Synthesis and evaluation of interaction parameters of synthetic elastin‐derived polypentapeptide with poly(vinylpyrrolidone) in solution and solid phase

The parent repeating sequence of elastin, poly(GVGVP) has been synthesized by solution phase method and characterized by 13C and ¹H‐NMR spectroscopy. The poly(GVGVP) and poly(vinyl pyrrolidone) (PVP) interactions have been examined in solution phase by the viscometric method at 24 °C. The interaction parameters such as α, β, µ, and Δ[η]_m indicated the miscible nature of poly(GVGVP)/PVP blends. Immiscibility occurred when the quantity of poly(GVGVP) is lesser than 60%. In the solid phase, Fourier transform infrared spectroscopic scrutiny of the thin films of poly(GVGVP)/PVP blends indicated the presence of strong intermolecular interaction such as hydrogen bonds linking the blend components. This result was further supported by glass transition temperature (T_g), scanning electron microscopic, and X‐ray diffraction studies. The blending of poly(GVGVP) with PVP may provide an opportunity to produce new materials for potential biomedical applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46699.     

Binary and ternary polymer blends containing poly(vinylidene chloride‐co‐acrylonitrile)

Poly(vinylidene chloride‐co‐acrylonitrile) (Saran F), poly(hydroxy ether of bisphenol A) (phenoxy), poly(styrene‐co‐acrylonitrile) (PSAN), and poly(vinyl phenol) (PVPh) all have the same characteristic: miscibility with atactic poly(methyl methacrylate) (aPMMA). However, the miscibility of Saran F with the other polymer (phenoxy, PSAN, or PVPh) is not guaranteed and was thus investigated. Saran F was found to be miscible only with PSAN but not miscible with phenoxy and PVPh. Because Saran F and PVPh are not miscible, although they are both miscible with aPMMA, aPMMA can thus be used as a potential cosolvent to homogenize PVPh/Saran F. The second part of this report focused on the miscibility of a ternary blend consisting of Saran F, PVPh, and aPMMA to investigate the cosolvent effect of aPMMA. Factors affecting the miscibility were studied. The established phase diagram indicated that the ternary blends with high PVPh/Saran F weight ratio were found to be mostly immiscible. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3068–3073, 2004     

Rheological behaviour of suspensions prepared from plate‐shaped titanium dioxide particles in (hydroxypropyl) methylcellulose aqueous solution

Suspensions were prepared by homogeneously mixing titanium dioxide particles in (hydroxypropyl) methylcellulose (HPMC) aqueous solutions. Thin plate‐shaped particles were made from balloon materials crushed to pieces. The other three types of particles used as references were plate‐shaped samples surface‐modified with alumina, and two types of spherical particles of anatase and rutile forms. Plateau adsorption amounts of HPMC onto particles depended on their surface properties. Comparisons of rheological behaviour were carried out among the residual three samples except for the sample having the rutile form. Within the concentration range used, the viscosity values of suspensions were rather lower than that of HPMC aqueous solutions. The reason for such low values was attributed to the decrease of entanglements in the semi‐dilute regime and also to steric stabilization resulting from the formation of the HPMC adsorbed layer. The change of structural viscosity and its recovery were evaluated by observation of the decrease of viscosity and its recovery as an indicator. It was confirmed that suspensions of thin plate‐shaped particles had superior structural recovery performance. © 2002 Society of Chemical Industry     

Synthesis of poly[(2‐oxo‐1,3‐dioxolan‐4‐yl)methyl vinyl ether‐co‐N‐phenylmaleimide] and its miscibility in blends with styrene‐acrylonitrile or poly(vinyl chloride)

The aim of the study was to investigate the synthesis of a copolymer bearing cyclic carbonate and its miscibility with styrene/acrylonitrile copolymer (SAN) or poly(vinyl chloride) (PVC). (2‐Oxo‐1,3‐dioxolan‐4‐yl)methyl vinyl ether (OVE) as a monomer was synthesized from glycidyl vinyl ether and CO₂ using quaternary ammonium chloride salts as catalysts. The highest reaction rate was observed when tetraoctylammonium chloride (TOAC) was used as a catalyst. Even at the atmospheric pressure of CO₂, the yield of OVE using TOAC was above 80% after 6 h of reaction at 80°C. The copolymer of OVE and N‐phenylmaleimide (NPM) was prepared by radical copolymerization and was characterized by FTIR and ¹H‐NMR spectroscopies and differential scanning calorimetry (DSC). The monomer reactivity ratios were given as r₁ (OVE) = 0.53–0.57 and r₂ (NPM) = 2.23–2.24 in the copolymerization of OVE and NPM. The films of poly(OVE‐co‐NPM)/SAN and poly(OVE‐co‐NPM)/PVC blends were cast from N‐dimethylformamide. An optical clarity test and DSC analysis showed that poly(OVE‐co‐NPM)/SAN and poly(OVE‐co‐NPM)/PVC blends were both miscible over the whole composition range. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 1809–1815, 2000     

Polypropylene–clay blends compatibilized with MAH‐g‐POE

A series of new Polypropylene (PP)–clay blends, containing 5 wt % clay, were prepared by melt compounding with maleic anhydride grafted poly(ethylene‐co‐octene) (MAH‐g‐POE) as the compatibilizer by varying its content from 0 to 20 wt %. The effect of MAH‐g‐POE on the PP–clay miscibility was examined by X‐ray diffraction (XRD), scanning electronic microscope (SEM) observation, differential scanning calorimeter (DSC) analysis, dynamic mechanical thermal analysis (DMTA), and rheological testing in sequence. The results showed that the addition of MAH‐g‐POE could improve the dispersion of clay layers in PP matrix and promoted the interaction between PP molecules and clay layers. At 10 wt % MAH‐g‐POE, the PP–clay blend exhibited a highest value of Tc,onset and Tg as well as a biggest melt storage modulus (G′), indicating the greatest PP–clay interaction. On the other hand, improved toughness and stiffness coexisted in blends with 5–10 wt % loading of MAH‐g‐POE. In view of SEM and DMTA observations, MAH‐g‐POE was well miscible with the PP matrix, even with the concentration up to 20 wt %. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 2558–2564, 2006     

Miscibility,morphology and tensile properties of vinyl chloride polymer and poly(ε‐caprolactone) blends

The miscibility, morphology and tensile properties of three blend systems of poly(ε‐caprolactone) (PCL) with poly(vinyl chloride) (PVC) and with two chlorinated PVCs (CPVCs) with different chlorine contents (63 wt% and 67 wt% of Cl) have been studied. Based on the shifts of single glass transition temperature, the Gordon–Taylor K parameter is calculated as a measurement of interaction strength between PCL and (C)PVCs. Higher K values are found for blends of (C)PVCs with higher chlorine content, together with the interaction χ parameters estimated from the melting point depression results. The morphology observed with polarized light microscopy shows that spherulites exist in blends rich in PCL (≥50 wt%) only. Wide angle X‐ray diffraction studies indicate that the crystal structure of PCL is independent of the Cl content of (C)PVCs. The tensile properties of various blends exhibit a minimum as the PCL content increases. The elongation at break increases with increasing PCL content. © 2000 Society of Chemical Industry     

Blends of polypropylene with poly(cis‐butadiene) rubber. II. Small‐angle X‐ray scattering studies of the phase structure of immiscible blends of polypropylene with poly(cis‐butadiene) rubber

Pressed films of the blends of polypropylene (PP) with poly(cis‐butadiene) rubber (PcBR) were studied by IR spectra, small‐angle X‐ray scattering, and scanning electron microscopy. The problem of the interaction between different macromolecules in the blends of PP/PcBR is discussed by melt‐mixing at a temperature of 210°C using IR. X‐ray scattering from the relation of the phase was analyzed using Porod's law, and the interface layer thickness was calculated. The immiscibility of the blends of PP/PcBR was proved. The structure parameters, the correlation distance a_c, average chord lengths l?, and radius of gyration R?_g were obtained by the Debye–Buech statistical theory of scattering. Porod's index was calculated and the shape of the dispersed phase is discussed in relation to Porod's index in the blends. The morphology and structure of the blends were investigated by scanning electron microscopy. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2088–2094, 2002     

Binary blends based on poly(N‐isopropylacrylamide): Miscibility studies with PVA,PVP, and PAA

Blends of poly(vinyl alcohol) (PVA), poly(acrylic acid), (PAA), and poly(vinyl pyrrolidone) (PVP), with poly(N‐isopropylacrylamide) (PNIPAM), were prepared by casting from aqueous solutions. Mechanical properties of PNIPAM/PVA blends were analyzed by stress–strain tests. Differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) were employed to analyze the miscibility between the polymeric pairs. The results revealed that PNIPAM is not miscible with PVA and PVP in the whole range of composition. On the other hand, PNIPAM interacts strongly with PAA forming interpolymer complex due to the formation of cooperative hydrogen bonds. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 743–748, 2004     

Miscibility of polymer blends of poly(styrene‐co‐4‐hydroxystyrene) with bisphenol‐A polycarbonate

The miscibility of blends of bisphenol‐A polycarbonate (BAPC) and tetramethyl bisphenol‐A polycarbonate (TMPC) with copolymers of poly(styrene‐co‐4‐hydroxystyrene) (PSHS) was studied in this work. It has been demonstrated that BAPC is miscible with PSHS over a region of approximately 45–75 mol % hydroxyl groups in the copolymer. TMPC has a wider miscible window than BAPC when blended with PSHS. The blend miscibility was considered to be driven by the intermolecular attractive interactions between the hydroxyl groups of the PSHS and the π electrons of the aromatic rings of both polycarbonates (PCs). As the FTIR measurements showed, after blending of BAPC with PSHS, there is no visible shift of the carbonyl band of BAPC at 1774 cm⁻¹, whereas the stretching frequency of the free hydroxyl groups of the copoly‐ mers at 3523 cm⁻¹ disappeared. The large positive values of the segment interaction energy density parameter B_st‐HS calculated from the group contribution approach indicated that the intramolecular repulsive interaction may also have played a role in the promotion of the blend miscibility. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 639–646, 1999     

Spectroscopic and electrochemical studies on block‐polymer/PMMA blend based composite polymer electrolytes

Poly(methylmethacrylate)(PMMA)/oxymethylene‐linked polyoxyethylene multi‐block polymer(Om‐POE_n, where n represents number of unit  CH₂CH₂O ) blend based composite electrolyte films containing different lithium salt concentration and nanofillers' content are prepared using solvent evaporation technique. The interaction of polymer–salt complex has been confirmed using FTIR spectral studies. The figuration of CPE was studied by XRD. Ionic conductivity and thermal behavior of the CPEs were studied with various salt concentrations, temperature, and nanofillers' content. The surface structure of the CPE is also investigated using scanning electron microscopy. The high room temperature ionic conductivity, transmittivity in the visible region, and thermal stability make these CPEs potential candidates as solid‐like electrolytes for electrochemical devices. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

Synthesis and swelling properties of pH‐sensitive hydrogels based on chitosan and poly(methacrylic acid) semi‐interpenetrating polymer network

A novel semi‐interpenetrating polymer network (semi‐IPN) hydrogel composed of chitosan and poly(methacrylic acid) was synthesized using formaldehyde as a crosslinker. The amount of crosslinker was searched and optimized. The structure of the hydogel was investigated by Fourier transform infrared (FTIR) spectroscopy. The spectrum shows that a structure of polyelectrolyte complex exists in the hydrogel. The effects of pH, ionic strength, and inorganic salt on the swelling behaviors of the hydrogel were studied. The results indicate the hydrogel has excellent pH sensitivity in the range of pH 1.40 to 4.50, pH reversible response between pH 1.80 and 6.80, and ionic strength reversible response between ionic strength 0.2 and 2.0M. The results also show that the hydrogel has a bit higher swelling capacity in a mix solution of calcium chloride (CaCl₂) and hydrochloric acid (HCl) solution than in a mix solution of sodium chloride (NaCl) and HCl. These results were further confirmed through morphological change measured by scanning electron microscope (SEM). © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1720–1726, 2005     

Synthesis of poly(2-oxo-1,3-dioxolane-4-yl) methyl methacrylate by polymer reaction of carbon dioxide and miscibility of its blends with copolymers of methyl methacrylate and ethyl acrylate

Polymeric epoxides were converted to corresponding five-membered cyclic carbonates in an effective manner. Poly(glycidyl methacrylate) (PGMA) was converted to a poly(2-oxo-1,3-dioxolane-4-yl) methyl methacrylate (PDOMMA) by the polymer reaction with carbon dioxide using tetraoctylammonium chloride (TOAC) as a catalyst. The miscibility of blends of PGMA or PDOMMA with copolymers of MMA and ethyl acrylate (MMA-EA) of two different EA compositions (2 and 5 wt %) was investigated by differential scanning calorimetry (DSC). The films of PGMA or PDOMMA and MMA-EA (2 and 5 wt %) blends were cast from N,N-dimethylformamide solution. An optical clarity test and DSC analysis showed that PDOMMA blends were miscible over the entire composition range, but PGMA was immiscible with the MMA-EA copolymers. It was also found that the miscibility of PDOMMA with 2 wt % MMA-EA copolymer was better than that of DOMMA with 5 wt % MMA-EA copolymer. The different miscibility behaviors were investigated in terms of Fourier transform IR spectra and interaction parameters based on the binary interaction model. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2161–2169, 2001     

Thermal and crystallization behavior of hydrogen‐bonded miscible blend of poly(3‐hydroxybutyrate) and enzymatically polymerized polyphenol

Enzymatically prepared novel polyphenol poly(4,4′‐dihydroxydiphenyl ether) (PDHDPE) is blended to modify the properties of biodegradable polyester poly[(R)‐3‐hydroxybutyrate] (PHB). Because the differential scanning calorimetry data show a single composition‐dependent glass transition for each blend, PHB and PDHDPE are found to be miscible in the amorphous phase. The crystallization of PHB is depressed by PDHDPE because PDHDPE reduces the molecular mobility and the flexibility of molecular chains of PHB. The Fourier transform IR spectra clearly indicate that PHB and PDHDPE interact through strong intermolecular hydrogen bonds between the carbonyl groups of PHB and the hydroxyl groups of PDHDPE. However, when PHB is blended with DHDPE monomer, no obvious hydrogen bonds are observed because of the phase separation and strong self‐intermolecular hydrogen bonds between DHDPE molecules. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2439–2449, 2005     

Optimization of PVC– PAN‐based polymer electrolytes

The hybrid plasticized polymer electrolyte composed of the blend of poly(vinyl chloride) (PVC) and poly(acrylonitrile) (PAN) as host polymer, propylene carbonate as plasticizer, and LiClO₄ as a salt was studied. An attempt was made to optimize the polymer blend ratio. XRD, Fourier transform infrared, and DSC studies confirm the formation of polymer–salt complex and miscibility of the PVC and PAN. The electrical conductivity and temperature dependence of ionic conductivity of polymer films are also studied and reported here. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Fluorinated polymers as stone‐protective materials: an FTIR study on intermolecular interactions

Attempts have been performed to obtain spectroscopic evidence of intermolecular interactions between fluorinated polymers to be used as protective materials and various stones. In this paper we report an investigation by means of FTIR spectroscopy on poly(vinyl fluoride)(PVF) which contains acid hydrogens that can give rise to intermolecular interactions with calcium carbonate. Spectral changes have been found in the C? H and C? F stretching regions at 3000–2840 and 1200–950 cm^?1, respectively. These last are attributed to intermolecular interactions of the polymer with CO₃^2? and with conformational changes of the macromolecular chain. Scanning electron microscopy investigations were also performed on marble slabs coated with a PVF film in order to gain information about the morphology of the polymer film. Copyright © 2004 Society of Chemical Industry     

Mixtures of poly(vinyl chloride) and copolyesters based on ε‐caprolactone and L‐lactide: Miscibility,thermal stability,and weathering resistance

Properties of the blends of Poly(vinyl chloride) (PVC) and poly(ε‐caprolactone) (PCLO) and copolyesters based on ε‐caprolactone and L‐lactide (LLA) prepared by rolling were studied. Incorporating the LLA units into the structure of PCLO the content of the crystalline phase was controlled. Miscibility of the blends was assessed using DMA, and basic mechanical properties were correlated with the type and content of the polymer plasticizer. The PVC blends containing up to 20 wt parts polyesters were miscible. The presence of the LLA units in the copolyester influenced negatively the thermal stability. On the other hand even small content of copolyester in the blend enhanced the resistivity against aging. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Miscibility and intermolecular hydrogen‐bonding interactions in poly(3‐hydroxybutyrate‐co‐3‐hydroxyhexanoate)/poly(4‐vinyl phenol) binary blends

The miscibility and hydrogen bonding interaction in the poly(3‐hydroxybutyrate‐co‐3‐hydroxyhexanoate)/poly(4‐vinyl phenol) [P(3HB‐co‐3HH)/PVPh] binary blends were investigated by differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). The DSC results indicate that P(3HB‐co‐3HH) with 20 mol % 3HH unit content is fully miscible with PVPh, and FTIR studies reveal the existence of hydrogen bonding interaction between the carbonyl groups of P(3HB‐co‐3HH) and the hydroxyl groups of PVPh. The effect of blending of PVPh on the mechanical properties of P(3HB‐co‐3HH) were studied by tensile testing. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

A study on compatibility of polymer blends of polystyrene/poly(4‐vinylpyridine)

Blends of polystyrene/poly (4‐vinylpyridine) have been prepared by casting from a common solvent. The compatibility of the blends was studied by using dilute solution viscometry (DSV), differential scanning calorimetery (DSC), Fourier transformation‐infrared spectroscopy (FT‐IR), and scanning electron microscopy (SEM). The relative viscosity versus composition plots for the blends are not perfect linear. The corresponding intrinsic viscosity values show negative deviation from ideal behavior when plotted against composition. Also, the modified Krigbaum and Wall interaction parameter, Δb, shows small and negative values for all compositions except for the blend PS/P4VP (25 : 75). The results indicate that the polymers are incompatible but small interaction values predict physically miscible blends which eventually show phase separation, as is observed in the present studies. However, the blends as obtained show a single, composition‐dependent, glass transition temperature that fits the Fox equation well, indicating the presence of homogeneous phase. The constant, k obtained from Gordon‐Taylor equation suggests intermolecular attraction between these polymers. FT‐IR and SEM support the results of DSV and DSC. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Viscoelastic properties of blends of poly(methyl methacrylate) and poly(styrene‐co‐acrylonitrile) having various acrylonitrile contents

Dynamic viscoelastic properties of blends of poly(methyl methacrylate) (PMMA) and poly(styrene‐co‐acrylonitrile) (SAN) with various AN contents were measured to evaluate the influence of SAN composition, consequently χ parameter, upon the melt rheology. PMMA/SAN blends were miscible and exhibited a terminal flow region characterized by Newtonian flow, when the acrylonitrile (AN) content of SAN ranges from 10 to 27 wt %. Whereas, PMMA/SAN blends were immiscible and exhibited a long time relaxation, when the AN content in SAN is less than several wt % or greater than 30 wt %. Correspondingly, melt rheology of the blends was characterized by the plots of storage modulus G′ against loss modulus G″. Log G′ versus log G″ plots exhibited a straight line of slope 2 for the miscible blends, but did not show a straight line for the immiscible blends because of their long time relaxation mechanism. The plateau modulus, determined as the storage modulus G′ in the plateau zone at the frequency where tan δ is at maximum, varied linearly with the AN content of SAN irrespective of blend miscibility. This result indicates that the additivity rule holds well for the entanglement molecular weights in miscible PMMA/SAN blends. However, the entanglement molecular weights in immiscible blends should have “apparent” values, because the above method to determine the plateau modulus is not applicable for the immiscible blends. Effect of χ parameter on the plateau modulus of the miscible blends could not be found. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008