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Abstract\nHIGHLIGHTSThe current impetus to develop bio-based polymers for greater sustainability and lower carbon footprint is necessitated due to the alarming depletion of fossil resources, concurrent global warming, and related environmental issues. This article reviews the development of polymeric blends based on bio-based polymers. The focus on bio-based polymers is due to their greater ‘Sustainability factor’ as they are derived from renewable resources. The article delves into the synthesis of both conventional and highly biodegradable bio-based polymers, each crafted from feedstocks derived from nature’s bounty. What sets this work apart is the exploration of blending existing bio-based polymers, culminating in the birth of entirely new materials. This review provides a comprehensive overview of the recent advancements in the development of bio-based polymeric blends, covering their synthesis, properties, applications, and potential contributions to a more sustainable future. Despite their potential benefits, bio-based materials face obstacles such as miscibility, processability issues and disparities in physical properties compared to conventional counterparts. The paper also discusses significance of compatibilizers, additives and future directions for the further advancement of these bio-based blends. While bio-based polymer blends hold promise for environmentally benign applications, many are still in the research phase. Ongoing research and technological innovations are driving the evolution of these blends as viable alternatives, but continued efforts are needed to ensure their successful integration into mainstream industrial practices. Concerted efforts from both researchers and industry stakeholders are essential to realize the full potential of bio-based polymers and accelerate their adoption on a global scale.Sustainable versatility: Reduce fossil fuel dependency and decompose naturally.Challenges: Poor mechanical properties and scalability.Modification strategies: Blending improves properties for specific uses.Market potential: Good market potential, despite a commercialized gap.Research need: To address challenges and advance bio-based polymer technology [ABSTRACT FROM AUTHOR]

Natural lipids with nutritional or therapeutic benefits that also provide desired texture, melting and organoleptic appeal (mouthfeel, skin feel) are difficult to procure for the food and cosmetics industries. Natural Astrocaryum pulp oil (AVP) and kernel fat (AVK) from Guyana were blended without further modification to study the potential of extending the physical functionality of the blends beyond that of crude AVK and AVP. An evaluation of non-lipid components by ESI-MS indicated twenty-four (24) bioactive molecules, mainly carotenoids (90%), polyphenols (9%) and sterols (1%) in AVP, indicating important health and therapeutic benefits. Only trace-to-negligible amounts of these compounds were detected in AVK. The thermal transition phase behavior, solid fat content (SFC), microstructure and textural properties of five AVP/AVL blends were used to construct phase diagrams of the AVK/AVP binary system. Binary phase diagrams constructed from the cooling and heating DSC thermograms of the mixtures and description of the liquidus line indicated a mixing behavior close to ideal with a tendency for order, with no phase separation. Melting onsets, solid fat content and measurements of solid-like texture all predictively increased with increasing AVK content. The descriptive decay parameters obtained for SFC, crystal size, hardness, firmness and spreadability were similar and predictive and indicate the way the binary system structure approaches that of a liquid or a functional solid. The bioactive content of the blends was accurately calculated; the work provides a blueprint for the blending of AVP and AVK to deliver targeted bioactive content, stability, spreadability, texture, melting profile, organoleptic appeal and solid content. SFCs at 20 °C ranged from 9.1% to 39.1%, melting onset from −17.5 °C to 27.8 °C, hardness from 0.1 N to 3.5 N and spreadability from 3.3 N·s to 147.1 N·s; indicating a useful dynamic range of physical properties suitable for bioactive oils to bioactive butters. [ABSTRACT FROM AUTHOR]

Currently, Polyhydroxyalkanoates (PHAs) especially Polyhydroxybutyrate (PHB) have gained much attention as an environmentally benign alternative to petroleum-derived plastics. However, path to a bright future of sustainable production and development has been hampered by their dubious quality. PHAs are biodegradable, biocompatible, and non-toxic which make them excellent choices for packaging, agriculture, and medicine. Despite having such great scope, PHAs have a number of disadvantages, including a high cost, brittleness, thermal instability, and poor mechanical properties. Thus, PHAs need to be upgraded to enhance its inherent qualities. This upgradation can be primarily achieved by blending PHAs either with natural or synthetic bio-based polymers and adding reinforcements to develop novel PHAs-based biocomposites and blends. Keeping the view of future PHAs multi-dimensional applications, the present study provides an extensive understanding of the blending of PHAs to enhance their physico-chemical traits. Additionally, a number of state-of-the-art processing methods are also discussed in the present study. [ABSTRACT FROM AUTHOR]

The objective of the present study was to increase the frying stability of refined safflower oil (RSO) by blending it with refined olive pomace oil (ROPO) during deep fat frying. For this purpose; RSO, ROPO and their blends were utilized for frying of potato sticks at 180°C for 3 consecutive days. The frying stability of the oils was monitored by analyzing them for their free fatty acids, peroxide values, total polar contents, ultraviolet spectrophotometric indices at 232 and 270 nm, fatty acid profiles, p-anisidine values, α- tocopherol contents and photometric color indices. 3-monochloropropane-1,2-diol (3-MCPD) and glycidyl ester (GE) levels of oils before and after frying were measured as well. The results have shown that thermooxidative degradation products increased as the frying progressed for all oils, however the decomposition rate was found to slow down in blend oils by stabilizing with ROPO. Blending RSO with ROPO decreased linoleic and linolenic; but increased the oleic and palmitic acid percentages of the blends. C18:2/C16:0 ratio was found to decrease by frying for RSO and the blend oils, however ROPO was not affected significantly. 3-MCPD-E levels of the blends increased as the ratio of ROPO increased. Principal component analysis enabled a clear discrimination between oils with different composition throughout the frying process. [ABSTRACT FROM AUTHOR]

Twelve crude oil blends prepared from seven individual crude oils and an imported atmospheric residue were characterized through a true boiling point (TBP) distillation analysis and their density. When comparing the measured TBP fraction yields with those estimated through the application of the additive blending rule, it was found that, for four crude oil blends, the additive blending rule was valid, while for the remaining eight crude oil blends, deviations of the measured TBP yields from the estimated ones were bigger than the TBP analysis's repeatability limits. By the use of intercriteria analysis evaluation of the data for the deviation of the TBP yields from the additive blending rule and the molar excess volume of the crude oil blends, statistically meaningful relations between the delta TBP yields of light and heavy naphtha, as well as vacuum residue with the molar excess volume, were found. The higher the magnitude of the crude oil blend's molar excess volume, the bigger the deviations of the TBP yields of naphtha and vacuum residue are. The bigger the deviation of the crude oil blend's behavior from that of the regular solution, as quantified by the molar excess volume, the bigger the deviations of the TBP yields of naphtha and vacuum residue are. [ABSTRACT FROM AUTHOR]

The production of heavy fuel oil from hydrocracked vacuum residue requires dilution of the residue with cutter stocks to reduce viscosity. The hydrocracked residue obtained from different vacuum residue blends originating from diverse crude oils may have divergent properties and interact with the variant cutter stocks in a dissimilar way leading to changeable values of density, sediment content, and viscosity of the obtained fuel oil. H-Oil hydrocracked vacuum residues (VTBs) obtained from different crude blends (Urals, Siberian Light (LSCO), and Basrah Heavy) were diluted with the high aromatic fluid catalytic cracking (FCC) light cycle, heavy cycle, and slurry oil, and the low aromatic fluid catalytic cracking feed hydrotreater diesel cutter stocks and their densities, sediment content, and viscosity of the mixtures were investigated. Intercriteria analysis evaluation of the data generated in this study was performed. It was found that the densities of the blends H-Oil VTB/cutter stocks deviate from the regular solution behavior because of the presence of attractive and repulsive forces between the molecules of the H-Oil VTB and the cutter stocks. Urals and Basrah Heavy crude oils were found to enhance the attractive forces, while the LSCO increases the repulsive forces between the molecules of H-Oil VTBs and those of the FCC gas oils. The viscosity of the H-Oil VTB obtained during hydrocracking of straight run vacuum residue blend was established to linearly depend on the viscosity of the H-Oil vacuum residue feed blend. The applied equations to predict viscosity of blends containing straight run and hydrocracked vacuum residues and cutter stocks proved their good prediction ability with an average relative absolute deviation (%AAD) of 8.8%. While the viscosity was found possible to predict, the sediment content of the blends H-Oil VTBs/cutter stocks was recalcitrant to forecast. [ABSTRACT FROM AUTHOR]

Presently, society needs an eco-friendlier alternative for non-biodegradable polymers, nonetheless, synthetic polymers have established the market because of cost and easy to manufacture. To address the challenge of reducing the lifetime of degradation of these polymers, the scope of blending natural biopolymers is effective. This paper focuses on confirming the effectiveness of biodegradation in the molecular level of polymer blends between synthetic polymers and biopolymers. The synthetic polymers such as poly (methyl methacrylate) (PMMA) and poly (vinyl chloride) (PVC) were blended with varying compositions of biodegradable cellulose acetate butyrate (CAB). Using dimethylformamide (DMF) the films of PMMA/CAB, PVC/CAB blends were prepared by the solution casting method. Four different methods for studying biodegradability of these blends, namely soil burial test, enzymatic degradation, activated sludge degradation followed by microbial degradation were performed. The confirmation of degradation was done by NMR, FTIR, and Gel Permeation Chromatography (GPC) studies. Moreover, degradation analyses were determined by the weight loss method. Sufficient biodegradability was shown with an increase in CAB content in the blend. This work provides an approach for bringing about the degradation of synthetic polymers without much compromise on their properties. Also, the type of microorganisms that effectively degrades these polymer bends can be known. [ABSTRACT FROM AUTHOR]

To obtain industrialized poly(ethylene terephthalate) (PET) composites with highly efficient flame retardancy, a phosphorus-nitrogen (P-N) containing hyperbranched flame retardant additive was synthesized by 9,10-dihydro-9-oxa-10-phospho-phenanthrene-butyric acid (DDP) and tris(2-hydroxyethyl) isocyanurate (THEIC) through high temperature esterification known as hyperbranched DDP-THEIC (hbDT). The chemical structure of the synthesized hbDT was determined by FTIR, 1H NMR, 13C NMR, and GPC, etc. Subsequently, hbDT/PET composites were prepared by co-blending, and the effects of hbDT on the thermal stability, flame retardancy, combustion performance, and thermal degradation behavior of PET were explored to deeply analyze its flame retardant mechanism. The test results showed that hbDT was successfully synthesized, and that hbDT maintained thermal stability well with the required processing conditions of PET as retardant additives. The flame retardant efficiency of PET was clearly improved by the addition of hbDT via the synergistic flame-retardant effect of P and N elements. When the mass fraction of flame retardant was 5%, the LOI of the hbDT/PET composite increased to 30.2%, and the vertical combustion grade reached UL-94 V-0. Compared with pure PET, great decreased total heat release (decreased by 16.3%) and peak heat release rate (decreased by 54.9%) were exhibited. Finally, the flame retardant mechanism of hbDT/PET was supposed, and it was confirmed that retardant effect happened in both the gas phase and condensed phase. This study is expected to provide a new idea for the development of low toxic, environment-friendly and highly efficient flame retardant additive for polyesters in an industry scale. [ABSTRACT FROM AUTHOR]

Ethylene acrylic acid copolymer (EAA) is widely used as tie-layer in multilayer film structures containing aluminum foil. EAA provides adhesion between the foil and rest of the film structure. It can be used alone or as a blend with low density polyethylene (LDPE), ordinarily between 20 and 50%. However, blending EAA and LDPE does not always produce desirable results. From time to time, a clear film becomes hazy as the EAA content is increased. At the same time, the adhesive strength to foil decreases. This study focuses on elucidating the mechanism behind the high haze and poor adhesion associated with EAA/LDPE blends and on determining factors that can optimize blend performance. The results from this study indicate that immiscibility, not viscosity mismatch, is the dominant factor affecting EAA/LDPE blends. In general, EAA with low acid content is more compatible with LDPE than EAA with high acid content. Processing parameters, such as extruder RPM and melt temperature, can also be selectively used to improve the blend haze or layer adhesion. [ABSTRACT FROM AUTHOR]

PBT and PET are subjected to thermal-oxidative degradation and thermomechanical degradation during the process of melt blending, which affect the polymer structure and properties. The effect of feed properties of PET and the addition of modified nanoparticles on blends are a question worthy of discussion. This work describes the melting and thermal stability, the crystallization behavior and non-isothermal crystallization kinetic, the rheological behaviors and mechanical properties of several PBT/PET blends prepared by twin-screw melt extrusion. Results show that the molecular chain of the polyester blends obtained by stable extrusion are not significantly degraded, there is only one obvious melting peak and crystallization peak on the thermal analysis curves, and the melting point is lower than either of the two polyesters. An appropriate amount of SD can effectively reduce the crystallization rate of the PBT material and extend the crystallization time. The rheological behavior of PBT/PET blends is complicated than PET raw materials and SD, as well as the melt processing temperature and shear rate will all affect the rheological behavior of the blends. For example, at low shear rate, polyester blends with SD exhibit strong shear thinning behavior. In general, the SD content affects the rheological property of blends in a way similar to the law of influence on crystallization behavior. When SD content is 0.3 wt%, a polyester product with higher elongation at break than pure PBT can be obtained. This can provide a useful reference for preparing commercialized polyester blend products with good melt processability and elongation by simple blending. [ABSTRACT FROM AUTHOR]

An approach on the reactive processing and compatibilization of plastic waste was simulated for the mixture of thermoplastics with the major content in municipal plastic waste: low‐density polyethylene, high‐density polyethylene, polypropylene, polystyrene, poly(vinyl chloride) (PVC), polyethylene terephthalate, polymethyl methacrylate, PA6, and acrylonitrile‐butadiene‐styrene. Peroxide initiators 2,5‐bis(tert‐butylperoxy)‐2,5‐dimethylhexane (L101) and hydrogen peroxide (H2O2) and poly(styrene‐b‐ethylene‐b‐butylene‐b‐styrene) grafted with maleic anhydride (SEBS‐g‐MAH) were used for the reactive processing of polymer blend under optimized conditions (concentration, reaction temperature, and time). The compatibilization was evidenced by "online" monitoring of the melt viscosity during reactive processing of polymer blend and examined by melt volume rate, oscillatory rheology, mechanical testing, and scanning electron microscopy. The effect of selected peroxides on the type of radical reaction was also evidenced for individual thermoplastics. Both L101 and hydrogen peroxide modify the melt viscosity with different effectivity due to different miscibility, decomposition mechanism, and limited reactivity of individual thermoplastics toward primary radicals. Therefore, the efficiency of compatibilization is limited. On the other hand, SEBS‐g‐MAH acts is an "universal" and effective reactive compatibilizer for multicomponent polymeric blend due to combination of covalent and non‐covalent interactions with blended thermoplastics, resulting in the improvement of mechanical properties and morphology of polymer blend. [ABSTRACT FROM AUTHOR]

Plasticised poly(lactic acid) (PLA)-based antimicrobial films were successfully produced via solvent-casting method. For this purpose, PLA copolymer-bearing quaternary ammonium salt in rate of 5 mol% was successfully fabricated through a two-step reaction procedure, i.e. combination of ring-opening copolymerization and copper(I)-catalysed azide–alkyne cycloaddition click reactions. The synthesized polymer was blended at three different amounts (5, 20 and 30% w/w) with commercial PLA which was plasticized with PEG-1000. After the blending process, antimicrobial activity of all the composite films was investigated against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria via contact-active method. It was determined that the films blended with polymer containing quaternary ammonium salt on its backbone had a highly effective antimicrobial activity against both bacteria, even at the lowest blending rate. Besides, the thermo-mechanical behaviours of obtained films were analysed. Thermal property of films was not changed significantly after blending process of antimicrobial polymer. As a result, it can be said that the film which contains antimicrobial polymer at the lowest amount provides the purpose of this work with the highly effective antimicrobial activity and better mechanical properties compared to other films. [ABSTRACT FROM AUTHOR]

Biopolymer-based membranes are eco-friendly alternatives to petroleum-based membranes. However, biopolymers often require harsh membrane fabrication conditions due to their low solubilities, which are incompatible with general non-solvent-induced phase separation (NIPS). Thus, establishing mild blending conditions for NIPS membrane production is needed. This study developed ultrafiltration membranes by blending poly (lactic acid) (PLA) and acetylated cellulose ether (ACE), both of which are derived from renewable resources, using NIPS under mild conditions. We investigated the effects of PLA proportion on the structural, chemical, and thermal properties of the blend membranes and assessed polymer miscibility using theoretical models. Results indicated excellent miscibility with a single glass transition temperature. The 1:1 PL A/ACE membrane demonstrated the lowest water contact angle of 45°, 35 % lower than that of the pure PLA membrane. Additionally, its pure water permeance was 179.4 LMH/bar, significantly higher than 103.4 LMH/bar of the pure PLA membrane. Flux recovery ratio at pH = 4 was 69.5 for the blend membrane as compared to 70.6 for the PLA membrane. At pH = 7, all membranes could be fully recovered via physical washing, even those fouled with bovine serum albumin. This study successfully fabricates PLA/ACE-based membranes with outstanding properties under mild conditions. [Display omitted] • Bio-based poly (lactic acid) (PLA) and acetylated cellulose ether (ACE) were blended. • PLA and ACE had excellent miscibility with a single glass transition temperature. • The PLA/ACE membrane with a 1:1 blend ratio (M 5:5) had the highest hydrophilicity. • The water permeance of M 5:5 was 1.7-fold higher than that of the PLA membrane. [ABSTRACT FROM AUTHOR]

Reactive additives allow to adapt the properties of thermoplastic polymers during processing and for their later use. The chemical modification using multifunctional epoxide styrene-acrylic chain extenders (CE) in reactive processes is by now an established method to prevent degradation and to improve the process ability as well as the final properties of thermoplastics. One of the most common representatives of these CE is better known under its trade name Joncryl®. Since several years ago, Joncryl® ADR owes an ever-growing importance in industry and academia. It can be applied as reactive melt modifier for numerous polymers, mainly polyesters, where it largely affects the rheological properties and the thermal behavior. This review focuses on the reactive behavior of Joncryl® ADR as well as the induced changes in the rheological behavior of the polymers caused by this modification. The Joncryl® ADR incorporation leads to an increased shear viscosity, a higher melt strength and induces strain hardening due to the formation of branched chains and/or even crosslinking. The crystallization is also directly influenced by the changed chain topology. Eventually, this review article extensively addresses the benefits of using Joncryl® for processing such as stabilization, recycling, foaming, and polymer blending. [ABSTRACT FROM AUTHOR]

In this study the as-deposited and heat treated at 423K of conductive blende graphene oxide (GO) / poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) thin films was prepared with different PEDOT:PSS concentration (0, 0.25, 0.5, 0.75 and 1.0)wt% on pre-cleaned glass substrate by spin coating technique. The energy dispersive X-ray Analysis (EDX) show the existence of higher amount of carbon and oxygen related to hydroxyl and carbonyl groups. X)ray diffraction (XRD) analysis of the as-deposited and annealed GO/PEDOT:PSS thin films blend indicated that the film prepared show broad peak around 8.24 corresponding to the (001) level refers to GO, this peak shifted to the lower 2θ with increasing PEDOT:PSS concentration. These results of Fourier transform infrared spectroscopy (FTIR) support the EDX measurement and confirm all the bonds of mixed compounds before and after annealing process. UV-visible spectra of the GO was registered for investigation the peak at ~ 224 nm along with the shoulder at ~ 260 nm. After blending,there are a small shifts in the peaks locations toward the red shift wavelength with increase the concentrations of PEDOT:PSS, while after heat the peaks locations shift toward the blue shift wavelength. [ABSTRACT FROM AUTHOR]

Due to the demand for developing reliable and economical fuel cells, many researchers have focused on durability improvement of hydrocarbon-based proton exchange membranes (PEMs), without compromising performance. Among various techniques, cross-linking and blending show promising potentials by introducing physical and/or chemical bonds between polymer chains and creating a 3D network within their structure. Cross-linking is accomplished through thermal, solvothermal, radiation-assisted, and cross-linker assisted methods, whereas blending is categorized based upon the existing interactions between polymers, namely acid-acid, acid-base, and charge transfer network. This review article discusses the recent achievements of cross-linked and blend hydrocarbon-based PEMs in long-term stability tests and durability studies. Additionally, their salient dimensional, thermo-chemical, and transport properties are highlighted, including the in-situ fuel cell performance and electrochemical diagnostics. Accordingly, cross-linked and blend membranes have shown over 4000 h durability in hydrogen fuel cells and more than 100 times lower methanol cross-over compared to conventional fluorinated membranes, implying significant potential for commercialization. • Durability of cross-linked and blend hydrocarbon-based membranes is reviewed. • Different methods of membrane preparation are comprehensively discussed. • Cross-linking and blending create chemical and physical bonds in polymer structure. • They have shown more than 100 times lower methanol cross-over than PFSA membranes. • Over 4000 h stability obtained in H 2 fuel cell under steady/accelerated condition. [ABSTRACT FROM AUTHOR]

The influence of extensional strain and strain rate on dispersed phase size during blending of a dilute mixture of vinyl polymers, high‐density polyethylene in polystyrene, was examined; the viscosity ratio was substantially larger than four so that shearing was not expected to contribute to drop breakup. Coarse blends were formulated by employing an internal mixer, and these blends were processed through different converging dies attached to the outlet of a capillary viscometer. Variables included the die geometry and the volumetric flow rate. Average dispersed phase sizes were determined by analyzing scanning electron micrographs of sections of strands leaving the viscometer, and it was found that extensional flow was very effective in reducing the dispersed phase size. Coarse blends were also formulated by separately incorporating nanoparticles of hydrophobic fumed silica as well as hydrophilic fumed silica in the blends at a 4 wt% nanofiller level. This resulted in a significant reduction in drop size compared to the previous value; this was likely the result of lowered drop coalescence. These nanoparticle‐containing blends were also subjected to extensional flow, and this resulted in a further reduction in the average dispersed phase size. However, the final result was only slightly better than that obtained previously with the help of extensional flow alone. This suggests the use of nanoparticle incorporation along with employing extensional flow when the presence of nanoparticles provides multifunctionality to the resulting blend. [ABSTRACT FROM AUTHOR]

The effect of an impact polypropylene copolymer (IPC) having excellent stiffness–toughness balance on the microstructure and properties of a blend comprising 80 wt% recycled high density polyethylene (rHDPE) and 20 wt% recycled isotactic polypropylene (rPP) was studied. Morphological observations revealed improved interfacial interactions, a finer dispersion state and a more homogeneous phase morphology upon IPC incorporation into the blend up to 20 wt%. Flexural modulus, flexural strength, tensile strength and tensile ductility were steadily increased with IPC loading, and exhibited 13%, 14%, 35% and 520% improvement at 20 wt% IPC. A monotonic rise in Izod impact energy, accompanied by a transition from semi‐brittle to fully ductile failure mode, was observed with IPC concentration, so that this parameter showed 110% increment at 20 wt% IPC. The change in properties was attributed to the compatibilization, toughening as well as reinforcing effects of the IPC phase in the modified blends. Melting and crystallization of the blends were studied by the DSC technique. Failure mechanisms and micro‐deformations accompanying the impact fracture process of the blends were closely examined, and the role of IPC in improving the toughness and fracture resistance of the modified blends was clarified. The results were interpreted in terms of interfacial strength, efficiency of stress transfer across the phase boundaries, and stability of plastic micro‐deformations during the fracture process. The results clearly demonstrate that simultaneous improvement in stiffness, strength and (impact) toughness of the incompatible rHDPE/rPP blend can be achieved by modification with a properly chosen IPC. The present work addresses some challenges, with respect to stiffness and strength, encountered with the use of conventional elastomeric and/or plastomeric olefin copolymers as common modifiers for polyolefin blends. © 2021 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

Results of our research on crosslinked latexes and polymer nanoparticles will be reported. Goals of this long-term program have been: comparing precoalescence and post-coalescence crosslinking; synthesizing polymer nanoparticle latexes (~ 20 to 25 nm) from a variety of acrylic monomers, including crosslinking and crosslinkable monomers; and blending nanoparticle latexes with compatible conventional (~ 120 to 130 nm) latexes and understanding their effects on film formation and on fundamental and empirical film properties. As we previously reported, blending conventional and nanolatexes in an 85/15 ratio (w/w of polymer solids) effects substantial changes of fundamental film properties. Best results included reducing minimum filming temperatures (MFT) while increasing Young's moduli by factors of two to 17. Substantial improvements in empirical film properties such as gloss (up to 97 at 60°), hardness (increased by 2–5 pencils), block resistance, and adhesion to aluminum were also found. The previous report covered only a single blend ratio. Here we report studies of blends with ratios of conventional to nanoparticle latexes ranging from 92.5/7.5 to 30/70 (w/w). As before, the latexes and nanolatexes are BMA/BA copolymers with 0–4 wt.% of 1,3-butylene glycol dimethacrylate (precoalescence crosslinker) and 0–5 wt.% of diacetone acrylamide (for post-coalescence crosslinking with adipic dihydrazide). Films cast from these blends are subjected to everyday empirical coatings tests and are characterized using instrumental tests including dynamic mechanical analysis (DMA) and modulated differential scanning calorimetry (MDSC). Film formation and film morphology are studied using atomic force microscopy (AFM). The results confirm that blending nanoparticles at ratios up to 50/50 (w/w of polymer solids) can substantially improve certain properties of conventional latex films. For many properties, the optimum ratio is around 85/15 conventional/nano; a 92.5/7.5 ratio also affords substantial improvements. As coatings, the blends have near-zero VOC. [ABSTRACT FROM AUTHOR]

A novel poly(epichlorohydrin- co -ethylene oxide)- g -poly(methyl methacrylate) copolymer (ECO- g -PMMA) was successfully synthesized from a commercially renewable elastomer via the ATRP method. The graft copolymer was investigated as a toughening agent and compatibilizer for polylactide (PLA) and PLA/ECO blends, respectively. Binary blending PLA with the copolymers (5–15 wt%) significantly improved the strain at break of PLA above 200% without a great strength loss. More importantly, the ternary PLA/ECO/ECO- g -PMMA copolymer blends exhibited a remarkably high impact strength of 96.9 kJ/m2 with non-broken behaviors. An interesting phase structure transformation from a typical sea-island structure to a unique quasi-continuous network structure was observed with varying the content of ECO- g -PMMA from 0 to 15 wt% in the ternary blends. The native toughening mechanism analysis indicated the synergistic toughening effect of the good interfacial adhesion and unique quasi-continuous morphology endowed the ternary blends with excellent mechanical performance. [Display omitted] • A novel ECO- g -PMMA copolymer was prepared by a post-polymerization ATRP method. • The graft copolymer is an effective toughening agent and compatibilizer for PLA-based blends. • The graft copolymer offered us supertough sustainable blends with excellent balanced mechanical performances. • A quasi-continuous phase structure in ternary blend offers a greatly high impact toughness with non-broken behaviors. [ABSTRACT FROM AUTHOR]

A high loading rice husk fibre (RHF) incorporated polyolefin blend of recycled polyethylene high-density/poly(ethylene terephthalate) (rPEHD/rPET) biocomposite was produced through extrusion and hot/cold press process. Interfacial modification of biocomposites was conducted through alkalization (sodium hydroxide solution) of fibres, compatibilization (using E-GMA) and/or coupling agent (MA -g -PE) to improve the interaction between components and the homogeneity of materials blending. Alkalization of fibres had improved the impact strength of biocomposites. The compatibilization and coupling effects on immiscible rPEHD/rPET blend and recycled polymer/RH filler, respectively, had led to an enhancement of mechanical performance and morphological stability. Scanning electron microscope micrograph revealed the improved matrix–matrix and filler–matrix interaction through interfacial modification. This investigation had shown that RHF mixed well with rPEHD/rPET/RHF to produce eco-friendly biocomposite products. [ABSTRACT FROM AUTHOR]

Understanding, predicting, and controlling the self‐assembly behavior of stimuli‐responsive block copolymers remains a pertinent challenge. As such, the copolymer blending protocol provides an accessible methodology for obtaining a range of intermediate polymeric nanostructures simply by blending two or more block copolymers in the desired molar ratio to target specific stimuli‐responsiveness. Herein, thermoresponsive diblock copolymers are blended in various combinations to investigate whether the resultant cloud point temperature can be modulated by simple manipulation of the molar ratio. Thermoresponsive amphiphilic diblock copolymers composed of statistical poly(n‐butyl acrylate‐co‐N,N‐dimethylacrylamide) core‐forming blocks and four different thermoresponsive corona‐forming blocks, namely poly(diethylene glycol monomethyl ether methacrylate) (p(DEGMA)), poly(N‐isopropylacrylamide), poly(N,N‐diethylacrylamide), and poly(oligo(ethylene glycol) monomethyl ether methacrylate) (p(OEGMA)) are selected for evaluation. Using variable temperature turbidimetry, the thermoresponsive behavior of blended diblock copolymer self‐assemblies is assessed and compared to the thermoresponsive behavior of the constituent pure diblock copolymer micelles to determine whether comicellization is achieved and more significantly, whether the two blended corona‐forming thermoresponsive blocks exhibit cooperative behavior. Interestingly, blended diblock copolymer micelles composed of p(DEGMA)/p(OEGMA) mixed coronae display cooperative behavior, highlighting the potential of copolymer blending for the preparation of stimuli‐responsive nanomaterials in applications such as oil recovery, drug delivery, biosensing, and catalysis. [ABSTRACT FROM AUTHOR]

Packaging plays a vital role in safeguarding food from environmental factors and contamination. However, the overuse and improper disposal of non-biodegradable plastic packaging materials have led to environmental concerns and health risks. To address these challenges, the development of degradable food packaging films is crucial. Biodegradable polymers, including natural biopolymers like starch (ST) and gelatin (GE), have emerged as promising alternatives to traditional plastics. This review focuses on the utilization of ST-GE blends as key components in composite films for food packaging applications. We discuss the limitations of pure ST-GE films and explore methods to enhance their properties through the addition of plasticizers, cross-linkers, and nanoparticles. The blending of ST-GE, facilitated by their good miscibility and cross-linking potential, is highlighted as a means to improve film performance. The review also examines the impact of various additives on the properties of ST-GE blend films and summarizes their application in food preservation. By providing a comprehensive overview of ST-GE hybrid systems, this study aims to contribute to the advancement of sustainable and effective food packaging solutions. [Display omitted] [ABSTRACT FROM AUTHOR]

Polymer films composed of polypropylene (PP) and poly(vinylidene fluoride) (PVDF) have been fabricated by extrusion with filming system. Owing to the low content of crystallites and the lubricant of carbon black, the commercial product PVDF 370 can be compatible with PP by simply blending at the molten state and the obtained film has improved dielectric constant (ɛ′ = 4.5) and reduced dielectric loss (tan δ = 0.5%) at 1000 Hz. The modified dielectric properties result from the high dielectric constant of PVDF and low dielectric loss of PP. In addition, by introducing the third polymer, low-density polyethylene (LDPE), the dielectric constant of the ternary blends (PP/PVDF 370/LDPE) can further be increased.

Destruction resistance such as start-up wear resistance characteristics of vitamin E (dl-α-tocopherol) blended ultra-high molecular weight polyethylene (UHMWPE) were evaluated using the destruction energy index (DEI). The DEI is used to evaluate wear-like destruction, by minimising the effects of viscosity at the sliding interface, and is estimated using newly designed friction testers. In this experiment, silicone oils of different viscosities were used to determine micro displacement up to a start-up point, and the DEI of the UHMWPE was changed from 17.48 to 1.84 μJ by adding vitamin E. The results suggest that the blending with vitamin E reduces destruction of UHMWPE at start-up friction in silicone oils.

Abstract Aqueous binders have recently received great attention for lithium ion batteries due to its good stability and safety. Herein, poly (acrylic acid)/poly (vinyl alcohol) (PAA/PVA) blends have been used as a binder for lithium iron phosphate (LiFePO 4 /C) cathodes. This blending system not only can form a stable network by hydrogen-bonding interactions leading to an increase in the amount of binder covering the surface of active materials, but also can significantly enhance the adhesion strength of electrodes. Additionally, The conductive agent and active materials are uniformly distributed due to the interaction between PAA/PVA blending binder and electrode materials, which it is beneficial to Li+ conduction in the electrode. These unique properties result in lower polarization and interfacial resistance of the electrode, thus considerably overcoming the limitation of LiFePO 4 /C electrodes for electrochemical performance. It is believed that this blending binder has a great potential to be used for commercial lithium ion batteries. Highlights • PAA/PVA blends have been successfully used as a binder for LiFePO 4 /C cathodes. • A stable network by hydrogen-bonding interactions was formed in this blending system. • An increase in the amount of binder covering the active materials was obtained. • An improvement adhesion strength of electrodes was obtained. • Superior electrochemical properties of the electrodes with this binder were obtained. [ABSTRACT FROM AUTHOR]

Abstract A series of copolymers FD10 , FD21 , FD11 , FD12 and FD01 have been designed and synthesized via copolymerization of 3,3′-difluoro-2,2′-bithiophene (FTT) and two electron-deficient units, fluorinated benzothiadiazole (FBT) and diketopyrrolopyrrole (DPP), respectively. These terpolymers exhibit broad absorption ranging from 400 nm to 900 nm. The polymer solar cells (PSC) were prepared from these terpolymers as donor and [6,6]-phenyl-C 71 -butyric acid methyl ester (PC 71 BM) as acceptor. A power conversion efficiency (PCE) value of 6.41% for terpolymer FD21 with a high short-circuit current density (J sc) of 12.52 mA cm−2 is achieved via tuning the composition of FBT and DPP unit (FBT:DPP = 2:1). The binary polymer FD10 shows the highest open-circuit voltage (V oc) of 0.86 V. In order to further improve the photovoltaic performance of the terpolymer, the blends of FD10 and FD21 with different weight ratio were prepared and applied as donor materials for PSC. The highest PCE of 7.04% with a J sc of 13.79 mA cm−2 and a V oc of 0.77 V for blend FD10 : FD21:PC 71 BM (0.5:0.5:1.5) was attained due to more balanced mobility (μ h /μ e = 1.02) and an appropriate microphase separation. This work provides an effective strategy to improve photovoltaic performance of terpolymers via synergetic effects of copolymerization and blending. Graphical abstract Image 1 Highlights • A series of D-A1-D-A2 terpolymers have been designed and synthesized via copolymerization. • These terpolymers exhibit broad absorption and high charge mobility. • A moderate PCE of 7.04% for blend FD10:FD21:PC 71 BM (0.5:0.5:1.5) was obtained. [ABSTRACT FROM AUTHOR]

Abstract A significant problem associated with the use of polyhydroxybutyrate and its copolymers in food packaging is their high initial crystallinity coupled with an ability to undergo secondary crystallisation over time which results in progressive embrittlement. This paper details work undertaken to hinder the secondary crystallisation process through the blending of poly(hydroxybutyrate- co -hydroxyvalerate) (PHB- co -HV) with mono-, di- and tri-saccharides. Following blending, the melt viscosity and melting point were observed to decrease with increasing saccharide concentration. The incorporation of saccharides into PHB- co -HV did not completely prevent the secondary crystallisation process, however, the rate of change in the Young's modulus and ultimate tensile stress were significantly reduced. The percentage change in the mechanical properties of these blends was found to be directly related to the size of the saccharide which was deemed to be as a result of greater steric hindrance and an increasing number of hydroxyl groups available for interaction with PHB- co -HV. This, along with the reduction in melt viscosity and melting point, makes the addition of mono, di and tri saccharides worthwhile for improving the processability and prolonging the effective life time of products made from PHB- co -HV. Highlights • Saccharides can reduce secondary crystallisation and embrittlement of PHB- co -HV. • The larger the saccharide the slower the rate of secondary crystallisation. • Reduction caused by greater steric hindrance and more interacting groups present. • Saccharides can also reduce the melting and therefore processing temperature. • The effective stability of PHB- co -HV products are increased. [ABSTRACT FROM AUTHOR]

In the last few years, efforts to broaden PILs properties, structures, functionalities, and applications have grown rapidly. One of their interesting potential uses is as antimicrobial systems, due to their versatility and capacity to be adjusted in different morphologies, sizes, and surface charges. This review gathers the recent advances in antimicrobial materials based on PILs. Initially, the synthesis of PILs with antimicrobial activity, showing the influence of the chemical structure, whether is cationic or anionic and their corresponding counter-ions, is pointed out. Equally, most of these PILs present modest mechanical performance that turn researchers to overcome it by grafting them to different surfaces, crosslinked with other monomers or by simple blending with polymers. Moreover, the nature of PILs makes them regulators of size and shape of inorganic antimicrobial particles, enhancing their effectivity. [ABSTRACT FROM AUTHOR]

The main goal of this study was to synthesise and characterise different formulations based on alginate and alginate/chitosan microspheres containing nanoselenium (nano‐Se) for controlled delivery applications. Nanosize elemental selenium was produced by using probiotic yogurt bacteria (Lactobacillus casei) in a fermentation procedure. The structural and morphological characterisation of the microspheres was performed by Fourier transform infrared (FTIR), X‐ray diffraction (XRD) and scanning electron microscopy (SEM) analysis. FTIR and XRD pattern indicated that was an effective cross‐linking of selenium nanoparticles within the polymeric matrix in both cases. The SEM images reveal that selenium nanoparticles are mainly exposed on the surface of alginate, in contrast to porous structure of alginate/chitosan/nano‐Se, interconnected in a regular network. This architecture type has a considerable importance in the delivery process, as demonstrated by differential pulse voltammetry. Selenium release from both matrices is pH sensitive. Moreover, chitosan blended with alginate minimise the release of encapsulated selenium, in simulated gastric fluid, and prolong the duration of release in intestinal fluid. The overall effect is the enhancement of total percentage release concomitant with the longer duration of action. The authors' formulation based on alginate/chitosan is a convenient matrix to be used for selenium delivery in duodenum, caecum and colon. [ABSTRACT FROM AUTHOR]

To overcome the limitations of polylactic acid, alterations are needed to enhance its toughness, to improve handling and for various applications. Extensive studies were reported, mainly in the area of blends with renewable resource polymer blends. Better phase dispersion between the blend materials is achieved either by reactive mixing of the two components or by incorporation of a block copolymer compatibilizer, finally showing highly enhanced property. In this article, the recent research progress of different toughening processes of PLA via blending is reviewed and a detailed understanding about toughening of PLA using biodegradable or renewable polymers has been established. [ABSTRACT FROM AUTHOR]

This study was conducted to synthesize poly(L-lactide)–poly(ethylene glycol)–poly(L-lactide) triblock copolymer (PEGLA) with different poly(L-lactide) block length, and explore its applicability in a blend with linear poly(L-lactide) (3051D NatureWorks) with the intention of improving heat seal and adhesion properties at extrusion coating on paperboard. Poly(L-lactide)–poly(ethylene glycol)–poly(L-lactide) was obtained by ring opening polymerization ofL-lactide using poly(ethylene glycol) (molecular weight 6000 g mol−1) as an initiator and stannous octoate as catalyst. The structures of the PEGLAs were characterized by proton nuclear magnetic resonance spectroscopy. The melt flow and thermal properties of all PEGLAs and their blends were evaluated using dynamic rheology and differential scanning calorimeter. All blends containing 10 wt% of PEGLAs displayed similar zero shear viscosities to neat poly(L-lactide), while blends containing 30 wt% of PEGLAs showed slightly higher zero shear viscosity. However, all blends displayed higher shear thinning and increased melt elasticity (based on tan δ). No major changes in thermal properties were distinguished from differential scanning calorimetric studies. High molecular weight PEGLAs could be used in extrusion coating with 3051D without problems. [ABSTRACT FROM PUBLISHER]

Due to its low density and poor flowability, raw biomass may not be an economically viable feedstock for the production of biofuels. However, mechanical densification can be employed to improve its viability. In this study, the flow properties (compressibility, shear, and wall friction) of “pure” feedstocks (corn stover, hybrid poplar, switchgrass and Miscanthus ), and feedstock blends, are investigated and compared to measured pelleting energy consumption values. As anticipated, the more compressible materials required lower pelletization energies. Conversely, the less flowable feedstocks (i.e., the materials with higher cohesion and yield strength) were less energy intensive to pellet. In addition, the flowability parameters of the blended materials could be predicted by averaging the measured flow parameters of their pure feedstock constituents. Therefore, only the flow characteristics of the pure feedstocks need to be directly measured, while the flowability of a blended feedstock with a known blend ratio can be accurately inferred. A model was also developed to calculate the required pressure to pellet a particular feedstock, pure or blended, based on its flowability parameters (namely compressibility and wall friction). Strong correlation was observed between the measured pelleting energy consumption and the predicted pelleting pressure values. This newly developed model allows for a material's pelleting feasibility to be assessed without having to physically pelletize the material. [ABSTRACT FROM AUTHOR]

• CAB/CA blends cannot be characterized as miscible/immiscible. • CAB/CA blends and respective copolymers exhibit two thermal transitions. • New interpretations for the existence of two transitions in polymer blends. • The new term "heterogeneous mixtures of compatible polymers" is introduced. Differential Scanning Calorimetry (DSC) and micro-Raman Spectroscopy were used to study blends of cellulose acetate (CA) with cellulose acetate butyrate (CAB) prepared by solution blending. It is shown that these blends combine two characteristics: (a) values of enthalpy of mixing (ΔH mix) and Gibbs free energy of mixing (ΔG mix) close to zero, due to similar molecular interactions and (b) multiple, more or less equivalent, minimum values of ΔG mix leading to non-equilibrium structures, mainly due to the inherent microheterogeneity of pure polymers. New interpretations are provided for the observed thermal behavior (e.g. existence of multiple thermal transitions) of the blends. None of the terms miscible, partially miscible or immiscible is truly appropriate to characterize these blends. The thermal behavior of pure polymers, blends and chemically synthesized copolymers of similar degree of substitution is pretty much alike, thus, development of copolymers by physical blending of cellulose esters seems to be feasible. [ABSTRACT FROM AUTHOR]

In this work, the crystalline morphologies and mechanical properties of olefin multiblock copolymer (OBC) were regulated by blending with polymers possessing architecture similar to the constituent blocks. In order to understand the influence of multiblock architecture on the interaction between OBC and blended substances, ethylene-octene random copolymer (ORC) with similar crystallinity was blended with corresponding substances for comparison. We found that polyethylene (PE) chains, which possessed architecture resembling hard blocks, were inclined to cocrystallize with OBC and form remarkable lamellar structure in their blends. On the contrary, they aggregated together in ORC matrix and developed crystals similar to pure PE. The distinct crystalline properties were closely correlated to their state in the melt as revealed by Time–Temperature superposition examinations. The results of tensile tests exhibited that the strength of OBC samples could be improved without great depression of tenacity when appropriate amount of PE was blended. This might be ascribed to the good compatibility between added PE and OBC hard blocks considering their similar chain architecture. The findings contribute to understanding the relationship between morphologies and apparent properties of multi-block copolymer-based blends, which can be significant to achieve target mechanical properties for multiblock copolymers by a simply blending approach. [ABSTRACT FROM AUTHOR]

Liquid crystal is a material which is between solid and liquid phase and commonly called mesophase . Blends of liquid crystal are of great interest because of their unique optical properties. Blending in this study using two monomers of liquid crystal were cholesteryl acrylate and methyl phenyl benzoyl acrylate. The polymerization process using uv curing techniques by irradiation UV ray and without irradiation UV ray. Polymerization of blending liquid crystal acrylate using initiator 2-hydroxy-2-methyl-1-phenylpropane. Based on peak at GPC curve of polymerization by irradiation UV ray, type of that polymer is copolymer. Therefore the polymerization without UV ray, type of that polymer is homopolymer. SEM images of liquid crystal acrylate polymer showed lamella chain models that are characteristic of a polymer chains. Type of polymer liquid crystal acrylate was the type of Side Chain Liquid Crystalline Polymers (SCLCPs). Therefore acrylate polymer liquid crystal in this research has semi-crystalline phase, which contained crystalline phase and amorphous phase on the XRD pattern. The results of FT-IR spectroscopic characterization of the two monomers showed a peak at the wave number of 1600.43 cm -1 and 1622.86 cm -1 which indicates a double bond (C=C) were obtained from acrylation. While the spectroscopy on the product blending the wave number of the peak regions is reduced that shows that carbon double bonds (C=C) in the acrylate group has polymerized. It also strengthened with a very sharp peak for CC functional groups on the wave number of 2855.15 cm -1 . The results of this study indicate that the liquid crystal polymer acrylic polymerization results with radiation UV ray and without UV ray, respectively absorb light in the UV wavelength region 363 nm and 351 nm. [ABSTRACT FROM AUTHOR]

In the present research, blending of polymers used in electrical and electronic equipment, i.e. acrylonitrile–butadiene–styrene terpolymer, polycarbonate and polypropylene, was performed in a twin-screw extruder, in order to explore the effect process parameters on the mixture properties, in an attempt to determine some characteristics of a fast and economical procedure for waste management. The addition of polycarbonate in acrylonitrile–butadiene–styrene terpolymer seemed to increase its thermal stability. Also, the addition of polypropylene in acrylonitrile–butadiene–styrene terpolymer facilitates its melt processing, whereas the addition of acrylonitrile–butadiene–styrene terpolymer in polypropylene improves its mechanical performance. Moreover, the upgrading of the above blends by incorporating 2 phr organically modified montmorillonite was investigated. The prepared nanocomposites exhibit greater tensile strength, elastic modulus and storage modulus, as well as higher melt viscosity, compared with the unreinforced blends. The incorporation of montmorillonite nanoplatelets in polycarbonate-rich acrylonitrile–butadiene–styrene terpolymer/polycarbonate blends turns the thermal degradation mechanism into a two-stage process. Alternatively to mechanical recycling, the energy recovery from the combustion of acrylonitrile–butadiene–styrene terpolymer/polycarbonate and acrylonitrile–butadiene–styrene terpolymer/polypropylene blends was recorded by measuring the gross calorific value. Comparing the investigated polymers, polypropylene presents the higher gross calorific value, followed by acrylonitrile–butadiene–styrene terpolymer and then polycarbonate. The above study allows a rough comparative evaluation of various methodologies for treating plastics from waste from electrical and electronic equipment. [ABSTRACT FROM AUTHOR]

The phenol-containing carboxyl-functionalized multi-walled carbon nanotubes/poly(amide-imide) (f-MWCNTs/PAI) composite films were prepared by a simple sonically assisted solution casting technique. The f-MWCNTs are dispersed homogeneously in the PAI matrix while the structures of the PAI and MWCNTs are stable in the preparation process. With the incorporation of f-MWCNTs, the mechanical properties of the resultant nanocomposite films were greatly improved due to the strong interfacial interaction between the f-MWCNTs and the PAI matrix. The dispersion of f-MWCNTs and interfacial interaction were investigated through field emission scanning and transmission electron microscopy. The unique character of CNT dispersed in the PAI matrix resulted in the physical barrier effect against the thermal decomposition, leading to the improvement in the thermal stability of the MWCNT/PAI composites. [ABSTRACT FROM AUTHOR]

Polysulfone is one of the most common used polymers for preparation of nanofiltration membranes. These membranes are highly susceptible to fouling problems because of their surface hydrophobic nature. In this paper a new approach for modification of polysulfone to overcome the fouling problems was introduced. The modification was carried out via blending of polysulfone with a modified grafted polysulfone using atom transfer radical polymerization (ATRP) method. The modified grafted polysulfone was synthesized via ATRP grafting of n-butylacrylate from chloromethylated polysulfone. The graft copolymers were characterized by FT-IR, NMR, DSG and TGA techniques. Furthermore, surface morphology and performance of the corresponding membrane were studied in detail using SEM and pure water flux and salt rejection experiments, respectively. The results indicated that the prepared modified polysulfone membranes have high surface hydrophilicity and therefore better fouling resistance and very good water permeability. [ABSTRACT FROM AUTHOR]

Highlights: [•] Sulphonated hydrocarbon proton exchange membranes were synthesized and characterized. [•] These were based on sulphanilic acid tethered poly(methyl vinyl ether-alt-maleic anhydride). [•] The presence of nanopores in membrane was confirmed by SEM and AFM analyses. [•] The values of conductivity and proton diffusivity of the membrane was 0.0045S/cm and 10−10 m2/s. [•] Statistical analyses provide the understanding of the obtained electro-chemical properties. [Copyright &y& Elsevier]

Polymer blends have been considered a promising strategy to tailor drug release. In order to achieve gastroresistance and controlled release, Pullulan, a polysaccharide, and Eudragit® S100, an enteric polymer were selected to prepare microparticles for oral delivery of risedronate, an antiresorptive drug associated with GI tract injuries. Blend microparticles were prepared by spray-drying technique at 3 Pullulan and Eudragit® S100 ratios (MP2:1, MP1:1 and MP1:2) and were characterized in terms of yield, particle size, encapsulation efficiency, morphology, moisture content, flowability and in vitro drug release profiles. Microparticles presented yields between 31 and 42%, encapsulation efficiencies close to 100%, moisture contents lower than 11%, particle size ranging from 2.9 to 4.8μm and narrow distribution. In the gastric medium, MP1:2 showed the best gastroresistance profile. In the intestinal fluid, all samples were able to prolong drug release. MP1:2 was compressed into tablets with or without polyvinylpyrrolidone. Both tableted microparticles could be obtained with acceptable average weights, drug content close to 100%, sufficient hardness and low friability. In vitro studies showed that tablets maintained the gastroresistance observed for microparticles and were also able to prolong risedronate release. In conclusion, Pullulan/Eudragit® S100 microparticles are promising alternatives for the oral delivery of risedronate in the future. [ABSTRACT FROM AUTHOR]

Highlights: [•] Carboxymethyl konjac glucomannan (CMKGM) and soy protein isolate (SPI) were used. [•] Blended films of CMKGM and SPI were prepared. [•] Hydrogen bonding and Maillard reactions explain CMKGM and SPI interations. [•] Biopolymer interactions led to improved properties of the blended films. [•] Tensile strength and elongation at break were greater in the blended films. [ABSTRACT FROM AUTHOR]

Research interest is growing in the potential to strategically mix selected polymers to modify properties and reduce the cost of resultant blends. Renewable resource-derived spinifex resin-based polyurethane (RPU) can be considered a potential bio-alternative to conventional petroleum-based polymers. However, its inherent weak mechanical properties severely limit its range of applications. This study aimed to prepare a useful novel polymer by solution blending of polyurethane prepared from spinifex resin (endemic to Australia) and commercially available thermoplastic polyurethane (TPU). Properties of the prepared polymer blends were characterized using various techniques. [ABSTRACT FROM PUBLISHER]

The lubrication behavior of two series of binary blends containing S-4: PAO-100 or S-4: PIB have been followed. Each series contains 5%, 10%, 15%, 20%, and 25% of PAO-100 or PIB. The results indicate that upon addition of PAO-100, viscosities, viscosity index, and flash point increase in a linear fashion. Meanwhile, pour point, TAN, and specific gravity remain constant. In the case of PIB, viscosities increase in an exponential manner, viscosity index increases then remains constant, flash point drops, and then leftovers remain constant. Other properties do not change considerably. The rheological properties of 15% and 25% blends of S-4: PAO-100 blends are similar to S-6 and S-8, respectively. Similar conditions exist for 5% and 10% of S-4: PIB blends. A motor oil which has been formulated by 15% S-4: PAO blend and a hydraulic oil which has been formulated by 5% S-4: PIB blend have shown good performance characteristics. [ABSTRACT FROM PUBLISHER]

Several mixtures of SN 500 and polyisobutene in which the weight percentages of polyisobutene varied from 0 to 20 were made. The important lubrication properties of the recent blends were then followed by standard methods. The results indicate systematic increase in viscosities at 40 and 100°C, as well as viscosity index, flash point, and specific gravity. In the case of pour point, sulfur content, color, and total acid number the reverse trend was observed. The lubrication properties of 83:17 showed good accordance with corresponding properties due to Bright stock 150. In addition the mixture showed the advantages of lower sulfur content as well as higher viscosity index and aniline point. Equalization of gear oil Esso GX from Esso Company and hydraulic oil Shell Tellus T32 from Shell Company by 83:17 mixture was successful. [ABSTRACT FROM PUBLISHER]

ABSTRACT Nanostructured amorphous bulk polymer samples were produced by processing them with small molecule hosts. Urea (U) and gamma-cyclodextrin (γ-CD) were utilized to form crystalline inclusion compounds (ICs) with low and high molecular weight as-received (asr-) poly(vinyl acetate) (PVAc), poly(methyl methacrylate) (PMMA), and their blends as included guests. Upon careful removal of the host crystalline U and γ-CD lattices, nanostructured coalesced (c-) bulk PVAc, PMMA, and PVAc/PMMA blend samples were obtained, and their glass-transition temperatures, Tgs, measured. In addition, non-stoichiometric (n-s)-IC samples of each were formed with γ-CD as the host. The Tgs of the un-threaded, un-included portions of their chains were observed as a function of their degree of inclusion. In all the cases, these nanostructured PVAc and PMMA samples exhibited Tgs elevated above those of their as-received and solution-cast samples. Based on their comparison, several conclusions were reached concerning how their molecular weights, the organization of chains in their coalesced samples, and the degree of constraint experienced by un-included portions of their chains in (n-s)-γ-CD-IC samples with different stoichiometries affect their chain mobilities and resultant Tgs. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013, 51, 1041-1050 [ABSTRACT FROM AUTHOR]

A series of grafted ethylene-octene copolymers using itaconic acid (ITA) and styrene (St) as grafted monomers (POE-g-ITA, POE-g-(ITA-St)) were preparedviamelt grafting technique by twin screw extrusion. The structure of grafted copolymer was characterized by FT-IR. The monomer and initiator concentration and the percent content of St in grafted monomers were also explored in the effect on the graft ratio (GR) and melt flow rate (MFR) of POE-g-ITA. TheGRof POE-g-ITA reached 1.36% when when the ratio of POE:ITA:DCP is 94:6:0.36, and theGRof POE-g-(ITA-St) reached 1.44% when the ratio of POE:ITA:St:DCP = 94:3:3:0.18. The compatibilizer POE-g-ITA was introduced into PA6/POE blend by twin screw extrusion. The mechanical properties and morphological structure were investigated. The results revealed that the impact strength of the PA6/POE blend containing 5 phr of POE-g-ITA was enhanced 12.78 times compared with pure PA6. The crystallinity (Xc) of PA6 phase increased gradually when the compatibilizer POE-g-ITA was introduced into PA6/POE blends, although the melting point (Tm) of PA6 phase had no obvious change. The interface between PA6 and POE phase became indistinct and the compatibility was significantly increased. [ABSTRACT FROM AUTHOR]

In this study, the melt-spinning and stretching processes were used to prepare polyvinylidene fluoride (PVDF)/polyacrylonitrile (PAN) blend hollow-fiber membranes. These blend membranes have a higher tensile strength than those prepared via the wet phase inversion method. The influence of stretching temperature and draw ratios on the membrane microstructure, pure water flux, and porosity of the membranes was studied. The draw ratio and the stretching temperature can greatly affect the morphology and the permeation performance of the membranes. The Fourier transform infrared spectra demonstrate the differences in the PVDF/PAN blend membranes before and after hydrolysis. The water flux of the hydrolyzed PVDF/PAN blend membranes is sensitive to pH value and salt ionic strength. The effects of different salt ions on the permeability of the hydrolyzed membranes were also investigated. [ABSTRACT FROM PUBLISHER]

Simulations based on molecular dynamics and mesodyn theories were used to investigate the compatibility, morphology evolution of polypropylene/polycarbonate (PP/PC) blends, and the relationship between the composition and microstructure. Results of Flory-Huggins interaction parameters, integral structure factor, X-ray intensity, free-energy density, and order parameters all indicated that phase separations occurred in all PP/PC blend systems, and poor compatibility was exhibited for this polymer pair. The systems of PP/PC = 54/46, PP/PC = 31/69, and PP/PC = 18/82 showed stronger immiscibility and the faster separation process, while the systems of PP/PC = 82/18 and PP/PC = 5/95 showed less immiscibility and a slower separation process. Compared with the results of mechanical properties tests, the appearance of a cocontinuous structure obtained from simulation corresponds to the transition point of impact strength and tensile strength. After transition, the mechanical properties of the blends depended on the properties of the PC matrix, and the impact strength and tensile strength were both clearly enhanced. As the simulation steps increased, the morphology of PP/PC = 54/46 blend developed into a double-lamellar structure by coarsening of PC phase from initial homogeneous configuration. In addition, the compatibilizing effect of SEBS was also investigated at the microscale, and varying the content of PS block in SEBS has little effect on the morphology of blend. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]