Coleman Association Model Research Articles

Competitive Hydrogen Bonding Interactions Influence the Secondary and Hierarchical Self-Assembled Structures of Polypeptide-Based Triblock Copolymers

A new biocompatible triblock copolymer, poly(e-caprolactone-b-ethylene oxide-b-γ-benzyl l-glutamate) (PCL-b-PEO-b-PBLG), has been prepared through sequential ring-opening polymerizations, with two degrees of polymerization for the PBLG block segment when using an amino-terminated PCL-b-PEO diblock copolymer as the macroinitiator. The hydrogen bonding strengths (interassociation equilibrium constants) followed the order of phenolic/PEO (KA = 264.8) > phenolic/PCL (KC = 116.8) > phenolic/PBLG (KD = 9.0), indicating that the phenolic OH groups preferred to interact with the C–O–C units of PEO block, then the C═O units of PCL block, and finally with the C═O units of PBLG block. The hydrogen bonding behavior of these four competing functional units could be predicted accurately using the Painter–Coleman association model. These competitive hydrogen bonding interactions induced various miscibility behaviors and self-assembled hierarchical structures, ranging from the hexagonally packed cylinder structure of α-h...

Using Hydrogen-Bonding Interactions To Control the Peptide Secondary Structures and Miscibility Behavior of Poly(l-glutamate)s with Phenolic Resin

We synthesized three low-molecular-weight poly(glutamate)s—poly(γ-methyl l-glutamate) (PMLG), poly(γ-ethyl l-glutamate) (PELG), and poly(γ-benzyl l-glutamate) (PBLG)—through living ring-opening polymerization of their α-amino acid-N-carboxyanhydride derivatives and then blended them with phenolic resin to control the secondary structures of these polypeptides. Each of the three binary blends exhibited a single glass transition temperature (differential scanning calorimetry) and a single-exponential decay of proton spin–lattice relaxation times in the rotating frame [T1ρH; solid state nuclear magnetic resonance (NMR) spectroscopy], characteristic of a miscible system. The strength of the interassociative interactions depended on the nature of the hydrogen bond acceptor groups, increasing in the order phenolic/PELG > phenolic/PMLG > phenolic/PBLG, as evidenced through analyses using Fourier transform infrared (FTIR) spectroscopy and the Painter–Coleman association model. The fractions of α-helical conformat...

Local Relaxation Behavior and Dynamic Fragility in Hydrogen Bonded Polymer Blends

The dynamics of intermolecularly hydrogen-bonded polymer blends of poly(p-(hexafluoro-2-hydroxyl-2-propyl)styrene) with poly(vinyl acetate), poly(ethylene[30]-co-vinyl acetate[70]) and poly(ethylene[55]-co-vinyl acetate[45]) are investigated by broadband dielectric relaxation spectroscopy and Fourier transform infrared spectroscopy. Each blend component exhibits a glassy state (β) relaxation, and these relaxations are affected by the formation of intermolecular associations. The glassy state behavior of the blends can be modeled using the Painter−Coleman association model. All blends exhibit a single Tg and a single dielectric segmental (α) relaxation, indicative of strong segmental-level coupling. The fragility of the glass-formers depends on the volume fraction of intermolecularly associated segments, and the association model predicts which compositions have the highest fragilities. A relaxation related to the breaking and reforming of hydrogen bonds is observed at temperatures above the α process, and its temperature dependence varies systematically with ethylene content.

Miscibility enhancement through hydrogen bonding interaction of biodegradable poly(3‐hydroxybutyrate) blending with poly(styrene‐co‐vinyl phenol) copolymer

AbstractDifferential scanning calorimetry, one‐ and two‐dimensional Fourier transform infrared (FTIR), and solid state nuclear magnetic resonance (NMR) spectroscopy have been used to investigate the miscibility of and specific interactions between poly(styrene‐co‐vinyl phenol) (PSOH) and poly(3‐hydroxybutyrate) (PHB) upon varying the vinyl phenol content of the PSOH copolymer. The FTIR and solid state NMR spectra revealed that the phenol units of PVPh interact with the carbonyl groups of PHB through intermolecular hydrogen bonding. A miscibility window exists when the vinyl phenol fraction in the copolymer is greater than 22 mol % in the PSOH/PHB blend system, as predicted using the Painter–Coleman association model. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Miscibility enhancement of supramolecular polymer blends through complementary multiple hydrogen bonding interactions

AbstractWe have investigated the miscibility behavior and specific interactions of supramolecular poly[vinylbenzylthymine‐co‐(butyl methacrylate)] (T‐PBMA) and poly[(2‐vinyl‐4,6‐diamino‐1,3,5‐triazine)‐co‐styrene] (VDAT‐PS) blends with respect to their vinylbenzylthymine (VBT) and 2‐vinyl‐4,6‐diamino‐1,3,5‐triazine (VDAT) contents. Fourier transform infrared spectroscopy revealed that multiple hydrogen bonding interactions occurred exclusively between the VDAT and VBT units, which were stronger than adenine and thymine interactions. A miscibility window occurred in the VDAT‐PS/T‐PBMA blend system when the VBT and VDAT fractions in the copolymers were greater than 7 mol%, as predicted using the Painter–Coleman association model. Copyright © 2010 Society of Chemical Industry

Thermal and FTIR analysis of the miscibility and phase behaviour of poly (isobutyl methacrylate-co-4-vinylpyridine)/poly (styrene-co-acrylic acid) systems

The miscibility and phase behaviour of poly (isobutyl methacrylate-co-4-vinylpyridine) containing 20 mol% of 4-vinylpyridine (IBM4VP20) and poly (styrene-co-acrylic acid) containing 27 or 32 mol% of acrylic acid (SAA27 or SAA32) mixtures were investigated by DSC, TGA and FTIR spectroscopy in the 25–180 °C temperature range. The results showed that sufficient specific carboxyl–pyridine hydrogen bonding interactions occurred between these copolymers and led to miscible blends as cast from THF and to inter-polymer complexes of significantly improved thermal stability when butan-2-one is the common solvent. The self-association effect on the inter-polymer interactions was evidenced by the decrease of complexation yields, observed when the carboxylic content is increased above 27 mol% as with SAA32. The trend of phase behaviour predicted by a thermodynamic analysis of the specific interactions of hydrogen bonding type that occurred between the two components of the SAA27/IBM4VP20 blends, neglecting the weak carboxyl–ester interactions and the functional group accessibility effect, carried out using the Painter–Coleman association model that considers the screening effects, is in a fair agreement with the experimental results. Moreover an LCST is predicted to occur at relatively high temperature.

DNA-like interactions enhance the miscibility of supramolecular polymer blends

We have investigated the miscibility behavior, specific interactions, and supramolecular structures of blends of the DNA-like copolymers poly(vinylbenzylthymine-co-butyl methacrylate) (T-PBMA) and poly(vinylbenzyladenine-co-styrene) (A-PS) with respect to their vinylbenzylthymine (VBT) and vinylbenzyladenine (VBA) contents. 1H nuclear magnetic resonance spectroscopy and one- and two-dimensional Fourier transform infrared spectroscopy revealed that hydrogen bonding occurred exclusively between the VBA and VBT units. In addition, size exclusion chromatography, dynamic light scattering, and viscosity analyses provided evidence for the formation of supramolecular network structures in these binary blend systems. A miscibility window existed in the A-PS/T-PBMA blend system when the VBT and VBA fractions in the copolymers were greater than 11mol%, as predicted using the Painter–Coleman association model.

Effect of copolymer compositions on the miscibility behavior and specific interactions of poly(styrene-co-vinyl phenol)/poly(vinyl phenyl ketone) blends

Differential scanning calorimetry and one- and two-dimensional Fourier transform infrared (FTIR) spectroscopies have been used to investigate the miscibility of and specific interactions between poly(styrene-co-vinyl phenol) (PSOH) and poly(vinyl phenyl ketone) (PVPK) upon varying the vinyl phenol content of the PSOH copolymer. The FTIR spectra revealed that the phenol units of PVPh interact strongly with the CO groups of PVPK through intermolecular hydrogen bonding, and more weakly with the aromatic rings of PVPK through intermolecular π–π interactions. A miscibility window exists when the vinyl phenol fraction in the copolymer is greater than 20mol% in the PSOH/PVPK blend system, as predicted using the Painter–Coleman association model.

Hydrogen-bonding in polymer blends

Hydrogen bonding in polymer blends is a topic of great interest to polymer scientists because such systems have many potential applications. Introducing functional groups to one component to make it capable of forming hydrogen bonds to another, thereby enhancing the miscibility of otherwise immiscible blends, is one of the major achievements during the past 20 years of polymer science. The Painter–Coleman association model generally describes these interactions accurately. This Review discusses in detail the effects of hydrogen bonding on the miscibility and thermal properties of polymer blend systems.

Theoretical analysis of predictive miscibility of carbohydrate polymers – Software calculations for inulin–amylopectin systems

In this paper, the quantitative understanding of predictive miscibility gained with dextrans (which was demonstrated in our earlier paper, [Icoz, D. Z., & Kokini, J. L. (2007c). Quantitative prediction of miscibility in dextran systems as model carbohydrate polymers using Painter–Coleman association model. Carbohydrate Polymers, doi:10.1016/j.carbpol.2007.03.012] was tested on predictive miscibility/immiscibility in inulin–amylopectin blends at limited moisture conditions. Painter–Coleman association model was used with its capability to account for hydrogen bonding interactions on predictive miscibility. Thermodynamics of mixing, including free energy of mixing and its 2nd derivative, enthalpy and entropy of mixing, and free energy of hydrogen bonding contribution were calculated. The approximate prediction rules set with dextran systems using Painter–Coleman association model (i.e., use of hydrogen bond formation of analogue compounds to approximate hydrogen bonding in carbohydrates; using the intra-molecular screening parameter of γ = 0.30; and selecting low M w polymer as the self-associating component) was shown to successfully predict miscibility/immiscibility in inulin–amylopectin systems as an example for real carbohydrate blends.

Quantitative prediction of molecular miscibility in dextran systems as model carbohydrate polymers

This paper demonstrates the application of an advanced thermodynamic model to quantitatively predict molecular miscibility in model carbohydrate mixtures. It adds onto our previous paper on application of original Flory–Huggins theory that did not enable successful prediction of miscibility in dextran systems. In the current paper, Painter–Coleman association model was examined with its capability to account for strong hydrogen-bonding interactions on miscibility. Thermodynamics of mixing (free energy of mixing and its 2nd derivative, enthalpy and entropy of mixing, free energy of hydrogen-bonding contribution) were calculated using Miscibility Guide and Phase Calculator Software. It was quantitatively demonstrated that hydrogen-bonding significantly contributed to predictive miscibility in carbohydrate blends. When hydrogen bond formation of pentanol (an analogue compound for which hydrogen-bonding was previously characterized by Painter–Coleman group) was approximated to the hydrogen bond formation in dextrans, miscibility was successfully predicted. The generated knowledge is a step forward for understanding the thermodynamic basis for miscibility/immiscibility in carbohydrate polymer blends.

Interpolymer‐specific interactions and miscibility in poly(styrene‐co‐acrylic acid)/poly(styrene‐co‐N,N‐dimethylacrylamide) blends

AbstractThe miscibility or complexation of poly(styrene‐co‐acrylic acid) containing 27 mol % of acrylic acid (SAA‐27) and poly(styrene‐co‐N,N‐dimethylacrylamide) containing 17 or 32 mol % of N,N‐dimethylacrylamide (SAD‐17, SAD‐32) or poly(N,N‐dimethylacrylamide) (PDMA) were investigated by different techniques. The differential scanning calorimetry (DSC) analysis showed that a single glass‐transition temperature was observed for all the mixtures prepared from tetrahydrofuran (THF) or butan‐2‐one. This is an evidence of their miscibility or complexation over the entire composition range. As the content of the basic constituent increases as within SAA‐27/SAD‐32 and SAA‐27/PDMA, higher number of specific interpolymer interactins occurred and led to the formation of interpolymer complexes in butan‐2‐one. The qualitative Fourier transform infrared (FTIR) spectroscopy study carried out for SAA‐27/SAD‐17 blends revealed that hydrogen bonding occurred between the hydroxyl groups of SAA‐27 and the carbonyl amide of SAD‐17. Quantitative analysis carried out in the 160–210°C temperature range for the SAA‐27 copolymer and its blends of different ratios using the Painter–Coleman association model led to the estimation of the equilibrium constants K2, KA and the enthalpies of hydrogen bond formation. These blends are miscible even at 180°C as confirmed from the negative values of the total free energy of mixing ΔGM over the entire blend composition. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1011–1024, 2007

Sequence distribution affect the phase behavior and hydrogen bonding strength in blends of poly(vinylphenol-co-methyl methacrylate) with poly(ethylene oxide)

Experimental results indicate that the PEO was miscible with PVPh-r-PMMA copolymers as shown by the existence of single composition-dependent glass transition temperature over the entire compositions. However, the PVPh-b-PMMA copolymer with PEO shows a like closed loop phase-separated region in this copolymer/homopolymer blend system. Furthermore, FTIR reveals that at least three competing equilibrium are present in these blends; self-association (hydroxyl–hydroxyl), interassociation (hydroxyl–carbonyl) of PVPh-co-PMMA, and hydroxyl–ether interassociation between PVPh and PEO. Based on the Painter–Coleman Association Model (PCAM), a value for inter-association, KC=300 is obtained in PVPh-b-PMMA/PEO blend system at room temperature. Although the relative ratio of interassociation equilibrium constant of PEO to PMMA is larger in PVPh-b-PMMA/PEO blend system, the PVPh-r-PMMA/PEO blend system has greater Δν and greater homogeneity at the molecular scale than the PVPh-b-PMMA/PEO blend system because of the ΔK effect.

Hydrogen bonding interactions and miscibility between phenolic resin and octa(acetoxystyryl) polyhedral oligomeric silsesquioxane (AS‐POSS) nanocomposites

AbstractWe have synthesized a polyhedral oligomeric silisesquioxane (POSS) derivative containing eight acetoxystyryl functional groups [octa(acetoxystyryl)octasilsesquioxane (AS‐POSS)] and then blended it with phenolic resin to form nanocomposites stabilized through hydrogen bonding interactions between the phenolic resin's hydroxyl group and the AS‐POSS derivative's carbonyl and siloxane groups. One‐ and two‐dimensional infrared spectroscopy analyses provided positive evidence for these types of hydrogen bonding interactions. In addition, we calculated the interassociation equilibrium constant, based on the Painter–Coleman association model (PCAM), between phenolic resin and POSS indirectly from the fraction of hydrogen‐bonded carbonyl groups; quantitative analyses indicate that the hydroxyl–siloxane interassociation from the PCAM is entirely consistent with the classical Coggesthall and Saier (C and S) methodology. From a thermal analysis, we observed that the miscibility between phenolic and AS‐POSS occurs at a relatively low AS‐POSS content, which characterizes this mixture as a polymer nanocomposite system. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 673–686, 2006

Miscibility, specific interactions, and self‐assembly behavior of phenolic/polyhedral oligomeric silsesquioxane hybrids

AbstractThe miscibility of a phenolic resin with polyhedral oligomeric silsesquioxane (POSS) hybrids and the specific interactions between them were investigated with Fourier transform infrared (FTIR) spectroscopy and wide‐angle X‐ray diffraction (WAXD). An analysis of the morphology and microstructure was performed with polarized optical microscopy and atomic force microscopy (AFM). The interassociation equilibrium constant between the phenolic resin and POSS (38.7) was lower than the self‐association equilibrium constant of pure phenolic (52.3) according to the Painter–Coleman association model. This result indicated that POSS was partially miscible with the phenolic resin. A polarized optical microscopy image of a phenolic/POSS hybrid material (20 wt % POSS) indicated that the crystals of POSS were arranged evenly in the phenolic matrix; the self‐assembled array of POSS crystals was also confirmed by AFM. This phenomenon was consistent with the FTIR spectroscopy and WAXD analyses. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 1127–1136, 2004

Effect of Hydrogen Bonding Strength on the Microstructure and Crystallization Behavior of Crystalline Polymer Blends

Combinations of differential scanning calorimetry, Fourier transform infrared spectroscopy, optical microscopy, and small-angle X-ray scattering were used to investigate the influence of hydrogen bonding strength on the crystallization kinetics and morphologies in poly(e-caprolactone) (PCL) blends with three different well-known hydrogen bond donating polymers, i.e., phenolic, poly(vinylphenol) (PVPh), and phenoxy. The strength of the intercomponent interactions in the blend system depends on the hydrogen bond donor group and occurs, based on the Painter−Coleman association model, in the order phenolic/PCL > PVPh/PCL > phenoxy/PCL. Significantly reduced overall crystallization kinetics and crystal growth rate in PCL crystalline phase were also in the order phenolic/PCL > PVPh/PCL > phenoxy/PCL, which is consistent with the relative strengths of their intermolecular hydrogen bonding. Our experimental findings show that the hydrogen bonding strength has a greater effect on the rate of crystallization than d...

Miscibility and hydrogen bonding in blends of poly(vinyl acetate) with phenolic resin

The miscibility of phenolic resin and poly(vinyl acetate) (PVAc) blends was investigated by differential scanning calorimeter (DSC), Fourier transform infrared spectroscopy (FT-IR) and solid state 13C nuclear magnetic resonance (NMR). This blend displays single glass transition temperature (Tg) over entire compositions indicating that this blend system is miscible in the amorphous phase due to the formation of hydrogen bonding between hydroxyl groups of phenolic resin and carbonyl groups of PVAc. Quantitative measurements on fraction of hydrogen-bonded carbonyl group using both 13C solid-state NMR and FT-IR analyses result in good agreement between these two spectroscopic techniques. According to the proton spin–lattice relaxation time in the rotating frame (T1ρH), the phenolic/PVAc blend is intimately mixed on a scale less than 2–3nm. Furthermore, the inter-association equilibrium constant and its related enthalpy of phenolic/PVAc blends were determined as a function of temperatures by infrared spectra based on the Painter–Coleman association model.

Phase Behavior and Hydrogen Bonding in Ternary Polymer Blends of Phenolic Resin/Poly(ethylene oxide)/Poly(ε-caprolactone)

The phase behavior and hydrogen bonding in ternary polymer blends of phenolic resin, poly(ethylene oxide) (PEO), and poly(e-caprolactone) (PCL) were investigated by using differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). Although all three binary blends are respective miscible, there exists a closed immiscibility loop in the phase diagram due to the so-called “Δχ” and “ΔK” effects in this hydrogen-bonded ternary polymer system. The interassociation equilibrium constant based on the Painter−Coleman association model between phenolic resin and PEO can be indirectly calculated from the fraction of hydrogen-bonded carbonyl groups. Quantitative analyses show that the hydroxyl−ether interassociation is more favorable than the hydroxyl−carbonyl interassociation at room temperature. The interaction energy density value of BPEO/PCL= −2.85 cal/cm3 was obtained by comparing the theoretically predicted phase diagram with experimental data.

Effects of Copolymer Composition and Free Volume Change on the Miscibility of Poly(styrene-co-vinylphenol) with Poly(ε-caprolactone)

A series of poly(styrene-co-vinylphenol) (PSOH) copolymers were prepared and characterized. The miscibility and hydrogen bonding between the partially hydroxylated polystyrene with poly(- caprolactone) (PCL) blend were investigated by differential scanning calorimetry and Fourier transform infrared spectroscopy. The copolymers containing higher than 13 mol % vinylphenol were found to be fully miscible with PCL according to differential scanning calorimetry studies. Quantitative analyses on the fraction of hydrogen-bonded carbonyl groups in the solid state were made by FTIR spectroscopy, and good correlations between thermal behaviors and infrared results were observed. The critical vinylphenol content of 0.1 mol % in PSOH copolymer for the blend to be miscible was predicted from the Painter- Coleman association model and binary interaction model. The discrepancy between the experimental result and theoretical prediction is probably caused by significant free volume increase in this blend system, which is analyzed by the Kovacs' free volume theory. The free volume of the PSOH/PCL is increased which give a positive contribution in the Gibbs free energy. As a result, the polystyrene needs to incorporate more poly(vinylphenol) in PSOH copolymer in order to overcome the free energy increased caused by the free volume increase predicted by the Painter-Coleman association model and the binary interaction model.

Effect of copolymer composition on the miscibility of poly(styrene- co-acetoxystyrene) with phenolic resin

The miscibility behavior and specific interaction of phenolic/polystyrene- co-acetoxystyrene, (PS- co-PAS) blends by varying acetoxystyrene contents of the PS- co-PAS copolymer were investigated by differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR). A miscibility window was found when the acetoxystyrene fraction in the copolymer is higher than 45 mol% in phenolic/PS- co-PAS=50/50 blend system. Painter–Coleman Association Model (PCAM) is able to predict the miscibility window at 150°C compared with our experimental results based on DSC analyses.