Compatibility Of Blends Research Articles

IMPROVING THE PROPERTIES OF NR/NBR BLEND BY INTRODUCING INTERFACIAL CROSSLINKS USING BISMALEIMIDE DURING THE INITIAL PHASE OF ACCELERATED SULFUR CURING

ABSTRACT To develop a technologically compatible blend of NR and NBR is always a challenge due to their polarity mismatch. As a result, the physico-mechanical properties of their blends are generally poor. To address this issue, an attempt was made to increase the uniform distribution of crosslinks across the blend phases at the time of molding at 170°C. A cure composition consisting of sulfur (S) and a delayed action accelerator (N-cyclohexyl-2-benzothiazole sulfenamide [CBS]) has been designed to co-crosslink both phases of the blend simultaneously. The tensile properties, particularly the tensile strength (TS) of the blend cured by this method, were superior (∼371% greater) than the TS of the blend cured using a combination of S/CBS and an ultrafast accelerator (tetramethylthiuram disulfide [TMTD]). A bifunctional maleimide (Maleide F) was also used in conjunction with S/CBS in the curing recipe to further improve the distribution of sulfidic crosslinks by reducing the interfacial tension between the NR and NBR phases via Alder-ene reaction.

Efficiency of Polymer-silica Blends in the Microencapsulation of Yellow Fever Virus Vaccine

The currently available yellow fever vaccines are thermally unstable and involve huge costs during preservation and administration. Microencapsulation with thermally stable coating materials is considered as a means of protecting yellow fever vaccines from thermal degradation. Silica nanoparticles have thermal stabilizing abilities but do not possess film forming properties. It is proposed that polymer-silica blends might be a good coating material for microencapsulation. This study is aimed at investigating the compatibility and efficiency of blends of selected polymers with silicon obtained from rice husk ash (RHA) in microencapsulating yellow fever virus vaccine. The encapsulated yellow fever vaccine was characterised by FTIR and SEM-EDX spectroscopy, and the vaccine encapsulation efficiency was determined. FTIR spectra of the individual components and final encapsulated vaccine showed good chemical compatibility of all the ingredients. SEM studies of the products revealed uneven and rough surfaces with shrinkages. The vaccine encapsulation efficiency was 66.7%. Altogether, these results suggest that polymer-RHA silica blend can be used in microencapsulating yellow fever virus vaccine.

IMPROVING THE PROPERTIES OF A POLY (ACRYLONITRILE-CO-BUTADIENE)/NATURAL RUBBER BLEND BY INTRODUCING INTERFACIAL CROSSLINKS USING BISMALEIMIDE DURING THE INITIAL PHASE OF ACCELERATED SULFUR CURING

ABSTRACT To develop a technologically compatible blend of natural rubber (NR) and acrylonitrile-co-butadiene rubber (NBR) is always a challenge due to their polarity mismatch. As a result, the physico-mechanical properties of their blends will be generally poor. To address this issue, an attempt was made to increase the uniform distribution of crosslinks across the blend phases at the time of molding at 170 °C. A cure composition consisting of sulfur (S) and a delayed-action accelerator (N-cyclohexyl-2-benzothiazole sulfenamide: CBS) has been designed to co-crosslink both phases of the blend simultaneously. The tensile properties, particularly the tensile strength (TS) of the blend cured by this method were superior (approximately 371% greater) than the TS of the blend cured using a combination of S/CBS and an ultrafast accelerator (Tetramethylthiuram disulfide, TMTD). A bifunctional maleimide (Maleide F) was also employed in conjunction with S/CBS in the curing recipe to further improve the distribution of sulfidic crosslinks by reducing the interfacial tension between the NR and NBR phases via Alder-ene reaction.

Enhancing compatibility and properties of polylactic acid/polystyrene (PLA/PS) bioblend for sustainable food packaging: Experimental and quantum computational insights

This study investigated the impact of incorporating maleic anhydride grafted styrene-ethylene-butylene-styrene (SEBS-g-MAH) at varying concentrations (2.5, 5.0, 7.5, and 10.0 wt%) into binary blends of polylactic acid (PLA) and polystyrene (PS) with a weight ratio of 75/25. The blends were prepared using melt mixing in an internal Brabender mixer, followed by compression molding. Various characterization techniques, including Fourier transform infrared spectroscopy (FTIR), thermogravimetric analyses (TGA), differential scanning calorimetry (DSC), tensile testing, surface hardness measurements, and scanning electron microscopy (SEM) were employed to evaluate the structural, thermo-mechanical, surface, and morphological properties of the blends. FTIR results indicated the presence of n-π interaction between PLA and PS polymers. However, the introduction of SEBS-g-MAH to the blends resulted in specific interactions. TGA investigations demonstrated that compatibilized blends exhibited more excellent stability at high temperatures than their non-compatible counterparts. The DSC data align with the mechanical tests, revealing that the addition of SEBS-g-MAH reduced the crystallinity of the blends. Tensile strength, Young's modulus, and surface hardness diminished with the addition of SEBS-g-MAH, although the elongation at break improved. SEM analysis of the PLA/PS blends illustrated that incorporating SEBS-g-MAH enhanced the PS phase's distribution throughout the PLA matrix. Furthermore, molecular dynamic simulations revealed a significant enhancement in binding interaction energies upon adding SEBS-g-MAH, increasing from 2037.972 kcal/mol to 2826.946 kcal/mol for the PLA-PS and PLA-PS (5) systems, respectively. Density of state (DOS) analysis indicated that SEBS-g-MAH played an intermediary role, promoting compatibility between PLA and PS. These findings suggest that SEBS-g-MAH can effectively be a compatibilizer for PLA-PS blends.

Compatibilization of polylactide/poly(butylene adipate-co-terephthalate) blends with epoxidized natural rubber as a reactive compatibilizer

In this study, the effectiveness of using epoxidized natural rubber (ENR) to compatibilize blend of polylactide (PLA) with poly(butylene adipate-co-terephthalate) (PBAT) has been examined. Interfacial interaction analysis revealed that ENR had higher affinity with PBAT. To achieve better compatibility, a two-step procedure was developed involving blending PLA with ENR first, followed by blending with PBAT. Graft copolymers consisting of PLA, ENR, and PBAT were formed through melt blending, resulting in improved compatibility of PLA blends with PBAT. As the ENR content increased, the dispersed PBAT phase exhibited a gradual reduction in particle size. After compatibilization, the blends showed significantly improved toughness. Ternary PLA/PBAT/ENR blend containing 2 wt% ENR exhibited a drastic increase in break strain, measuring at 589%. This was approximately 2.7 times greater than the break strain of the binary blend PLA/PBAT (221%). The mechanism for tensile toughening of the PLA/PBAT/ENR ternary blends was interfacial bonding cavitation-initiated matrix plastic deformation. Compatibilization of PLA/PBAT blends with ENR is with great promise as it doesn’t compromise the biobased carbon content and sustainability of the materials.

Rheological behavior of recycled poly(ethylene terephthalate) /poly(amide) 11 blends with chain extender

There has been a remarkable surge in global demand for plastics, resulting in a significant increase in the generation of plastic waste. This, in turn, has led to a growing environmental concern. One global study ranked Malaysia as the eighth highest contributor to marine plastic pollution. Among various strategies, mechanical recycling emerges as a practical, economically viable, and environmentally efficient method for repurposing plastic waste. Nonetheless, the challenge of hydrolytic and thermal degradation of polyester macromolecules complicates the production of blends containing poly(ethylene terephthalate) (PET). An innovative solution to the plastic waste problem lies in leveraging polymer blends sourced from these waste materials, offering a potential remedy to recycling complexities. Blending of PET and poly(amide) 11 (PA11), a bio-derived polymer has demonstrated enhanced toughness and barrier properties for PET. Joncryl has been found to be an efficient chain extender as well as compatibilizer for other polymer blends. This paper focus on the effects of various content of Joncryl ADR 4468 (0,2,4 phr) as chain extender for recycled poly(ethylene terephthalate) /poly(amide) 11 (rPETPA11) blends on rheological behavior. The rPETPA11 ratio is fixed at 80:20 based on prior research. Capillary rheometry was employed to determine the rheological behavior and thermal stability of the blends at 280 °C. The presence of 2 and 4 phr Joncryl results in increased apparent viscosity of the rPETPA11 blends. Notably, the apparent viscosity remains stable for 45 min with the addition of 2 and 4 phr Joncryl. The assessment of thermal stability should be extended to further evaluate the effects of the chain extender on the degradation kinetics of rPETPA11 blends.

Poly(ethylene terephthalate)‐polyethylene block copolymer architecture effects on interfacial adhesion and blend compatibilization

AbstractIn this study, poly(ethylene terephthalate)‐block‐polyethylene (PET‐PE) multiblock copolymers (MBCPs) with block molar masses of ~4 or 7 kg mol−1 and either alternating or random block sequencing, and a PE‐PET‐PE triblock copolymer (TBCP) of comparable total molar mass, were synthesized. To explore the effect of molecular architecture on compatibilization, both MBCPs and TBCPs were blended into 80/20 wt/wt mixtures of PET/linear low‐density PE (LLDPE). Compatibilization was remarkably efficient for all MBCP types, with the addition of 0.2 wt% yielding blends nearly as tough as PET homopolymer. Addition of MBCP also significantly decreases LLDPE dispersed phase sizes compared to PET/LLDPE neat blends, as much as 80% in as‐mixed blends and by a factor of 10 in post‐mixing thermally annealed samples. Conversely, the TBCP was less efficient at decreasing domain sizes of the blends and improving the mechanical properties, requiring loadings of 1 wt% to produce comparably tough blends. Peel tests of PET/BCP/LLDPE trilayer films showed that both MBCPs and TBCP all improve interfacial strength over a PET‐PE bilayer film by two orders of magnitude; however, when the BCPs were preloaded into LLDPE, only the MBCP containing films showed strong adhesion highlighting their potential utility as adhesive agents in multilayer films.

Enhancing crystallization, miscibility, and processability of bio‐based polybutylene succinate/polypropylene blended composites via coffee husk reinforcement

AbstractMany studies have suggested that the interfacial compatibility in blends play an important role in determining the overall properties of the corresponding composites. This study investigated the effects of blend miscibility on the rheological, mechanical, and crystallization properties of polybutylene succinate (PBS)‐based composites reinforced with coffee husk (CH). The composites were fabricated using surface‐treated CH that was treated with a compatibilizer prior to composite fabrication. The results showed that the handling and processability of the composites improved after the surface treatment of CH. The surface treatment helped to achieve miscibility in polymer blends, and the dispersion of the surface‐treated CH in the PBS matrix was uniform. Moreover, the tensile strength and modulus of the compatibilized composites showed fourfold and twofold increases compared to neat PBS. The frequency‐dependent rheological test revealed increase in viscosity (>1000 times) and storage modulus with compatibilization and filler reinforcement. The degree of crystallinity of the PBS in the compatibilized composites reduced to about 10%. Furthermore, the compatibilized composites also demonstrated superior thermal stability than their corresponding non‐compatibilized composites.

Relative compatibility index for evaluation of the compatibility of crude oil blends

A new relative compatibility index is proposed to evaluate the compatibility of blends of crude oils. The approach considers the calculation of solvent power of individual crude oil and their blends, the critical solvent power for blends of crude oils with required amount of n-heptane when precipitation of asphaltenes begins, and a graphical comparison of both parameters (solvent power and critical solvent power) to determine the maximum proportion of crude oils in the blend to avoid incompatibility problems. The proposed method requires experimental data that are commonly available, such as specific gravity, TBP (True Boiling Point) distillation, and S-value (fuels stability determination according ASTM D 7157). Eight crude oils with a wide range of API (American Petroleum Institute) gravity (10–52°) were used to validate the method. It was demonstrated that the proposed approach accurately predicts the compatibility of blends of crude oils, and that relative compatibility index is an effective parameter to define appropriate amounts of crude oils to avoid asphaltenes precipitation during blending.

Preparation of thermoplastic polyurethane blend foams with controlled hydrophobicity via vapor induced phase separation

AbstractOil–water separation has attained great attention due to recent concern in environmental safety. Porous material from tailored engineering is the best candidate to selectively adsorb oil from water. Among the various porous materials, polymer based adsorbent has several advantages over others, in terms of controllable porosity and functionality. Here, we propose thermoplastic polyurethane (TPU) based blend foam through vapor induced phase separation method as a potential candidate for oil–water separation. In order to adjust hydrophobicity and compatibility of TPU blend, PDMS‐based TPU (Si‐TPU) is designed and synthesized to be blended with commercialized TPU. Si‐TPU with tailored weight ratio (PDMS/PTHF = 4/6) in synthetic level make it possible to achieve both of demanded hydrophobicity (the water contact angle increased from 85.19 ± 1.83° to 121.15 ± 3.79° after adding Si‐TPU) and controlling compatibility with CTPU during VIPS foaming. Thus, these well‐designed Si‐TPU can be utilized in various fields such as improving compatibility of polymer blend, adsorption efficiency of oil, and smart filtration, and so forth.

Molecular Dynamics Simulation in Compatibility and Mechanical Properties of Chloroprene Rubber/Polyurethane Blends

AbstractFive simulation models of chloroprene rubber (CR)/polyurethane (PU) with different composition ratios (9/1, 8/2, 7/3, 6/4, 5/5) are constructed and simulated using molecular dynamics (MD) simulation. The effects of PU content on blend compatibility and mechanical properties are investigated using solubility parameters, the Flory–Huggins interaction parameter, binding energy, glass transition temperature, and the radial distribution function. The objectives of this study are to develop a computational model based on MD techniques to investigate the compatibility and mechanical properties of CR/PU blends. The results of the solubility parameter indicated that PU has good miscibility with CR. The analysis of interaction parameters, binding energy, glass transition temperature, and radial distribution function show that CR/PU blends with mass ratios of 9/1, 8/2, and 7/3 have good compatibility. Moreover, the analyses of binding energy, pair correlation function, and radial distribution function reveal the reasons for the variation in mechanical properties of the blend systems. Additionally, the correctness of the calculation model and the results are verified by experimental tests and analyses.

Compatibilization of immiscible polymer blends by reactive polymer grafted graphene with interfacial crosslinking

AbstractWe investigate reactive compatibilization by applying two multifunctional polymers grafted on a graphene surface, which leads to crosslinked interphase at immiscible polymer blends. Reactive compatibilizer‐grafted graphene (RCG) nanoparticles were synthesized through esterification and amidation reactions between oxidative groups of graphene oxide and reactive multifunctional groups of polymers. Polymer blends of polyisoprene (PI) and polydimethysiloxane (PDMS) with PI:PDMS ratio of 30:70 or 70:30 and RCG nanoparticle loadings from 0.1 and 1 wt% were evaluated by optical microscopy and rheometry. The results indicated that the blend with 0.1 wt% RCG showed unusual characteristics including nonspherical and bridged droplets, while those containing 1 wt% RCG showed usual droplet‐matrix morphology. The rheological results are also asymmetric: the blend with 0.1 wt% RCG displayed gel‐like behavior in the dynamic oscillatory tests, high viscosity, slow interfacial relaxation during startup shear flow, and divergence in the transient stress response due to coalesced and bridged droplets. However, the latter blend containing 1 wt% RCG reveals liquid‐like behavior, low viscosity, and convergence in the transient stress response due to stabilized droplet‐matrix morphology. Overall, it was suggested that these asymmetries are attributable to interfacial crosslinked interphase formed through an in‐situ reaction between multifunctional polymers grafted on graphene sheets.

Molecular Mechanism of Plasticizer Exudation from Polyvinyl Chloride

Plasticizers improve polymer material flexibility and durability by lowering glass transition and cold flex temperatures. While many different classes of plasticizers have been synthesized and used in various applications, several classes have been phased out due to concerns over their safety. One of the main problems that hinder the development of a new generation of efficient and safe plasticizers is the plasticizers’ migration and exudation from polymer materials, which leads to a reduction of mechanical properties and premature degradation. Here, we employed multiscale molecular dynamics, validated by experiment, to investigate the molecular mechanism of exudation of an orthophthalate plasticizer (di-2-ethylhexyl phthalate (DEHP)), non-orthophthalate plasticizers (di-n-butyl terephthalate (DnBT) and di-2-ethylhexyl terephthalate (DEHT)), and their blends from polyvinyl chloride (PVC). The results suggest that DnBT acted as an intermediary between PVC and DEHT, improving the compatibility of the plasticizer blend and reducing the degree of exudation. Specifically, it was predicted that the 70:30 wt % DnBT–DEHT blend was on par with the DEHP control system. These results also suggest that plasticizer-PVC compatibility is a stronger determinant of plasticizer exudation than the plasticizer size, diffusivity, and viscosity, given that DnBT is a smaller, more mobile, faster-diffusing, and lower-viscosity plasticizer than DEHT. Overall, our results indicate that the most important parameters that control exudation were Hansen solubility and consequently Flory–Huggins interaction parameters.

Effects of sulfonation degree on compatibility and separation performance of polybenzimidazole (PBI)-sulfonated polyphenylenesulfone (sPPSU) blend membranes

The molecular compatibility between polybenzimidazole (PBI) and sulfonated polyphenylsulfone (sPPSU) and their blend membranes for herbicide removal in water reuse and for drug separation in organic solvent nanofiltration (OSN) have been investigated as a function of sulfonation degree in sPPSU. Flat sheet membranes cast from PBI-sPPSU blends with a mass ratio of 1:1 were prepared and then crosslinked by trimesoyl chloride (TMC) at room temperature. The blend made of PBI and 12.7 mol% sPPSU showed high compatibility based on the calculated enthalpy of mixing (ΔHm), measured dope viscosity, phase diagram, and single Tg. The TMC modified membrane cast from this composition also exhibited higher chemical resistance, mechanical stability, narrower pore size and pore size distribution, macrovoid-free structure and better separation performance. All fabricated membranes were evaluated using feeds containing tetracycline (MW = 444 Da) as a model drug in ethanol and pendimethalin (MW = 281.3 Da) as a model herbicide in water. The crosslinked PBI-12.7 mol% sPPSU (12.7C) membrane exhibited rejection of >96% against low-molecular-weight pendimethalin from water and tetracycline from ethanol. It also has the capability to separate mixed solutes, even with small molecular weights. This study illustrates the effectiveness of highly compatible polymer blends with the aid of one-step cross-linking modification for nanofiltration.

Thermogravimetric, Morphological and Infrared Analysis of Blends Involving Thermoplastic Starch and Poly(ethylene-co-methacrylic acid) and Its Ionomer Form.

This study focuses on the thermal properties and structural features of blends consisting of thermoplastic starch (TPS) and poly(ethylene-co-methacrylic acid) copolymer (EMAA) or its ionomer form (EMAA-54Na). The aim is to investigate how carboxylate functional groups of the ionomer form intervene in blends compatibility at the interface of the two materials and how this impacts their properties. Two series of blends (TPS/EMAA and TPS/EMAA-54Na) were produced with an internal mixer, with TPS compositions between 5 and 90 wt%. Thermogravimetry shows two main weight losses, indicating that TPS and the two copolymers are primarily immiscible. However, a small weight loss existing at intermediate degradation temperature between those of the two pristine components reveals specific interactions at the interface. At a mesoscale level, scanning electron microscopy confirmed thermogravimetry results and showed a two-phase domain morphology, with a phase inversion at around 80 wt% TPS, but also revealed a different surface appearance evolution between the two series. Fourier-transformed infrared spectroscopy analysis also revealed discrepancies in fingerprint between the two series of blends, analysed in terms of additional interactions in TPS/EMAA-54Na coming from the supplementary sodium neutralized carboxylate functions of the ionomer.

Precise role of zirconia to boost up the mechanical, thermal, viscoelastic, dielectric, and chemical resistance properties of natural rubber-nitrile rubber blend

Silica and other metal oxides have been emerged as potential substitutes of conventional carbon black (CB) to reinforce elastomeric materials. It not only steers clear of the ill-effects of CB such as issues like carcinogenicityand carbon footprint but they can impart rich thermal, optical, dielectric, and antimicrobial properties to the composites in addition to appreciable reinforcement. Silica is of special mention in this context while titania and zirconia to follow next. In this work, we report efficacy of zirconia towards property enhancement of a rubber blend comprised of non-polar natural rubber (NR) and polar nitrile rubber (NBR). Designed and controlled incorporation of zirconia in rubber matrix via an in-situ approach offers appreciable reinforcement to the composites. This is due to the fine dispersion of zirconia in elastomer matrix (SEM), efficient rubber-filler interaction (DMA) and increased crosslinking densities (swelling study). Analysis by atomic force microscopy (AFM) and differential scanning calorimetry (DSC) indicates that in-situ zirconia acts in favour of improved blend compatibility as well. All these factors offer notable impact on the other composite properties viz. improved thermal stability, enhanced flame retardancy and excellent chemical resistance to the blend composites. Additionally, dielectric properties become better upon incorporation of in-situ zirconia. The enhancement of composite properties becomes more prominent upon surface modification of in-situ zirconia by an organosilane Bis-(3-triethoxysilylpropyl) tetrasulfide (TESPT). Superiority of in-situ zirconia over externally filled zirconia has been established by a comparative analysis. Hence, current study offers valuable insights on the potential of in-situ zirconia as a substitute of CB to reinforce the rubber blends. The findings have important implications for the development of high performance elastomeric composites that can sustain in harsh service conditions.

Novel bionanocomposites of chitosan‐based blend containing LaB6: Thermal, dielectric, and biological properties

AbstractIn the presented study, a strategy that will offer alternative usage areas by strengthening the physicochemical properties of the green polymer chitosan (CS) is aimed. For this purpose, a compatible blend of CS (CS‐PFPAMA) with poly 2‐(4‐fluorophenyl)‐2‐oxoethyl‐2‐methylprop‐2‐enoate (PFPAMA), a methacrylate‐based synthetic polymer, was prepared by hydrothermal method. Miscibility and compatibility of the CS‐PFPAMA blend were confirmed by the single glass transition temperature (Tg) determined by differential scanning calorimetry (DSC). Then, lanthanum hexaboride (LaB6) nanoparticles (NPs) prepared by the chemical method were successfully added to the CS‐PFPAMA blend at different weight ratios by hydrothermal method. Morphological characterizations of CS‐PFPAMA blend and produced nanocomposites were performed with Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscope, energy‐dispersive X‐ray spectroscopy, and atomic force microscopy, and thermal characterizations were made with thermogravimetric analysis and DSC. The thermal stability and Tg values of the obtained CS‐PFPAMA blend and nanocomposites were lower than the values of the CS. However, LaB6 NPs increased the dielectric properties of the CS‐PFPAMA blend. Thus, the potential use of the produced nanocomposites in electronic devices may be in question. According to the results of antibiogram tests performed by the disk diffusion method, it was determined that nanocomposites showed a serious resistance against Escherichia coli and Staphylococcus aureus pathogens. In addition, both antioxidant and oxidant properties of nanocomposites showed values close to the reference material used. The determined biological properties indicate that the CS‐based nanocomposites can be used as biomaterials.

Compatibilization of Polymer Blends by Ionic Bonding

Chemically dissimilar polymers are rarely miscible due to a specific entropy of mixing that scales as 1/N, where N is the degree of polymerization. As a consequence, the compatibilization of immiscible polymer blends presents a major challenge to plastics recycling efforts. We demonstrate that when the chain ends of two highly immiscible polymers are functionalized with reacting acid and base groups, ionic junctions form in situ by proton transfer, leading to the stabilization of interfaces and the suppression of macroscopic phase separation. Due to the dynamic nature of proton transfer, the microstructure can be tuned via ionic bond energy (h) and segregation strength (χN). In this work, a library of ionically end-functionalized polystyrene (PS) and polydimethylsiloxane (PDMS) is used to demonstrate the importance of end-group acidity/basicity and molecular weight on compatibilization. Well-ordered lamellae result from blending polymers with strong acid and base units, while less ordered, more swollen microphases occur in systems with weak acid and base end groups or larger molar mass. Heating the ionic blends results in reverse proton transfer and destruction of the close-contact ion pairs. As a result, domains are swollen with the resulting unbonded homopolymers, which in sufficient amounts, leads to macrophase separation. Moreover, external salt ions screen the electrostatic attractions and disturb ionic compatibilization. The self-consistent field theory (SCFT) of this system reveals that the ionic interactions can be tuned to create a broad range of morphologies, from microphases to macrophases.

Investigation of the Effects of Chain Extender on Material Properties of PLA/PCL and PLA/PEG Blends: Comparative Study between Polycaprolactone and Polyethylene Glycol.

This study investigated the effect of the Joncryl concentration on the properties of polylactide/poly(ε-caprolactone) (PLA/PCL) and PLA/poly(ethylene glycol) (PEG) blends. The addition of Joncryl influenced the properties of both PLA-based blends. In the blend of PLA/PCL blends, the addition of Joncryl reduced the size of PCL droplets, which implies the compatibility of the two phases, while PLA/PEG blends showed a co-continuous type of morphology at 0.1% and 0.3 wt.% of Joncryl loading. The crystallinity of PCL and PEG was studied on both PLA/PCL and PLA/PEG blend systems. In both scenarios, the crystallinity of the blends decreased upon the addition of Joncryl. Thermal stabilities were shown to depend on the addition of Joncryl. The toughness increased when 0.5 wt.% of Joncryl was added to both systems. However, the stiffness of PLA/PCL decreased, while the stiffness of PLA/PEG increased with the increasing concentration of Joncryl. This study provides new insight into the effect of chain extenders on the compatibility of PLA-based blends.

Double percolation behavior through the preferential distribution of conductive black in polymer blends to boost electrical properties and EMI shielding effectiveness

The preferential distribution of the filler in the polymer blends leads to a lower percolation threshold in comparison to a single polymer matrix with random filler distribution. Poly(ethylene methyl acrylate) (EMA) and carboxylated acrylonitrile butadiene rubber (XNBR) composites of EMA-XNBR (EX) with a variable amount of conductive carbon black (Vulcan XC 72; VXC) has been prepared by conventional melt blending. These composites have superior electromagnetic interference (EMI) shielding effectiveness to attenuate the hazardous effects and save society from proliferating electromagnetic radiation. The suitable distribution of carbon black lowers the electrical percolation threshold of 12.5 phr by the formation of interconnected architecture following the two-step percolation phenomenon and results in an improved EMI SE of 33.5 dB. The morphological analysis demonstrates that the formation of a polymer-filler network of VXC in an EX technologically compatible blend increases the mechanical and thermal stability of composites by retaining their flexibility, which facilitates the application of EXV composites in techno-commercial fields.