Compatibility Of Blends Research Articles

Integrated Approach for Enhancement of Vapor Compression Refrigeration Systems with Spiral Condenser Retrofitting and Refrigerant Blend Compatibility

An integrated approach for enhancing Vapor Compression Refrigeration Systems (VCRS) through Spiral Condenser retrofitting and compatibility with refrigerant blends is proposed in this paper. The objectives include the design and development of an experimental setup compatible with refrigerant blends, experimentation and analysis of results for retrofitting the setup with a Spiral Condenser, validation of experimental results, and determination of system energy effectiveness and payback period. The methodology involves systematic design, experimentation, validation, and analysis, culminating in insights into VCRS enhancement strategies. The findings contribute to advancing VCRS technology, optimizing performance, and promoting sustainability in refrigeration systems.

Biopolymeric Blends of Thermoplastic Starch and Polylactide as Sustainable Packaging Materials.

The improper disposal of plastics is a growing concern due to increasing global environmental problems such as the rise of CO2 emissions, diminishing petroleum sources, and pollution, which necessitates the research and development of biodegradable materials as an alternative to conventional packaging materials. The purpose of this research was to analyse the properties of biodegradable polymer blends of thermoplastic potato starch (TPS) and polylactide, (PLA) without and with the addition of citric acid (CA) as a potential compatibilizer and plasticizer. The prepared blends were subjected to a comprehensive physicochemical characterization, which included: FTIR-ATR spectroscopy, morphological analysis by scanning electron microscopy (SEM), determination of thermal and mechanical properties by differential scanning calorimetry (DSC), water vapour permeability (WVP), as well as biodegradation testing in soil. The obtained results indicate an improvement in adhesion between the TPS and PLA phases due to the addition of citric acid, better homogeneity of the structure, and greater compatibility of the polymer blends, leading to better thermal, mechanical and barrier properties of the studied biodegradable TPS/PLA polymer blends. After conducting the comprehensive research outlined in this paper, it has been determined that the addition of 5 wt.% of citric acid serves as an effective compatibilizer and plasticizer. This supplementation achieves an optimal equilibrium across thermal, mechanical, morphological, and barrier properties, while also promoting material sustainability through biodegradation. In conclusion, it can be stated that the use of thermoplastic starch in TPS/PLA blends accelerates the biodegradation of PLA as a slowly biodegradable polymer. While the addition of citric acid offers significant advantages for TPS/PLA blends, further research is needed to optimize the formulation and processing parameters to achieve the desired balance between mechanical strength, thermal and barrier properties and biodegradability.

Crystallization behavior and compatibility analysis of palm kernel stearin/anhydrous milk fat blends and application.

In this paper, the compatibility, phase behavior, and crystallization properties of the binary blends of palm kernel stearin (PKS) and anhydrous milk fat (AMF) were investigated by analyzing the solid fat content (SFC), thermal properties, polymorphism, and microstructure, with the aim of providing theoretical guidance for the blending of oils. The results showed that the PKS content primarily determined the SFC trend of the binary blends. However, the binary blends demonstrated poor miscibility and eutectic behavior was predominantly observed in the system, particularly at higher temperatures. Only α and β' forms appeared in this blended system. Simultaneously, the addition of PKS elevated the liquid phase transition temperature of the binary blends, considerably significantly increased their crystallization rate when the addition of PKS was more than 20% and increased the density and size of the fat crystals. Finally, the mixing design optimization method was used to get the most suitable ratio of the binary blends in the refrigerated cream system with PKS:AMF to be 0.914:0.086. The cream prepared with the above binary blends was indeed superior in overrun and firmness and had high stability. PRACTICAL APPLICATION: Some fats with special advantages are often limited in their wide application because of their poor crystallization ability. In this paper, the crystallization ability of fats is improved, and their application scenarios are increased through the combination of fats, so as to provide reference for the production of special fats for food.

Bactericidal Chitosan Derivatives and Their Superabsorbent Blends with ĸ-Carrageenan.

The aim of this work is research dedicated to the search for new bactericidal systems for use in cosmetic formulations, dermocosmetics, or the production of wound dressings. Over the last two decades, chitosan, due to its special biological activity, has become a highly indispensable biopolymer with very wide application possibilities. Reports in the literature on the antibacterial effects of chitosan are very diverse, but our research has shown that they can be successfully improved through chemical modification. Therefore, in this study, results on the synthesis of new chitosan-based Schiff bases, dCsSB-SFD and dCsSB-PCA, are obtained using two aldehydes: sodium 4-formylbenzene-1,3-disulfonate (SFD) and 2-pyridine carboxaldehyde (PCA), respectively. Chitosan derivatives synthesized in this way demonstrate stronger antimicrobial activity. Carrying out the procedure of grafting chitosan with a caproyl chain allowed obtaining compatible blends of chitosan derivatives with κ-carrageenan, which are stable hydrogels with a high swelling coefficient. Furthermore, the covalently bounded poly(ε-caprolactone) (PCL) chain improved the solubility of obtained polymers in organic solvents. In this respect, the Schiff base-containing polymers obtained in this study, with special hydrogel and antimicrobial properties, are very promising materials for potential use as a controlled-release formulation of both hydrophilic and hydrophobic drugs in cosmetic products for skin health.

A Vitrimer Acts as a Compatibilizer for Polyethylene and Polypropylene Blends.

Polymer compatibilization plays a critical role in achieving polymer blends with favorable mechanical properties and enabling efficient recycling of mixed plastic wastes. Nonetheless, traditional compatibilization methods often require tailored designs based on the specific chemical compositions of the blends. In this study, we propose a new approach for compatibilizing polymer blends using a dynamically crosslinked polymer network, known as vitrimers. By adding a relatively small amount (1-5 w/w%) of a vitrimer made of siloxane-crosslinked high-density polyethylene (HDPE), we successfully compatibilized unmodified HDPE and isotactic polypropylene (iPP). The vitrimer-compatibilized blend exhibited enhanced elongation at break (120 %) and smaller iPP domain sizes (0.4 μm) compared to the control blend (22 % elongation at break, 0.9 μm iPP droplet size). Moreover, the vitrimer-compatibilized blend showed significantly improved microphase stability during annealing at 180 °C. This straightforward method shows promise for applications across various polymer blend systems.

A Vitrimer Acts as a Compatibilizer for Polyethylene and Polypropylene Blends

AbstractPolymer compatibilization plays a critical role in achieving polymer blends with favorable mechanical properties and enabling efficient recycling of mixed plastic wastes. Nonetheless, traditional compatibilization methods often require tailored designs based on the specific chemical compositions of the blends. In this study, we propose a new approach for compatibilizing polymer blends using a dynamically crosslinked polymer network, known as vitrimers. By adding a relatively small amount (1–5 w/w%) of a vitrimer made of siloxane‐crosslinked high‐density polyethylene (HDPE), we successfully compatibilized unmodified HDPE and isotactic polypropylene (iPP). The vitrimer‐compatibilized blend exhibited enhanced elongation at break (120 %) and smaller iPP domain sizes (0.4 μm) compared to the control blend (22 % elongation at break, 0.9 μm iPP droplet size). Moreover, the vitrimer‐compatibilized blend showed significantly improved microphase stability during annealing at 180 °C. This straightforward method shows promise for applications across various polymer blend systems.

Biodegradable composites made from maize flour filled with olive husk fibers

The development of biomaterials based on maize flour reinforced with natural fiber was studied with the aim of replacing conventional polymers of petrochemical origin and to simplify assimilated rubbish managing strategies, which reduces the pollution of the environment. In this study, several composites based on plasticized maize flour (PMF) reinforced by the olive husk flour (OHF) in a range from 10% to 40% (wt.%) have been produced with double screw extruder. 15% (wt.%) of low-density polyethylene (LDPE) and graft polyethylene combined with maleic anhydride (PE-g-MA) bonding substance at 5 (wt.%) were added to obtain high mechanical characteristics and improve blend compatibility. Scanning electron microscope (SEM) analysis showed that the fibers were well dispersed in matrix. The Fourier-transform infrared (FTIR) spectroscopy analysis revealed an increase in the absorption bands characteristic of hydroxyl groups and the anhydroglucose ring O-C stretch by raising OHF amount in composites. Thermal stabilization and density of composites increase with the percentage of fiber. For fiber weights of 10 and 40 (wt.%), the tensile strength increased as of 8.4 to 16.4 MPa and the Young modulus as of 70 to 245%, respectively. The biodegradability of samples was tested by burying them in the soil for 90 days. The weight loss test showed that the biodegradability accelerated with the increase in OHF quantity in the PMF. The latter finding was confirmed by FTIR analysis and deteriorated surface of samples examined by SEM analysis.

The Influence of Nano Bentonite Filler Material and Cyclic Natural Rubber Grafted Oleic Acid as a Compatibilizer on the Blend of Cyclic Natural Rubber/Polyamide

Cyclic natural rubber (CNR) and polyamide (PA) cannot blend homogeneously due to their differing polarities. CNR is nonpolar with low surface tension, while PA is polar with high surface tension. To achieve a homogeneous and compatible CNR/PA blend, a CNR-g-OA compatibilizer is required. This study aims to investigate the influence of CNR-g-OA and nano bentonite on the physical and chemical properties of the PA/CNR mixture. The research findings indicate successful grafting of OA onto CNR, resulting in CNR-g-OA formation. Based on electron microscope structural analysis, the CNR/PA mixture yields a homogeneous and compatible blend. In conclusion, CNR-g-OA and nano bentonite can enhance the quality of the PA/CNR blend by producing a homogeneous and compatible mixture

A new approach for grafting plasticized cellulose acetate biodegradable plastic with maleic anhydride: Processing and characterization

AbstractGrafting polymers with reactive maleic anhydride is a common approach for the synthesis of new material with the capability of acting as a compatibilizer in polymer blends. Accordingly, this research showed a new approach for grafting maleic anhydride onto renewable cellulose acetate using an initiator. The grafting process through extrusion showed good stability with continuous production of all grafted samples. Moreover, two different grafting processes, namely one‐step and two‐step processes, were shown to produce materials with very similar characteristics. Grafting of maleic anhydride onto cellulose acetate by reacting with its hydroxyl groups was confirmed by both Fourier transform infrared spectroscopy and nuclear magnetic resonance analysis. Rheological studies also demonstrated the enhanced flowability and lower viscosity of the grafted material in comparison to the plasticized cellulose acetate.Highlights Grafting maleic anhydride onto plasticized cellulose acetate by reactive extrusion. Detection of grafted maleic anhydride onto cellulose acetate through NMR analysis. High thermal stability of grafted materials. Significant reduction in viscosity of plasticized cellulose acetate after grafting

Reactive extrusion of post‐irradiated poly(ethylene terephthalate) to improve the interfacial interactions in compounding with its immiscible polyethylene blends

AbstractThe aggregation of plastic waste results in immiscible polymer blends with inferior properties. This study explores the application of irradiation technology on polymer processing for its potential to increase the compatibility of immiscible polymer blends composed of poly(ethylene terephthalate) (PET) and linear low‐density polyethylene (LLDPE). When PET is radiated, it undergoes chain‐scission reactions resulting in the formation of free radicals. The extended lifespan of these free radicals in post‐irradiated PET provides an opportunity for inducing interface reactions with LLDPE during compounding through reactive extrusion. PET was irradiated with up to 50 and 200 kGy irradiation absorbance doses of gamma irradiation and then compounded with LLDPE in a twin‐screw extruder at three blend compositions. Analysis of rheological, morphological, and mechanical properties demonstrates the compatibility improvement in this immiscible polymer blend attributed to irradiation‐induced free radical interface reactions using post‐irradiated PET up to 50 kGy to conduct the reactive extrusion process.Highlights Reactive extrusion process with post‐irradiated PET. Formation of interface reactions. Improving the compatibility of immiscible polymer blend.

A review of polymer surface modification by cold plasmas toward bulk functionalization

AbstractPlasma surface modification of polymers is a well‐established method applied to increase the surface energy of these materials, where the capacity of cold plasmas to generate free radicals and functionalize the surface with polar groups is widely reported in the literature. This article provides a comprehensive literature review on plasma surface treatment, plasma‐induced grafting, and plasma polymerization, evaluating how these techniques can be applied to modify the bulk properties of polymers. A novel process of plasma‐induced polymer bulk functionalization in the melt state is introduced, where an atmospheric pressure plasma jet could be applied to a continuous reactive extrusion process, enhancing the production of graft copolymers for compatibilization of polymeric blends and fiber composites.

Detection of compatibilizer efficiency in conductive polymer blends by impedance spectroscopy: Microstructure evaluation approach

AbstractA novel approach of electrical impedance spectroscopy (EIS) is proposed to investigate the role of a compatibilizer on nanoparticle distribution in polymer blends with a co‐continuous morphology. Polypropylene/poly(ethylene‐co‐vinyl acetate) PP/EVA blends containing 3 vol% carbon nanotubes (CNT) with varying contents of polypropylene‐grafted‐ maleic anhydride (PP‐g‐MA) as compatibilizer were directly melt mixed. Microscopy, rheology, and thermodynamic analyses confirmed the distribution of CNTs in PP, EVA, and their interface. The EIS behavior of the blend nanocomposites was remarkably changed due to the formation of interphase by PP‐g‐MA/CNT. It was found that as the efficiency of compatibilizer increases the frequency dependency of the impedance diminishes showing a significant shift in the frequency cutoff from 104 Hz to 5 × 105 Hz. The EIS results also showed that compatibilizer can affect the loss factor. Incorporating 5 vol% or 10 vol% of the compatibilizer slightly reduced the loss factor, but a considerable reduction was observed at 20 vol% at which a conductive continuous interphase of compatibilizer formed at the interface. Moreover, the presence of compatibilizer led to a remarkable increase in dielectric constant by four orders of magnitude. EIS can effectively and comfortably trace the performance of a compatibilizer in a conductive polymer blend nanocomposite.Highlights EIS measurements describe microstructure of conductive polymer blend. EIS detects morphology development of a compatibilizer at varying contents. Migration of compatibilizer intensifies the Nyquist diameter decrement. Compatibilizer decreases dielectric relaxation time.

Patchy stereocomplex micelles as efficient compatibilizers for polymer blends

Patchy spherical micelles prepared via stereocomplex-driven self-assembly are applied as efficient compatibilizers for highly immiscible polystyrene/poly(tert-butyl methacrylate) blends.

Ca-bentonite/polymer blends to compose GCLs for effective containment of mining leachates

This study investigates the swelling potential of blends of a Brazilian sodium-activated calcium bentonite with linear structure polymers and a cross-linked structure polymer in contact with aggressive mining solutions (sodium hydroxide, calcium chloride, simulated bauxite liquor, copper tailing and gold tailing leachates). Results showed that the polymer addition contributed to the swelling of the bentonite under aggressive solutions. The effectiveness of the polymers varied with the permeant liquid and concentration. Sodium Polyacrylate and Carboxymethyl Cellulose proved the most effectiveness in bentonite swelling capacity. Research presents valuable insights into the chemical compatibility of bentonitepolymer blends when exposed to aggressive liquids.

Methylation of softwood and hardwood kraft lignins with chloromethane.

Methylation is a well-established means of enhancing the thermal stability, improving the compatibility in polymer blends, and lowering the glass-transition temperature of lignins. This process normally involves reagents that are costly, associated with poor atom economy and/or highly toxic. Herein, we report the methylation of softwood and hardwood kraft lignins using chloromethane in alkaline aqueous media. This reaction proceeds in high yields at 90-110 °C under moderate pressure (40 psi) while generating environmentally benign sodium chloride and water as by-products.

Alkali Activation of Clay and Water Potabilization Sludge Binary Blends: Influence of Composition and Curing Conditions

This work aims to evaluate the compatibility and features of alkali-activated blends obtained by replacing carbonate-rich illitic clay with either untreated or heat-treated water potabilization sludge (WPS). The experimental setting was created looking towards producing environmentally friendly solutions such as precursors that are sourced from the same territory, room-temperature curing in realistic environmental conditions, and activation exclusively with sodium hydroxide (NaOH) solutions. A multi-analytical characterization of the blends using X-ray powder diffraction (XRPD), an optical microscope (OM), a scanning electron microscope (SEM) equipped with an energy dispersive spectrometer (EDX), and a mechanical test demonstrated that up 75% of calcinated sludge and 25% of uncalcinated sludge could be successfully incorporated into the clay-based blends, offering a valuable alternative to landfill disposal of WPS. The matrices’ features were affected both by the amount of sludge in the blends and by the environmental conditions curing. since mineralogical investigations, OM and SEM observations showed the formation of secondary crystalline phases, mainly zeolitesin addition to amorphous gel. The mechanical strength results reached values between ~3 and 9 MPa, suggesting the possible use of the investigated alkali-activated blends for the formulation of precast building materials. Furthermore, to assure the replication of these alkali-activated blends, uncontrolled (T °C and RH%) curing does not appear to be the most appropriate solution. The study demonstrated that WPS, traditionally destined for landfill, could be a resource for the production of alkaline-activated materials by partially replacing unrenewable raw materials. thus resulting in the creation of eco-sustainable and economic processes as WPSare a widely and locally available industrial byproduct. However, a better control of mix designs and curing conditions is necessary for the upscaling of the here investigated blends.

Does a Compatibilizer Enhance the Properties of Carbon Fiber-Reinforced Composites?

We have evaluated the effectiveness of compatibilizers in blends and composites produced using a solvent manufacturing process. The compatibilizers were two different types of polyethylene (linear low-density and high-density) grafted with maleic anhydride (MAH) and a highly functionalized, epoxy-based compatibilizer with the tradename Joncryl. The selected material combinations were an ultra-high-molecular-weight polyethylene (UHMWPE) with MAH-based materials as compatibilizers and a polyphenylene sulfide plus polytetrafluoroethylene (PPS-PTFE) polymer blend with an epoxy-based compatibilizer. The findings revealed that while the compatibilizers consistently enhanced the properties, such as the impact strength and hardness of PPS-based compositions, their utility is constrained to less complex compositions, such as fibrous-reinforced PPS or PPS-PTFE polymer blends. For fibrous-reinforced PPS-PTFE composites, the improvement in performance does not justify the presence of compatibilizers. In contrast, for UHMWPE compositions, compatibilizers demonstrated negligible or even detrimental effects, particularly in reinforced UHMWPE. Overall, the epoxy-based compatibilizer Joncryl stands out as the only effective option for enhancing mechanical performance. Thermal and chemical characterization indicated that the compatibilizers function as chain extenders and enhance the fiber-matrix interface in PPS-based compositions, while they remain inactive in UHMWPE-based compositions. Ultimately, the incompatibility of the compatibilizers with certain aspects of the manufacturing method and the inconsistent integration with the polymer are the main reasons for their ineffectiveness in UHMWPE compositions.

Improved physical, thermal, and biological properties of green synthesized Ag-containing nanocomposites of a novel chitosan-based blend

Different material compositions are being prepared to improve the physiochemical properties of chitosan biopolymer and thus to create new areas of use. This study presents new chitosan(CS)-based products based on synthetic polymers and biosynthesized AgNPs, prioritizing environmentally friendly synthesis methods. Methacrylate-based functional CP copolymer was prepared by the free radical polymerization method. Thanks to the amide, ester groups, and fluorine atoms in the side branch of the CP, a compatible polymer blend (CS-CP) was prepared by the environmentally friendly hydrothermal method through hydrogen bonds with CS. Again, with green synthesis applications, AgNPs were prepared from Prunus spinosa extract by hydrothermal method, and new nanocomposites were produced by adding CS-CPs at different weight ratios. The initial decomposition temperature of 245 °C, which indicates the thermal stability of CS-CP as determined by TGA, was increased to 268 °C with the addition of 7 % AgNPs. Adding CP to CS lowered the glass transition temperature, and this trend continued in nanocomposites with the addition of AgNPs. When CP was blended with CS, the oxidative stress index of CS increased from 18.26 AU to 65.45 AU. It was determined that this oxidative effect increased up to 181 AU when AgNPs were added. Thanks to this feature of the produced nanocomposites, it was found that the MIC (100–250 µg/mL for E. coli, 250–500 µg/mL for S. aureus and for 500–1000 µg/mL C. Albicans) values of CS against microorganisms decreased, and the antimicrobial activity increased. In addition, in studies with cancer (A549 and G361) cells, it was determined that even at low (25 µg/mL) doses, nanocomposites that included 5 % and 7 % AgNPs in their formula had anticarcinogenic activity. Further studies on biocompatibility may be recommended to confirm possible commercial benefits from the materials produced in future research.

Evaluation of Thermal Decomposition Kinetics of Poly (Lactic Acid)/Ethylene Elastomer (EE) Blends.

The influences of ethylene-based elastomer (EE) and the compatibilizer agent ethylene-butyl acrylate-glycidyl methacrylate (EBAGMA) on the thermal degradation of PLA/EE blends were evaluated by the thermal degradation kinetics and thermodynamic parameters using thermogravimetry. The presence of EE and EBAGMA synergistically improved the PLA thermal stability. The temperature of 10% of mass loss (T10%) of PLA was around 365 °C, while in the compatibilized PLA/EE blend, this property increased to 370 °C. The PLA average activation energy (Ea¯) reduced in the PLA/EE blend (from 96 kJ/mol to 78 kJ/mol), while the presence of EBAGMA in the PLA/EE blend increased the Ea¯ due to a better blend compatibilization. The solid-state thermal degradation of the PLA and PLA/EE blends was classified as a D-type degradation mechanism. In general, the addition of EE increased the thermodynamic parameters when compared to PLA and the compatibilized blend due to the increase in the collision rate between the components over the thermal decomposition.

Design of Copolymer‐Based Blend Compatibilizers for Mixed Plastic Recycling

AbstractMixed plastic waste recycling represents a significant challenge as the phase separation of different components dictates downgraded performance. Polymer‐based compatibilizers can offer a promising solution to address this issue, through effectively reducing surface tension and increasing interfacial strength between distinct components to result in improved mechanical and thermal properties of recycled products. This perspective provides an overview of the fundamental concepts for the rational design of copolymer blend compatibilizers and discusses their recent advances, including both preformed and in situ generated systems. Impacts of key material parameters of compatibilizers, such as chain topology, chemical composition, and block sequence on their performance of remediating mixed plastics are discussed. Additionally, reactive compatibilization strategies are also introduced, including in situ formation of polymers, installing functional groups on mixed plastics, and employing dual compatibilization strategies. Looking forward, there are many research and technology opportunities in this area, especially for enabling the use of blend compatibilizers to practically address mixed plastic wastes at scale. Specifically, future compatibilizer design and application should provide strong competitiveness in both cost and energy savings, and carbon emission reduction. Together, the development of blend compatibilizers is an important step in establishing plastic circular economy and creating a more sustainable future.