide range of industrial applications. Because they enhance membrane transport properties and offer exceptional stability under various operational conditions, polymer nanocomposites play a vital role in membrane materials. As a result, nanocomposite membranes are a new class of membranes made at the nanoscale from organic and inorganic polymeric materials. They are believed to perform better than traditional membranes. The present study reviewed the synthesis of polymer-based nanocomposite membrane technologies and the implementation of the polymer-based nanocomposite membrane in wastewater treatment. Furthermore, the review concentrated on patents related to cutting-edge polymer nanocomposites utilized in environmental applications. The inquiry also examined the thermodynamics of polymer blends, specifically focusing on their material transport and solubility. Besides, the physicochemical properties of the polymer-based nanocomposite membranes and their interaction with wastewater treatment were also reviewed in the present study. [Display omitted] • Polymeric membrane modified by various nanoparticles to alter hydrophobicity and surface properties to reduce fouling. • The choice of nanoparticles is crucial in defining the performance of polymer-based nanocomposite membranes. • Typical nanofillers employed include graphene oxide, carbon nanotubes, metal oxide nanoparticles, and clay nanoparticles. • A diverse range of inorganic and organic materials are used to fabricate nanocomposite membranes for wastewater treatment. • Advanced in the properties of polymer nanocomposite materials have opened extensive potential industrial applications. [ABSTRACT FROM AUTHOR]

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For the first time, the present review critically evaluates biodegradable polymer matrix composites containing graphene-related materials (GRMs) for antibacterial applications while discussing their development, processing routes, mechanical properties, and antibacterial activity. Due to its suitable biological properties and processability, chitosan has been the most widely used biodegradable polymer for the fabrication of GRM-containing composites with antibacterial properties. The majority of biodegradable polymers (including cellulose-, gelatine-, PVA-, PCL-, and PHA-based polymers) exhibit little to no antibacterial effect alone; however, they show significant antibacterial activity (>70%) when combined with GRMs. In vitro and in vivo studies indicate that GRMs functionalization with biodegradable polymers also reduces potential GRM cytotoxicity. Overall, GRMs in biodegradable polymer matrices provide attractive antibacterial activity against a broad spectrum of bacteria (>30 different bacteria) along with improved mechanical properties over pristine polymers, where the type and the degree of improvement provided by GRMs depend on the specific matrix. For example, the addition of GRMs into chitosan, PVA, and PCL matrices increases their tensile strength by 80%, 180%, and 40%, respectively. Challenges remain in understanding the effects of processing routes and post-processing methods on the antibacterial activity and biocompatibility of biodegradable polymer/GRM composites. Given their promising properties and functionality, research on these composites is expected to further increase along with the implementation of new composite systems. These would include a wide range of applications, e.g., wound dressings, tissue engineering, drug delivery, biosensing, and photo-thermal therapy, as well as non-medical use, e.g., antibacterial food packaging, water treatment, and antibacterial fabrics. Graphene-related materials (GRMs) in polymer matrices can provide excellent antibacterial activity against a broad spectrum of bacteria together with improved mechanical properties (e.g., tensile strength and elastic modulus) over pristine polymers; thus, research efforts and applications of biodegradable polymer matrix composites containing GRMs have increased notably in the last ten years. For the first time, the present review critically evaluates biodegradable polymer matrix composites containing GRMs for antibacterial applications while discussing their development, processing routes, mechanical properties, and antibacterial activity. Future research directions for each composite system are proposed to shed light on overcoming the existing challenges in composite performance (e.g., mechanical properties, toxicity) reported in the literature. [Display omitted] [ABSTRACT FROM AUTHOR]

The present study explores the possibilities of reinforcing High-Density Poly Ethylene (HDPE) + Nano-Clay (NC) composite with locally available inexpensive plane woven bi-directional Silk Fibre (SF) fabric for developing a new tribo material. HDPE, NC & SF were incorporated into produce hybrid laminated composites using a hot compression technique. Further, the additions of NC to bi-directional SF-based HDPE composites at five levels in the range 0.1–1.0 wt-% have improved the tribological characteristics greatly compared to HDPE + SF samples as well as pure HDPE. The experimental results indicate that SF and NC improved the wear behaviour of neat polymer. The CoF of HDPE + SF + 0.1NC over HDPE + SF & pure HDPE decreased by 15% and 30%, respectively. The results reveal that the wear loss of HDPE + SF + 0.1NC is very much lower over HDPE + SF & pure HDPE and they are about 24% and 30%, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Quartz-Fibre-Reinforced cyanate ester Plastics (QFRP) has superior performance in terms of mechanical, electromagnetic properties and are being widely used in military applications. Drilling is the general machining process for making hole to join the composite part to another sub-assembly. This study presents an influence of optimized drilling parameters on carbide tool wear and its impact on hole characteristics in QFRP composite. The aim is to achieve the optimum use of drill during the drilling process from application perspective without compromising the quality. In addition, the effect of tool wear and its impact on residual tensile strength of quartz composite are studied. The dominant wear mechanism observed is flank wear caused by the abrasive nature of the quartz fibre. The tool wear and delamination factor after drilling 200 holes are 186 μm and 1.40 respectively. The residual strength is affected by the tool wear due to relatively poor interlaminar property between fiber and resin in this quartz composite. The residual strength of quartz specimen drilled with the tool after drilling 200 holes is 14 % lower than the property of specimen drilled with fresh drill. The highlight of the present work is a combined analysis of wear in the tool, delamination induced and residual strength of quartz specimen. The results of this study strengthen the understanding of the drilling process of quartz polymeric composite material in aerospace applications. [ABSTRACT FROM AUTHOR]

Oil palm shell (OPS), one of the most abundantly produced solid bio-wastes in Southeast Asia, is yielded by crushing the oil palm kernel during palm oil extraction in the palm oil mills. Approaches have been devoted to developing the use of OPS as reinforcing filler in polymer composites to enhance the functional properties of composites. For OPS to be effective for reinforcing materials, its role and beneficial effects on the improvement of composites' properties need to be investigated. However, not many studies have discussed the potentials of incorporating OPS in thermoplastic and thermoset polymer composite applications. This paper summarises the enhancement of composite characteristics, including physical, mechanical, thermal, water barrier and biodegradability properties. Properties of OPS that make it a good candidate as a reinforcing filler, such as tensile strength, impact strength, elongation, Young's modulus, morphological and water absorption, are discussed in detail. In addition, the application of its derivative, challenges, and outlook are also discussed. [ABSTRACT FROM AUTHOR]

Polymeric composites are widely used in aerospace. One such important use of polymeric composites is the filament-wound composite case for the Solid Rocket Motor (SRM). Environmental conditions expected during flight and other phases of the SRMs life cycle affect its performance. The performance of SRM, in turn, depends primarily on the composite case and propellant grain. In this study, the performance evaluation of SRM with the composite case is carried out for different environmental conditions. These cases are designed to sustain very high pressure and temperature environments generated due to the combustion of propellant grains and are intended to perform adequately at any time during their service life. The performance evaluation test matrix is formulated considering various expected dynamic and thermal conditions. The small SRM with a composite case is subjected to planned tests as per the matrix, followed by static tests. The pressure versus time data is plotted for all test conditions. The ballistic parameters result of the virgin (without subjecting it to any test) small SRM is considered as a reference for comparative studies with the rest of all other test conditions results. All the ballistic performance test results are also analysed with respect to the pressure-time curve for mission bounds. The analysis of experimental test results reveals that various environmental dynamic conditions like random vibration, acceleration and shock, do not affect the composite case and the ballistic performance of a small SRM. The effect of grain temperature on ballistic performance is also found as expected. [ABSTRACT FROM AUTHOR]

Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The utility of functional hydrocolloids have envisaged new formulations and combination of biopolymers and their functionalization in nutraceutical industry. The study have examined chitosan sodium benzoate complex based hydrocolloid interacts with GI proteins. The interaction of polymers have been analysed with a Insilco approach where itaids in exploring the polymeric composites interact with gastric juice proteins and intestinal wall proteins. The interaction was found in the proteins like Taste receptor type 1 member 3, Adenylate cyclase type 1, Anion exchange transporter showed best docking scores against each ligand compound like chitosan, sodium benzoate and chitosan sodium benzoate composite. The overall interaction of these composites and gastric proteins could render new information for polymer protein interaction specifically to hydrocolloids that could be used for pharma and healthcare industry. [ABSTRACT FROM AUTHOR]

The article examines the ways to solve the problem of developing a scientific basis for obtaining composite materials of different functional purposes from oilseed flax fibers. Composite materials came to the forefront of production and demand for goods several decades ago, thanks to unsurpassed specific and mechanical properties as a result of growing consumer and industry demand for high-tech materials and structures. However, the combination of natural fibers with a polymeric material or matrix increases the difficulty of the process of forming composites and, as a rule, leads to problems in the physicochemical processes of interaction of the matrix and the filler. Composites with synthetic filters have obvious advantages, but their disposal is difficult, requires the development of environmental processing technologies. The best way to save the environment when processing composite materials is to use nontoxic natural materials for their production, but this requires the development of innovative technologies for forming composite materials with natural fibrous fillers. The paper covers theoretical and experimental research in the area of processing flax raw materials. The purpose of the study is to provide scientific substantiation of developing the technologies for obtaining fillers to reinforce composite materials. In order to do it, we performed modification of oilseed flax fiber and developed technologies for processing oilseed flax straw with regulated technological and performance characteristics. The article also presents the results of the research on determining causes of low wettability of oilseed flax bast. In order to find out the causes of low bast wettability, we conducted research on examining chemical composition and anatomy of straw stems. The formulation for preparing the fiber aimed to be used as filler for reinforcement of composite materials is offered. The study suggests evaluation of the quality of composite materials produced on the basis of using modified oilseed flax fibers. [ABSTRACT FROM AUTHOR]

PLLA-magnesium composites have been widely investigated as potential biodegradable materials for bone implants. Lower/higher corrosion resistance of the crystalized/amorphous magnesium alloys allows tailoring of biodegradability rate. In this work, the amorphous Mg 65 Zn 30 Ca 5 was investigated versus traditional crystalized Mg 65 Zn 30 Ca 5 , and a PLLA-Mg 65 Zn 30 Ca 5 composite has been successfully fabricated using hot injection process. Furthermore, the high corrosion resistance of the amorphous Mg 65 Zn 30 Ca 5 prevented the high alkalization and deterioration of mechanical strength. In addition, the high Zn content intended to improve the glass forming ability, also enhances the anti-bacterial property of the PLLA-Mg 65 Zn 30 Ca 5 composite. The remarkable performance of the PLLA-Mg 65 Zn 30 Ca 5 composite shows its promising application in bone repair and tissue regeneration. [ABSTRACT FROM AUTHOR]

Copyright of Science of Sintering is the property of National Library of Serbia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Most fractures heal by a combination of endochondral and intramembranous ossification dependent upon strain and vascularity at the fracture site. Many biomaterials-based bone regeneration strategies rely on the use of calcium phosphates such as nano-crystalline hydroxyapatite (nHA) to create bone-like scaffolds. In this study, nHA was dispersed in reactive polymers to form composite scaffolds that were evaluated both in vitro and in vivo. Matrix assays, immunofluorescent staining, and Western blots demonstrated that nHA influenced mineralization and subsequent osteogenesis in a dose-dependent manner in vitro. Furthermore, nHA dispersed in polymeric composites promoted osteogenesis by a similar mechanism as particulated nHA. Scaffolds were implanted into a 2-mm defect in the femoral diaphysis or metaphysis of Sprague-Dawley rats to evaluate new bone formation at 4 and 8 weeks. Two formulations were tested: a poly(thioketal urethane) scaffold without nHA (PTKUR) and a PTKUR scaffold augmented with 22 wt% nHA (22nHA). The scaffolds supported new bone formation in both anatomic sites. In the metaphysis, augmentation of scaffolds with nHA promoted an intramembranous healing response. Within the diaphysis, nHA inhibited endochondral ossification. Immunohistochemistry was performed on cryo-sections of the bone/scaffold interface in which CD146, CD31, Endomucin, CD68, and Myeloperoxidase were evaluated. No significant differences in the infiltrating cell populations were observed. These findings suggest that nHA dispersed in polymeric composites induces osteogenic differentiation of adherent endogenous cells, which has skeletal site-specific effects on fracture healing. Understanding the mechanism by which synthetic scaffolds promote new bone formation in preclinical models is crucial for bone regeneration applications in the clinic where complex fracture cases are seen. In this study, we found that dispersion of nHA in polymeric scaffolds promoted in vitro osteogenesis in a dose-dependent manner through activation of the PiT1 receptor and subsequent downstream Erk1/2 signaling. While augmentation of polymeric scaffolds with nHA enhanced intramembranous ossification in metaphyseal defects, it inhibited endochondral ossification in diaphyseal defects. Thus, our findings provide new insights into designing synthetic bone grafts that complement the skeletal site-specific fracture healing response. [Display omitted] [ABSTRACT FROM AUTHOR]

One of the most significant environmental problems facing the entire planet today is water contamination, which is caused by the increasing industry and urbanization. The present study involves the synthesis of polymeric ferrite composites Ni-CoFe 2 O 4 /Chitosan, Zn-NiFe 2 O 4 /Starch, Co-NiZnFe 2 O 4 /Polyaniline, Ni doped CrZnFe 2 O 4 /Alginate, and Cr doped ZnCoFe 2 O 4 /PVA for the removal of Golden Yellow-160 dye. The polymeric ferrite composites were characterized using Scanning electron microscopy (SEM), X-ray Diffraction (XRD), and Fourier transmission infrared spectroscopy (FT-IR) which showed the surface morphology, crystallinity, chemical structure and thermal stability of the composites. To get the optimal removal, different parameters like pH, composite dose, contact time, temperature and initial dye concentration were optimized. Different equilibrium and kinetic models were used to check the nature of process and reaction rate of sorption. Thermodynamic were studied to check the feasibility of reaction. The effect of presence of various electrolytes NaCl, CaCl 2.2 H 2 O and AlCl 3.6 H 2 O was also studied. Effect of presence of different metals and surfactants was also studied which cause reduction in adsorption of dyes. For large scale, the effects of bed height, flow rate, and initial dye concentration were examined in column study. Different eluents were used for the desorption study of reactive dyes to check the reusability of process. [Display omitted] • Langmuir adsorption isotherm displayed chemisorption nature of adsorption. • Both pseudo-first-order and pseudo-second-order showed the satisfactorily fitness. • Zn-NiFe 2 O 4 /Starch showed the highest removal among all the composites. • The dye exclusion showed the endothermic nature of reaction. • The current study applied for the removal of dye at large scale using a column. [ABSTRACT FROM AUTHOR]

It is of great importance to meet the need for clean and usable water in the world, which is one of the main priority issues of the European Foresight Platform action plan, and to improve and develop existing technologies in this regard. Membrane technology is one of the most used technologies in water treatment, which can be easily and economically modernized. In this study, we aimed to eliminate some disadvantages that affect the performance and cost of membranes, such as physical/chemical stability and contamination of the surface, by incorporating cyclodextrin derivatives (x-CDs, x: α,β,γ) functionalized reduced graphene oxide (rGO). Membrane performance studies such as contamination tests using water permeability, bovine serum albumin (BSA), flux, and arsenic (As) removal in the table-top pilot system were examined and compared for each composite membrane prepared at different rates. The results showed that the salt rejection values were ranked as Na 2 SO 4 > NaCl> MgSO 4 > MgCl 2 according to the salt type and it increased depending on the amount of substance. Besides, the arsenate removal studies were performed with the prepared membranes and it was observed that a maximum of 87.6% of the As was removed from the groundwater sample obtained from the Emet (Kütahya/Turkey) district. • New generation nanoporous polymeric composite membranes were prepared. • Cyclodextrins-functionalized reduced graphene oxide was incorporated into membranes. • The performance studies of membranes were examined in the table-top pilot system. • The salt rejection values were ranked as Na 2 SO 4 > NaCl > MgSO 4 > MgCl 2. • A maximum of 87.6% arsenate was removed from the groundwater sample. [ABSTRACT FROM AUTHOR]

The aim of the present work is fabrication of dual cross linked sodium alginate (SA)/montmorillonite (MMT) microbeads as a potential drug vehicle for extended release of curcumin (CUR). The microbeads were prepared using in situ ion-exchange followed by simple ionotropic gelation technique. The developed beads were characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (X-RD) and scanning electron microscopy (SEM). The effect of MMT on encapsulation efficiency of CUR and intercalation kinetics was investigated. Dynamic swelling study and in vitro release study were investigated in simulated intestinal fluid (pH 7.4) and simulated gastric fluid (pH 1.2) at 37 °C. Results suggested that both the swelling and in vitro release studies were influenced by the pH of test media, which might be suitable for intestinal drug delivery. The release mechanism was analyzed by fitting the release data into Korsmeyer-Peppas equation. [Display omitted] • The microbeads prepared using sodium alginate (SA)/montmorillonite (MMT) were found to be potentially good carriers of curcumin (CUR) for extended release of CUR. • The bioavailability of CUR is increased by the usage of MMT in the microbeads, hence making it possible to enhance the anti-tumour activity. • The incorporation of multivalent ions like Mg2+, Ba2+ and Al3+ into calcium alginate matrix modified the swelling property and release rate of bio-active molecules. • The porous nature of the microbeads was based on the size and interaction of the ions namely Mg2+, Ba2+ and Al3+ with alginate. [ABSTRACT FROM AUTHOR]

In many biogenic materials, chitin chains are assembled in fibrils that are wrapped by a protein fold. In them, the mechanical properties are supposed to be related to intra- and inter- interactions among chitin and proteins. This hypothesis has been poorly investigated. Here, this research theme is studied using the pen of Loligo vulgaris as a model material of chitin-protein composites. Chemical treatments were used to change the interactions involving only the proteic phase, through unfolding and/or degradation processes. Successively, structural and mechanical parameters were examined using spectroscopy, microscopy, X-ray diffractometry, and tensile tests. The data analysis showed that chemical treatments did not modify the structure of the chitin matrix. This allowed to derive from the mechanical test analysis the following conclusions: (i) the maximum stress (σ max) relies on the presence of the disulfide bonds; (ii) the Young's modulus (E) relies on the overall correct folding of the proteins; (iii) the whole removal of proteins induces a decrease of E (> 90%) and σ max (> 80%), and an increase in the maximum elongation. These observations indicate that in the chitin matrix the proteins act as a strengthener, which efficacy is controlled by the presence of disulfide bridges. This reinforcement links the chitin fibrils avoiding them to slide one on the other and maximizing their resistance and stiffness. In conclusion, this knowledge can explain the physio-chemical properties of other biogenic polymeric composites and inspire the design of new materials. To date, no study has addressed on how proteins influence chitin-composite material's mechanical properties. Here we show that the Young's modulus and the maximum stress mainly rely on protein disulfide bonds, the inter-proteins ones and those controlling the folding of chitin-binding domains. The removal of protein matrix induce a reduction of Young's modulus and maximum stress, leaving the chitin matrix structurally unaltered. The measure of the maximum elongation shows that the chitin fibrils slide on each other only after removing the protein matrix. In conclusion, this research shows that the proteins act as a stiff matrix reinforced by di-sulfide bridges that link crystalline chitin fibrils avoiding them to slide one on the other. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The recent advances in wearable electronics and intelligent human-machine interface systems have garnered great interests in electromechanical sensors, which can measure and quantify physical stimuli. Among different types of electromechanical sensors, piezoresistive sensors have been extensively investigated due to the excellent sensitivity, simple construction, and durability. Especially, there have been remarkable developments of flexible and stretchable piezoresistive sensors for wearable devices by investigating novel material/structural strategies to obtain highly sensitive piezoresistive sensors with skin-like flexibility. Here, we give a comprehensive overview of the recent progress in flexible and stretchable piezoresistive sensors and their applications. Based on the material composition and structural characteristics, the piezoresistive sensors are categorized into three types— conductive polymeric composite, porous conductive material, and architected conductive material. Subsequently, we have summarized their transduction mechanisms, fabrication processes, sensing performances, and applications. Finally, we have discussed current challenges and future opportunities for piezoresistive sensors. [ABSTRACT FROM AUTHOR]

Solid-state milling is a promising ecologically friendly method for fabricating polymeric blend and composite powder raw materials for several subsequent manufacturing processes. Biodegradable polymers, blends, and composites are expected to find extensive use by industry due to their environmental friendliness and acceptable mechanical and thermal properties for several applications. Poly-ε-caprolactone (PCL), poly-ethylene-oxide (PEO), and their blends have attracted so much attention to replace commodity polymers in future applications. Therefore, in the current research, bulk compounding of PCL-PEO blends with various compositions using solid-state cryomilling was investigated. Structural, mechanical, thermal, and hydrophilicity properties were examined on samples obtained by compression molding to explore the capabilities of the milling process for various applications. Morphology of the blends was explored by scanning electron microscopy (SEM), which showed a clear phase separation in blends after heating. Dispersed as well as co-continuous morphologies were achieved by varying composition. Differential scanning calorimetry (DSC) and x-ray diffraction (XRD) of the blends indicated insignificant amorphization by milling. Tensile strength, modulus, and percentage elongation at break of the blends demonstrated significant variations due to processing parameters. Image 1 • Cryomilling is a green, cheap, simple and effective route to produce blend powders. • Cryomilling provides adequate compounding despite immiscibility of components. • PCL/PEO blend powders with different compositions were fabricated via cryomilling. • Blend mechanical properties were modulated through varying blend composition. • Blend morphologies were modified through manipulating processing parameters. [ABSTRACT FROM AUTHOR]

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract The aim of this work was to develop, optimize and characterize a silymarin-laden polyvinylpyrrolidone (PVP)-polyethylene glycol (PEG) polymeric composite to resolve low aqueous solubility and dissolution rate problem of the drug. A number of silymarin-laden polymeric formulations were fabricated with different quantities of PVP K-30 and PEG 6000 by the solvent-evaporation method. The effect of PVP K-30 and PEG 6000 on the aqueous solubility and dissolution rate was investigated. The optimized formulation and its constituents were characterized using powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) techniques. Both the PEG 6000 and PVP K-30 positively affected the aqueous solubility and dissolution rate of the drug. In particular, a formulation consisting of silymarin, PVP K-30 and PEG 6000 (0.25/1.5/1.5, w/w/w) furnished the highest solubility (24.39±2.95 mg/mL) and an excellent dissolution profile (~100% in 40 min). The solubility enhancement with this formulation was ~1150-fold as compared to plain silymarin powder. Moreover, all the constituents existed in the amorphous state in this silymarin-laden PVP-PEG polymeric composite. Accordingly, this formulation might be a promising tool to administer silymarin with an enhanced effect via the oral route. Graphical abstract fx1 [ABSTRACT FROM AUTHOR]

Abstract Possibility of using Delonix regia (Dr) seed particles as reinforcement for production of new polymeric composites has been studied. Dried Dr seeds were processed using a disc grinder and then classified. Dr particles of 105 μm average size were incorporated into recycled low density polyethylene (RLDPE) up to 10 wt% and RLDPE/ Dr particle composites were produced through compounding and compressive moulding technique. Effects of Dr particle addition on morphology and the tensile properties of the produced composites were investigated. The composite tensile properties were confirmed and validated using mono-variate regression model involving full factorial design of one factor-five levels. Results obtained indicated presence of void within the composite grain which impair the tensile strength and strain of the RLDPE composite at 10 wt% of Dr seed particle addition. About 300% and 41% maximum increments in tensile strength and strain were noticed at 4 wt%. The developed models show that wt% of Dr particles has significantly statistical influences on both tensile strength (P = 0.00827) and strain (P = 0.01756). About 93% and 89% response prediction by the models shows that the models exhibit fit goodness and they are appropriate for confirmation of experimental tensile properties. Therefore, this study has given birth to a new polymeric composite for engineering applications. [ABSTRACT FROM AUTHOR]

Abstract Nanomaterials, such as ZrO 2 nanoparticles (ZrO 2 NPs), are very effective in water remediation. However, the safety issues related to nanoparticle release and toxicity to humans remain to be resolved. Here we evaluated the cytotoxicity of ZrO 2 NPs and their adducts with pollutants using a human cell panel containing stomach, intestine, liver and kidney cells. We found that different pollutants or ZrO 2 NP/pollutant adducts targeted cells from different organs, suggesting the necessity of a cell panel to model oral exposures. The cooperation of ZrO 2 NPs and pollutants was quite complex, consisting of synergistic, antagonistic, or additive effects. For example, ZrO 2 NPs enhanced the cytotoxicity of Pb2+ in GES-1 cells and of Pb2+, Cd2+ in FHC cells, while alleviating the toxicity of Pb2+ and As (III) in HepG2 and Hek293 cells. Our results also indicated that even concentrations of pollutants that meet the national standard, the ZrO 2 NPs concentration should be kept below 17 μg/mL to avoid ZrO 2 NP/pollutant adduct synergistic toxicity. Graphical abstract fx1 Highlights • Wastewater remediation using Polymer/ZrO 2 NP composite releases ZrO 2 nanoparticles. • Human cell panel modeling oral exposure is superior to single cell model. • Human cells from different organs show different toxicity to pollutants and nanoaprticles. • ZrO 2 NPs exhibit synergistic or antagonistic effects with different pollutants. [ABSTRACT FROM AUTHOR]

Abstract A doum palm particulate reinforced polyvinyl chloride (PVC) composite was developed with considerably low cost materials providing an overall light-weight and good mechanical properties for potential application as piping material. The specimen composite material was produced with the doum palm (leaves) particulate as reinforcement using compression molding. Results showed that density and elastic Modulus of the composite decreases and increases respectively with increasing weight fraction of the particulate reinforcement. The tensile strength increased to a maximum of 50 MPa and then decreased steadily. The composition with optimum mechanical property (50 MPa) was determined at 8, 62 and 30% formulation of doum palm particulates (reinforcement), PVC (matrix) and Kankara clay (filler) respectively with corresponding percentage water absorption of 0.72%, Young's Modulus of 2 GPa, flexural strength of 84 MPa and density of 1.43 g/cm3. Fourier Transform Infrared (FTIR) analysis of the constituents showed identical bands within the range 4000–1000 cm−1 with renown research work. Scanning Electron Microscopy (SEM) result showed fairly uniform distribution of constituents' phases. X-Ray Fluorescence (XRF) confirms the X-ray diffraction (XRD) result of the presence of minerals of kaolinite, quartz, rutile and illite in the kaolin clay. Comparison with conventional piping materials showed the composite offered a price savings per meter length of 86.6% and 35.9% when compared with carbon steel and PVC material. [ABSTRACT FROM AUTHOR]

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this laboratory study was to evaluate the monomer leaching and degree of conversion (DC) from experimental bioactive resin composites (RBCs) and to do comparison with commercial bulkfill and packable resin composites. Experimental dimethacrylatebased resin composites were reinforced with silanated nano-hydroxyapatite (30 and 45 wt%). The ion leaching and DC of these resin composites were compared and contrasted with SDR? and Filtek P60? by using the high performance liquid chromatography (HPLC) and Fourier transform infrared spectroscopy (FTIR), respectively. A significant difference was found in elution of monomer between the resin composites. SDR? showed significantly high monomer elution and structural changes compared to other resin composites. The DC of bioactive RBCs showed the highest conversion rate after polymerization. Resin composite with nano-hydroxyapatite with the presence of a bioactive component might provide biomimetic approach for the material. Moreover, a low concentration of nanohydroxyapatite nano-fillers have shown better properties than micro-fillers based resin composites. [ABSTRACT FROM AUTHOR]