Miscibility of polymethylmethacrylate and polyethyleneglycol blends in tetrahydrofuran

The miscibility of polymethylmethacrylate (PMMA) and polyethyleneglycol (PEG) blends in tetrahydrofuran (THF) has been investigated by viscosity, density, refractive index, and ultrasonic velocity studies. Various interaction parameters such as polymer–solvent and blend–solvent interaction parameters and heat of mixing have been calculated using the viscosity, density, and ultrasonic velocity data. The results indicated the existence of positive interactions in the blend polymer solutions and that they are miscible in THF in the entire composition range. The study also revealed that variation in the temperature does not affect the miscibility of PMMA and PEG blends in THF significantly. The presence of hydrogen bonding in the blends in the solid state has also been indicated by FTIR studies. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Miscibility studies on chitosan/hydroxypropylmethyl cellulose blend in solution by viscosity,ultrasonic velocity,density, and refractive index methods

The miscibility studies of chitosan (CHI)/hydroxypropylmethyl cellulose (HPMC) blend in buffer solution (0.1M acetic acid + 0.2M sodium acetate) were carried out by viscosity, ultrasonic velocity, density, and refractive index methods at 30, 40, and 50°C, respectively. Using viscosity data, the interaction parameter μ and α were computed. These values revealed that the blend is miscible when the CHI content is more than 50% in the blend. The obtained results were further confirmed by ultrasonic velocity, density, and refractive index study. And also the result revealed that the change in temperature has no significant effect on the miscibility of CHI/HPMC polymer blends. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2738–2742, 2006     

Miscibility study of cellulose acetate/carboxylated poly(vinyl chloride) blend in cyclohexanone by viscosity,ultrasonic velocity,refractive index,and polarizing microscopic methods

The viscosity, ultrasonic velocity, refractive index, and density of cellulose acetate/carboxylated poly(vinyl chloride) (CA/C‐PVC) blends in cyclohexanone, a common solvent, were measured at 30°C. After casting films of the blend for a 50:50 composition, polarizing micrographs were taken. Using the viscosity data, the interaction parameters were computed by employing two different equations. These values indicated that the CA/C‐PVC blend is miscible. This was confirmed by ultrasonic, refractive index, density, and polarizing microscopic methods. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 557–561, 2001     

Ultrasonic,refractometric, and viscosity studies of some polymer blends in solution

Miscibility studies of poly(vinyl pyrrolidone)–polystyrene and poly(vinyl pyrrolidone)–poly(methyl methacrylate) in mixed common solvent (dimethyl formamide + cyclohexanone) have been carried out in different percentages of the blend components. The ultrasonic velocity, viscosity, density, and refractive index have been measured at 30°C. The interaction parameters have been obtained using the viscosity data to probe the miscibility. The obtained results have been confirmed by the ultrasonic velocity, density, and refractive index. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 70: 1823–1827, 1998     

Immiscibility of Silicone Rubber and Polymethylmethacrylate

Polymer blends of silicone polymer with polymethylmethacrylate (PMMA) have been prepared by solution blending, and their miscibility has been investigated by using physical techniques like viscosity, refractive index, density and ultrasonic velocity for blend solutions at different percentages of the blend composition. All the measurements are made at 30°C. The results are discussed.     

Miscibility studies of epoxy/unsaturated polyester resin blend in chloroform by viscosity,ultrasonic velocity,and refractive index methods

Miscibility studies of blends of epoxy with unsaturated polyester resin in chloroform were carried out by viscosity, ultrasonic velocity, and refractive methods at 30°C. By using viscosity data, the interaction parameters were computed, which indicated that epoxy/unsaturated polyester resin blends were miscible. The miscibility was further confirmed by the ultrasonic velocity and refractive index methods. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2970–2972, 2003     

Miscibility studies of sodium alginate/poly(vinyl alcohol) blend in water by viscosity,ultrasonic, and refractive index methods

The miscibility of a sodium alginate/poly(vinyl alcohol) blend in water was studied by viscosity, ultrasonic velocity, and refractive index techniques at 30, 40, and 50°C. Using the viscosity data, interaction parameters μ and α were computed. These values revealed that the blend is miscible when the sodium alginate content is more than 50% in the blend. This was further confirmed by ultrasonic and refractive index methods. It was further observed that the temperature has only a marginal effect on the miscibility of this blend. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 33–39, 2003     

Miscibility of Polycarbonate/Polyvinylpyrrolidone and Polycarbonate/Polyethylene Oxide in Chloroform by Viscosity,Ultrasonic and Refractometric Methods

Abstract

Miscibility studies of polycarbonate/polyvinylpyrrolidone (PC/PVP) and polycarbonate/ polyethylene oxide (PC/PEO) in common solvent chloroform were carried out in different percentages of the blend compositions. The viscosity, ultrasonic velocity, refractive index and density were measured at 30[ddot]C. The interaction parameters were obtained using the viscosity data to probe the miscibility. The obtained results were confirmed by the ultrasonic velocity, density and refractive index measurements.     

Morphology and mechanical properties of thermoplastic elastomers from nylon-nitrile rubber blends

Nylon-nitrile rubber blends having different plastic-rubber component ratios (100/0, 80/20, 70/30, 60/40, 50/50, 40/60, 30/70, 20/80, and 0/100) were prepared by melt mixing technique in a Rheocord-90 at a temperature set at 180°C. The mixing characteristics of the blends have been analyzed from the rheographs. The morphology of the blend was studied using optical and electron microscopies, with special reference to the effect of blend ratio. The micrographs indicate a two-phase system where the component having lower proportions was found to disperse in the major continuous phase. A cocontinuous morphology was observed for 50/50 composition. Mechanical properties of the blends have been measured according to standard test methods. The effect of blend ratio on the mechanical properties like tensile strength, tear strength, elongation at break, stress-strain behavior, and hardness has been analyzed. The influence of the strain rate on the mechanical properties has also been analyzed. The mechanical properties were found to have a strong dependence on the amount of nylon in the blend. It is found that the blends with higher proportions of nylon have superior mechanical properties. The observed changes in mechanical properties are explained on the basis of the morphology of the blend. Various theoretical models such as Series, Parallel, Halpin-Tsai, and Coran's equations have been used to fit the experimental mechanical data. © 1996 John Wiley & Sons, Inc.     

Molecular simulation and experimental studies of the miscibility of polylactic acid/polyethylene glycol blends

Computer simulation and experiments were performed to investigate the miscibility of PLA/PEG blends with different PEG concentrations. Flory-Huggins interaction (χ) parameter used to predict the miscibility for the blends was estimated by molecular dynamic simulation of fully atomistic model. The calculated χ parameter and radial distribution function suggest that the PLA and PEG blends are likely miscible at low PEG concentrations (10–30 wt%), but they become apparently immiscible at higher PEG content (>50 wt%). This result is consistent with density distribution of PLA and PEG beads calculated from dissipative particle dynamics simulation of coarse-grained model. To support the computational results, experiments based on differential scanning calorimetry (DSC) and rheometry were also performed. The DSC thermograms of 90:10, 80:20, and 70:30 (wt/wt) of PLA/PEG blends showed a single glass transition and PLA melting peak, indicating PLA/PEG is miscible over this composition. In rheometry, frequency (ω) dependence of storage moduli (G′) at low frequencies for 75:25 and 70:30 blends indicate that these samples are near the phase separation point.     

Investigation on miscibility behaviors of elastin‐like polypentapeptide blends with polyvinyl alcohol in aqueous and solid state

The polypentapeptide of elastin, poly(GVGVP) has shown remarkable properties and have great potential for biomedical applications. To explore its applications further, the miscibility behaviors of poly(vinyl alcohol) (PVA)/poly(GVGVP) blends have been explored in a very broad composition range. The miscibility behaviors of these blends have been investigated in both solution and solid state using various analytical techniques, including ultrasonic velocity, density, refractive index (RI) and viscosity techniques at 25 °C. The results confirmed the miscibility of the blend up to 40% of the polypeptide. This was further supported by Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44624.     

Study on the Crystallization Kinetic and Characterization of Poly(lactic acid) and Poly(vinyl alcohol) Blends

In this study, poly(lactic acid) (PLA) and poly(vinyl alcohol) (PVA) blends, with PLA/PVA mass ratios of 100/0, 90/10, 80/20, 70/30, 60/40, 50/50, and 40/60, were prepared by means of the melt blending method. The result of torque measurements and thermal gravimtric analysis tests showed that the addition of PLA can decrease the melt viscosity of PVA and that the second degradation step of PVA nearly disappeared for the PLA₈₀/PVA₂₀ blend. The absorbance peaks of the carbonyl group and the hydroxyl group in the Fourier transform infrared spectra of PLA/PVA blends had significant shifts to lower wave numbers, indicating that there were interactions between these two groups. Combined with the result of the differential scanning calorimetry curves, this interaction would be favorable for improving miscibility. The X-ray diffraction patterns and the polarized light microscope (PLM) micrographs showed that PVA can serve as a nucleating agent to promote the crystallization of PLA in PLA/PVA blends. Moreover, the PLA₈₀/PVA₂₀ blend gave the highest growth rate of PLA spherulite.     

Miscibility study of chitosan/polyethylene glycol fumarate blends in dilute solutions

Solution miscibility of chitosan/polyethylene glycol fumarate blends dissolved in acetate buffer solution was investigated in different blend compositions by viscosity, density, and refractive index measurement techniques at 30, 40, and 50°C. In order to quantify the miscibility of the polymer pair, degree of miscibility was studied by means of two criteria known as interaction parameters i.e., μ and α. On the basis of the sign convention involved in these criteria, these values revealed that the blend solution was miscible when the chitosan content was more than 80% (w/w) of the composition. The results were confirmed by density, and refractive index measurements. Furthermore, the results showed that the miscibility window of chitosan/polyethylene glycol fumarate blends was independent with respect to the changes in solution temperature. Therefore, these results suggested due to intermolecular hydrogen‐bonding interaction between amino and hydroxy groups of chitosan and hydroxy groups of polyethylene glycol fumarate which play an important role in the formation of miscible phase. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

New smart conducting elastomer blends of Bi‐based superconductor ceramics nanoparticles reinforced natural rubber/low‐density polyethylene for double thermistors,antistatic protectors,and electromagnetic interference shielding effectiveness applications

A new conducting blend from natural rubber (NR), low‐density polyethylene (PE), and Bi‐based superconductor (BSCCO) nanoparticles was successfully formulated. Blends were prepared by means of an open two‐roll mill for five ratios (100/0, 90/10, 80/20, 70/30, and 60/40 NR/LDPE). The microstructures of the blends were examined in terms of scanning electron microscopy (SEM), bound rubber (BR), cross‐linking density (CLD), and Mooney viscosity (M₁₀₀). The mechanical properties like hardness (H) shore A, tensile strength (TS), and elongation at break (EB) of the blends were studied. The applicability of the blends as double thermistors, i.e., positive and negative coefficient of resistivity (PTCR/NTCR), was examined. The applicability of the blend for antistatic charge dissipation was also tested. Finally, electromagnetic interference response of conducting NR/PE‐filled BSCCO in the frequency range 1–12 GHz has been studied. Shielding effectiveness of the conducting blends in the microwave range 8–12 GHz shows an attenuation of 44–60 dB for PE ≤10 wt%. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers     

Miscibility studies of hydroxypropyl cellulose/poly(vinyl pyrrolidone) in dilute solutions and solid state

The miscibility of hydroxypropyl cellulose (HPC) and poly(vinyl pyrrolidone) (PVP) blends in aqueous solutions was studied using viscosity, ultrasonic velocity, and refractive index techniques at 30°C. The interaction parameters ΔB, μ, and α calculated from viscosity using Sun and Chee methods indicated the miscibility of this blend. This was further confirmed by ultrasonic and refractive index results. The HPC/PVP blend films are prepared by solution casting method and are analyzed by differential scanning calorimetry, X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopic techniques that confirmed the complete miscibility. This miscibility is due to the strong intermolecular H-bonding interactions between  OH groups of HPC and CO groups of PVP. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Thermal stability and aging characteristics of (natural rubber)/(waste ethylene‐propylene‐diene monomer terpolymer) blends

Comparative studies of the thermogravimetric analysis and thermo‐oxidative aging of (natural rubber)/(waste ethylene‐propylene‐diene monomer terpolymer) (NR/W‐EPDM) and (natural rubber)/(ethylene‐propylene‐diene monomer terpolymer) (NR/EPDM) blends were carried out. The blends were prepared at five different blend ratios (90/10, 80/20, 70/30, 60/40, and 50/50) on a two‐roll mill. As the pure EPDM or W‐EPDM content in the blends increased, their thermal stability also increased. The thermo‐oxidative aging of these blends was done at 100°C for 48 h. Afterwards, the NR/EPDM blends exhibited better retention of properties than the NR/W‐EPDM blends. Crosslink density measurements of the blends after thermal aging indicated that higher crosslink density was obtained from a higher content of EPDM or W‐EPDM, a result which might be due to the high rate of radical termination leading to crosslinks in the bulk of the polymer. J. VINYL ADDIT. TECHNOL., 20:99–107, 2014. © 2014 Society of Plastics Engineers     

Interpenetrating polymer network structured thermosets prepared from epoxidized soybean oil/diglycidyl ether of bisphenol A

Epoxidized soybean oil (ESO)/diglycidyl ether of bisphenol A (DGEBA) in various blend ratios (i.e. 100/0, 90/10, 80/20, 70/30, 60/40, 50/50) was thermally cured using methylhexahydrophthalic anhydride in the presence of 2‐ethyl‐4‐methylimidazole catalyst. The tensile properties and fracture toughness of the ESO/DGEBA thermoset blends were determined. Thermal properties of the blends were characterized using dynamic mechanical analysis, differential scanning calorimetry and thermogravimetric analysis. Blending of ESO and DGEBA gave synergistic effects on the modulus, strength, glass transition temperature and thermal stability. However, the fracture toughness and elongation at break of ESO/DGEBA blends are lower than those of ESO, as expected. The enhancement in certain mechanical and thermal properties of ESO/DGEBA can be associated with the crosslink density, gel content and possible interpenetrating network of the resulting thermoset blends. © 2013 Society of Chemical Industry     

Dynamic mechanical and morphological studies on the compatibility of plasticized PVC/thermoplastic polyurethane blends

In this work, the compatibility of blends of plasticized poly(vinyl chloride) (p‐PVC) and thermoplastic polyurethane (TPU) was investigated using a dynamic mechanical analyzer and scanning electron microscopy. Two kinds of TPU with different ratios of hard to soft segments, i.e., TPU90 and TPU70 were compared. p‐PVC/TPU90 and p‐PVC/TPU70 blends with variable weight ratios (100/0, 90/10, 80/20, 70/30, 60/40, 50/50, 0/100) were prepared by melt blending. PVC was plasticized with 40 phr of dioctyl phthalate. It was found that TPU with a lower hard segment (i.e., TPU70) is more compatible with plasticized PVC than TPU with a higher hard segment (i.e., TPU90) in over the composition ranges examined. It was concluded that the compatibility of plasticized PVC and TPU are dependent on the ratio of hard to soft segments in TPU. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 415–422, 1999     

Effect of blend ratio on cure characteristics,tensile properties,thermal and swelling properties of mica‐filled (ethylene‐propylene‐diene monomer)/(recycled ethylene‐propylene‐diene monomer) (EPDM/r‐EPDM) blends

(Ethylene‐propylene‐diene monomer)/(recycled ethylene‐propylene‐diene monomer) (EPDM/r‐EPDM) blends filled with constant mica loading were compounded at various blends ratios (i.e., 90/10, 80/20, 70/30, 60/40, and 50/50). Results indicated that scorch time decreased with increasing r‐EPDM content, whereas curing time, minimum torque, and maximum torque show the opposite trend. The tensile strength, stress at 100% elongation, and elongation at break value increased with increasing r‐EPDM loading in the blend systems and the optimum properties occurred at 70/30 EPDM/r‐EPDM blends ratio. The thermal stability of EPDM/r‐EPDM blends increased with increasing r‐EPDM content in the blends but the swelling percentage showed the opposite trend with a greater addition of r‐EPDM content in the blends. J. VINYL ADDIT. TECHNOL., 21:1–6, 2015. © 2014 Society of Plastics Engineers     

Phase morphology of PP/COC blends

Phase morphology of polymer blends PP/COC, where PP is polypropylene and COC is a copolymer of ethene and norbornene, was characterized by means of scanning electron microscopy (SEM) and scanning transmission electron microscopy (STEM). PP/COC blends were prepared by injection molding and their morphology was studied for six different compositions (90/10, 80/20, 70/30, 60/40, 50/50, and 25/75 wt %). The intention was to improve PP properties by forming COC cocontinuous phase, which should impart to the PP matrix higher stiffness, yield stress, and barrier properties. Surprisingly enough, all studied blends were found to have fibrillar morphology. In the 90/10, 80/20, and 70/30 blends, the PP matrix contained fibers of COC, whose average diameter increased with increasing COC fraction. In the 60/40 blend, the COC component formed in the PP matrix both fibers and larger elongated entities with PP fibers inside. The 50/50 blend was formed by COC cocontinuous phase with PP fibers and PP cocontinuous phase with COC fibers. In the 25/75 blend, PP fibers were embedded in the COC matrix. In all blends, the fibers had an aspect ratio at least 20, were oriented in the injection direction, and acted as a reinforcing component, which was proven by stress–strain and creep measurements. According to the available literature, the fibrous morphology formed spontaneously in PP/COC is not common in polymer blends. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 253–259, 2004