Anne M. Mayes's research while affiliated with Massachusetts Institute of Technology and other places

Publications (172)

Patent
Full-text available
The present invention relates to synthetic methods for grafting hydrophilic chains onto polymers, particularly hydrophobic polymers such as poly(vinyl chloride) (PVC), poly(vinylidene fluoride) (PVDF), and chlorinated polypropylene (cPP). Resulting polymers include comb polymers which can have a microphase-separated structure of hydrophilic domains...
Article
Full-text available
The multilayer organization of sulfonated polyaniline/polyallylamine (SPAN/PAH) films was investigated by neutron reflectivity. Films were prepared by sequential adsorption of polycations and polyanions from dilute solution. Scattering contrast was achieved by selective deuteration of blocks of bilayers at varying intervals along the films. The int...
Article
We examined the resistance to bacterial adhesion of a novel polyacrylonitrile (PAN) ultrafiltration membrane incorporating the amphiphilic comb copolymer additive, polyacrylonitrile-graft-polyethylene oxide (PAN-g-PEO). The adhesion of bacteria (E. coli K12) and the reversibility of adhered bacteria were tested with the novel membrane, and the beha...
Article
Uncharged nanofiltration (NF) membranes can potentially perform size-based separations of small molecules. Thin film composite (TFC) membranes, prepared by coating a porous support membrane with a thin layer of poly(vinylidene fluoride)-graft-poly(oxyethylene) methacrylate (PVDF-g-POEM), were shown previously to have such capability, as well as exc...
Article
The oil industry produces large volumes of wastewater, including oil well produced water brought to the surface during oil drilling, and refinery wastewater. These streams are difficult to treat due to large concentrations of oil. Ultrafiltration (UF) is very promising for their treatment to remove oil, but has been limited by economic obstacles du...
Article
Membranes possessing both fouling resistance and permeate size cut-offs in the nanometer range would open membrane processes to numerous molecular separations in the biochemical, pharmaceutical and food industries. This study describes the preparation of novel thin film composite (TFC) nanofiltration (NF) membranes with the above properties, where...
Chapter
Polymer filtration membranes have been a focus of research since the late eighteenth century and became a thriving industry in the twentieth century. Today, membranes are used in commercial applications spanning from drinking water purification to gas separations, with a market that is expected to grow to more than $10 billion by 2010. This article...
Chapter
One of the most pervasive problems afflicting people throughout the world is inadequate access to clean water and sanitation. Problems with water are expected to grow worse in the coming decades, with water scarcity occurring globally, even in regions currently considered water-rich. Addressing these problems calls out for a tremendous amount of re...
Article
We report on spatial control of nanoporosity in polyelectrolyte multilayer (PEM) films using photopatterning and its effects on film optical and adsorption properties. Multilayers assembled from poly(acrylic acid-ran-vinylbenzyl acrylate) (PAArVBA), a photo-cross-linking polymer, and poly(allylamine hydrochloric acid) (PAH) were patterned using ult...
Article
Lithium methacrylate and heptadecane-functionalized poly(propylene oxide) (PPO) methacrylate based single-ion polymer electrolytes have been synthesized by radical copolymerization and neutralization. The thermal and electrical properties of the polymer electrolyte have been characterized by differential scanning calorimetry (DSC) and AC impedance...
Article
Full-text available
One of the most pervasive problems afflicting people throughout the world is inadequate access to clean water and sanitation. Problems with water are expected to grow worse in the coming decades, with water scarcity occurring globally, even in regions currently considered water-rich. Addressing these problems calls out for a tremendous amount of re...
Article
The present spot size for DNA microarrays is on the order of micrometers. However, there is a need for smaller arrays to allow the detection of smaller volumes of analytes. Although, SPM-based techniques are capable of fabricating nanoscale bio-arrays, such fabrication methods are serial in nature and consequently slow and expensive. A recently int...
Article
Full-text available
Films consisting of a vanadium pentoxide (i.e., V(2)O(5)) phase formed within a rubbery block copolymer were developed for their potential use as nanocomposite cathodes in lithium rechargeable batteries. Films were prepared by sol-gel synthesis from vanadyl triisopropoxide precursor in poly (oligooxyethylene methacrylate)-block-poly(butylmethacryla...
Article
The rapid development of molecular biology is creating a pressing need for arrays of biomolecules that are able to detect smaller and smaller volumes of analytes. This goal can be achieved by shrinking the average size and spacing of the arrays' constituent features. While bioarrays with dot size and spacing on the nanometer scale have been success...
Article
The effects of tether length on cell adhesion to poly(methyl methacrylate)-graft-poly(ethylene oxide), PMMA-g-PEO, comb copolymer films functionalized with the adhesion peptide RGD were investigated. Copolymers having PEO tether lengths of 10 and 22 EO segments were synthesized and coupled with a synthetic peptide that contained both RGD and the sy...
Article
Nanocomposite films were prepared by sol-gel synthesis from vanadium triisopropoxide with poly((oxyethylene)9 methacrylate)-graft-poly(dimethyl siloxane), POEM-g-PDMS, producing in situ growth of vanadium oxide within the continuous ion-conducting POEM domains of microphase-separated graft copolymer. The formation of vanadium oxide was confirmed by...
Article
Membrane fouling is one of the most important challenges faced in membrane ultrafiltration (UF) operations. In this study, polyacrylonitrile-graft-poly(ethylene oxide) (PAN-g-PEO), an amphiphilic comb copolymer with a water-insoluble polyacrylonitrile (PAN) backbone and hydrophilic poly(ethylene oxide) (PEO) side chains, was used as an additive in...
Article
The antifouling mechanism of a novel polyacrylonitrile (PAN) ultrafiltration (UF) membrane incorporating the amphiphilic comb copolymer additive, polyacrylonitrile-graft-polyethylene oxide (PAN-g-PEO), has been investigated using a laboratory-scale cross-flow test unit and atomic force microscopy (AFM). In fouling tests with a bovine serum albumin...
Article
Bone graft performance can be enhanced by addition of connective tissue progenitors (CTPs) from fresh bone marrow in a manner that concentrates the CTP cell population within the graft. Here, we used small peptide adhesion ligands presented against an otherwise adhesion-resistant synthetic polymer background in order to illuminate the molecular bas...
Article
Conductivity hysteresis and room temperature ionic conductivities >10−3 S/cm were recently reported for electrolytes prepared from blends of an amphiphilic comb copolymer, poly[2,5,8,11,14-pentaoxapentadecamethylene (5-hexadecyloxy-1,3-phenylene)] (polymer I), and a linear multiblock copolymer, poly(oligotetrahydrofuran-co-dodecamethylene) (polymer...
Article
This paper presents an overview of functional modifications of synthetic aliphatic polyesters and a new synthetic route to graft functional moieties onto the polyester backbone by a chemoselective approach. Aminooxy groups react efficiently and selectively with ketones or aldehydes to form oxime linkages under mild reaction conditions without catal...
Article
Ultrafiltration (UF) membranes, often employed in membrane bioreactors (MBRs), exhibit high susceptibility to fouling by extracellular polymeric substances (EPS). As potential alternatives, commercial polyvinylidene fluoride (PVDF) UF membranes were coated with the amphiphilic graft copolymer poly(vinylidene fluoride)-graft-poly(oxyethylene) methac...
Article
A range of proposed devices relies on the electronic, optical or magnetic properties of one-dimensional (1D) chains of nanoparticles. Here, well-controlled 1D arrays have been formed by templating a spherical-morphology block copolymer within a narrow groove. Significantly, the domains are distorted into ellipses with aspect ratio and major axis or...
Article
Comb copolymers comprising a poly(methyl methacrylate) (PMMA) backbone and short, polyethylene oxide (PEO) side chains, PMMA-g-PEO, have been proposed to self-organize at the polymer/water interface, resulting in the quasi-2D confinement of the backbone for chains at the immediate surface of PMMA-g-PEO films (D.J. Irvine et al., Biomacromolecules20...
Article
We report the synthesis of poly(acrylic acid-ran-vinylbenzyl acrylate) (PAArVBA), a photo-cross-linkable weak polyelectrolyte, and its incorporation into polyelectrolyte multilayer (PEM) films. PEM films assembled from PAArVBA and poly(allylamine hydrochloride) (PAH) are found to exhibit similar thickness trends with assembly pH as those previously...
Article
Full-text available
The relationship between microstructure and electrochemical performance was investigated in sputter-deposited V(2)O(5) thin-film cathodes. As-deposited and heat-treated films in unlithiated and lithiated states were studied by transmission electron microscopy, X-ray diffraction, and secondary ion mass spectroscopy. Film properties including orienta...
Article
Films consisting of a vanadium pentoxide (i.e., V 2 O 5) phase formed within a rubbery block copolymer were developed for their potential use as nanocomposite cathodes in lithium rechargeable batteries. Nanocomposite films were prepared by sol-gel synthesis from vanadyl triisopropoxide precursor in poly-(oligooxyethylene methacrylate)-block-poly(bu...
Article
Commercial hydroxy-terminated PEG-MA can be separated readily and completely from PEG dimethacrylate contaminant with chlorinated dimethylsilyl resin. Summary: Commercial hydroxy-terminated poly(ethylene glycol) monomethacrylates (PEG-MAs) contain poly(ethylene glycol) dimethacrylate, which leads to unfavorable gel formation on polymerization. Here...
Article
Amphiphilic graft copolymers having polysulfone (PSf) backbones and poly(ethylene glycol) (PEG) side chains were synthesized via reaction of an alkoxide formed from PEG and a base (sodium hydride) with chloromethylated polysulfone. The resulting polysulfone-graft-poly(ethylene glycol), PSf-g-PEG, materials were hydrophilic but water insoluble, rend...
Article
Full-text available
The single-ion conductor, BF3-incorporated poly[(oxyethylene)(9) methacrylate-ran-lithium methacrylate]- graft-poly(dimethyl siloxane), P(OEM-r-LiMA)-g-PDMS, was used as an electrolyte in cells containing a lithium anode and a thin-film vanadium oxide cathode. Cycle testing revealed an unanticipated high polarization which resulted in a significant...
Article
In this work, the fabrication of high energy density electrode materials for solid-state rechargeable batteries via block copolymer templating schemes was investigated. Atom transfer radical polymerization was used to synthesize the copolymer template poly((oligooxyethylene) methacrylate)-block-poly(butyl methacrylate), POEM-b-PBMA. Continuous, nan...
Article
Amphiphilic comb copolymers composed of a hydrophobic poly(methyl methacrylate) (PMMA) backbone and short, hydrophilic PEO side chains (PMMA-g-PEO) are known to self-organize at the polymer/water interface, resulting in the effective confinement of the backbone to two dimensions for chains at the surface of a PMMA-g-PEO film. Conformations of polym...
Article
A comparative study of silica-filled polystyrene and thin polystyrene films offers a new framework both for quantifying the typical shift in the glass-transition temperature of such systems, and prospects for the design of new nanocomposites.
Article
Core−shell polymer nanoparticles consisting of a low glass transition temperature (Tg) core of poly(n-butyl acrylate) or poly(2-ethylhexyl acrylate) and a glassy polystyrene shell were synthesized by two-stage emulsion polymerization. The obtained materials exhibit pressure-induced mixing of their components and could be processed at low temperatur...
Article
The use of thin film composite nanofiltration (NF) membrane incorporating a self-assembling graft copolymer with hydrophilic poly(vinylidene fluoride) (PVDF) backbone and hydrophilic poly(oxyethylene methacrylate) (POEM) side chain for size fractionation of metal nanoparticles was discussed. Phase separation of the backbone and side chains results...
Article
Lattice Boltzmann (LB) methods are employed to simulate the structural evolution of asymmetric membranes during the immersion precipitation fabrication process. A multi-phase, multi-component LB model is first developed, based on forcing interactions of the Flory–Huggins type. Boundary conditions specific to the process of immersion precipitation a...
Article
Solid-state polymer–silicate nanocomposite electrolytes based on an amorphous polymer poly[(oxyethylene)8 methacrylate], POEM, and lithium montmorillonite clay were fabricated and characterized to investigate the feasibility of their use as ‘salt-free’ electrolytes in lithium polymer batteries. X-ray scattering and transmission electron microscopy...
Article
Full-text available
Graft copolymer electrolytes (GCEs) of poly[(oxyethylene)(9) methacrylate]-g-poly(dimethyl siloxane) (POEM-g-PDMS) (70: 30) have been synthesized by simple free radical polymerization using a macromonomer route. Differential scanning calorimetry, transmission electron microscopy, and small angle neutron scattering confirmed the material to be micro...
Article
A microphase-separating single-ion conductor, poly[(oxyethylene)(9) methacrylate-ran-lithium methacrylate]-graft-poly(dimethyl siloxane), P(OEM-r-LiMA)-g-PDMS, was prepared by lithiating a precursor polymer synthesized by free radical methods using commercially available macromonomers. This material possessed a low conductivity, stemming from high...
Article
Full-text available
Single-ion conducting block copolymer electrolytes were prepared in which counter ions were tethered to the polymer backbone to achieve a lithium transference number of unity. Through tailored anionic synthesis, the influence of counter ion placement on conductivity was investigated. Incorporating the anions outside the ion-conducting [poly(ethylen...
Article
Thin film composite nanofiltration membranes have applications in many fields ranging from water purification to molecular separations. The microphase separation of amphiphilic graft copolymers consisting of a hydrophobic poly(vinylidene fluoride) (PVDF) backbone and poly (oxyethylene) methacrylate (POEM) side-chains, PVDF-g-POEM, was previously em...
Article
The process of chemoselective coupling applied to side chains of poly(ethylene oxide) (PEO) grafted to ketone-bearing polyetsers yielding biodegradable polyesters, was investigated. Chemoselective coupling was performed by mixing the ketone-bearing PCL and aminooxy-terminated PEO in chloroform at various stoichiometries and temperatures. Thermal st...
Article
Self-assembling materials are the building blocks for bottom-up nanofabrication processes, but many self-assembled nanostructures contain defects and lack sufficient long-range order for certain nanotechnology applications. Here we investigate the formation of defects in a self-assembled array of spherical block-copolymer microdomains, using topogr...
Article
The conformation of a cationic alpha-helical peptide (DDDDAAAARRRRR) adsorbed to anionic colloidal silica has been investigated by circular dichroism (CD) spectroscopy as a function of temperature and pH in order to examine how the structure of an adsorbed molecule responds to two simultaneous perturbations. Increased temperature destabilizes the h...
Article
Membranes that deliver nanoscale size selectivity are desirable for applications ranging from water treatment to molecular separations. Here we describe polymer thin film composite membranes coated with amphiphilic graft copolymers consisting of a poly(vinylidene fluoride) (PVDF) backbone and poly(oxyethylene methacrylate) (POEM) side chains, PVDF-...
Article
Polyelectrolyte multilayers constructed from poly(acrylic acid) and poly(allylamine hydrochloride) have been templated with shape specific dyes with absorbance maxima in the visible spectrum in order to test for binding specificity. Modification by crosslinking and immersion in solutions at elevated temperatures has favorably enhanced the binding p...
Article
Baroplastics are polymers capable of flow at reduced temperatures with the application of pressure. Block copolymers and core-shell nanoparticles comprised of a low glass transition (Tg) component, such as poly(butyl acrylate) and a high Tg component, such as polystyrene, component have been processed at temperatures as low as 25oC in simple compre...
Article
Graft copolymers of poly(vinylidene è uoride) with poly(methyl methacrylate) (PVDF- g-PMMA) and poly(oxyethylene methacrylate) (PVDF-g-POEM) were synthesized by the " grafting from" method, using polyvinylidene è uoride as macroinitiator for atom transfer radical polymeriza- tion (ATRP). The effects of polymerization temperature, reaction time and...
Article
The manufacturing of plastics traditionally involves melt processing at temperatures typically greater than 200 degrees C-to enable extrusion or moulding under pressure into desired forms-followed by solidification. This process consumes energy and can cause substantial degradation of polymers and additives (such as flame retardants and ultraviolet...
Article
Earlier experimental investigations performed on a family of block copolymers formed from styrene and a homologous series of n-alkyl methacrylates revealed a strong dependence of thermodynamic compatibility between the two blocks on the length of the alkyl side chain of the methacrylate. Here we report the effect of hydrostatic pressure on the phas...
Article
A compressible regular solution free energy model for multicomponent polymer blends is developed and used to obtain spinodal curves for three component systems, employing only pure component properties such as coefficients of thermal expansion, densities, and solubility parameters. The ability to predict, at least qualitatively, the phase behavior...
Article
We designed a molecular-scale separation system with a hydrophilic membrane surface containing a uniform channel size distribution. The essential concept is the introduction of an amphiphilic comb copolymer, whose microphase-separated structure of interconnnected domains serves as channels with controlled domain sizes for water molecules on a non-p...
Article
There has been great interest in recent years in the effect of pressure on the miscibility of polymer pairs; this effect is present in the displacement of the order/disorder temperature of block copolymers, which has been shown to be significant in some cases. In an attempt to exploit this effect, we have synthesized block copolymers that consist o...
Article
Full-text available
A self-organizing, nanocomposite electrode SONE system was developed as a model lithium alloy-based anode for rechargeable lithium batteries. In situ X-ray adsorption spectroscopy, galvanostatic testing, cyclic voltammetry, X-ray diffraction, and trans-mission electron microscopy were used to analyze the electrode, which was fabricated from a polye...
Article
A free energy model for the processing of polyelectrolyte multilayer (PEM) films via layer-by-layer assembly is developed for polyelectrolyte components of pH-tunable charge density, allowing for the prediction of cumulative thickness as a function of number of deposited layers, as well as the hydrated layer thickness and concentration of each adso...
Article
Self-organizing blends of poly(vinylidene fluoride) (PVDF) and an amphiphilic comb polymer having a PVDF backbone and poly(methacrylic acid) (PMAA), side chains are examined as a means to prepare membranes with pH-responsive separation characteristics. X-ray photoelectron spectroscopy analysis of membranes prepared from these blends indicates subst...
Article
To investigate the origin of noncircular pores in the selective layer of asymmetric poly(vinylidene fluoride) (PVDF), membranes cast by immersion precipitation, the mass transfer kinetics were controlled by casting membranes at different temperatures and casting solution concentrations. Interconnected surface pore morphologies were observed by scan...
Article
The use of self-setting calcium phosphate cements (CPCs) as bioresorbable bone-replacement implant materials presently is limited to non-load-bearing applications because of their low compressive strength relative to natural bone. The present study investigated the possibility of strengthening a commercially available CPC, alpha-BSM, by incorporati...
Article
The direct preparation of amphiphilic graft copolymers from commercial poly(vinylidene fluoride) (PVDF) using atom transfer radical polymerization (ATRP) is demonstrated. Here, direct initiation of the secondary fluorinated site of PVDF facilitates grafting of the hydrophilic comonomer. Amphiphilic comb copolymer derivatives of PVDF having poly(met...
Article
The full potential of wireless devices remains unattainable due to limitations in battery performance. It is the thesis of the guest editors and contributing authors of this issue of MRS Bulletin that there is much room for improvement, that we are still far from the practical limits of the technology, and that materials research has the capability...
Article
Immersion precipitated membranes with enhanced fouling resistance are prepared from blends of poly(vinylidene fluoride) (PVDF) and a free-radically synthesized amphiphilic comb polymer having a methacrylate backbone and poly(ethylene oxide) side chains. X-ray photoelectron spectroscopy analysis indicates substantial surface segregation of the comb...
Article
The objective of this work was to produce an ordered array of size-controlled gallium nitride (GaN) nanoparticles. The synthesis was performed by the in situ formulation and subsequent decomposition of cyclotrigallazane in a polystyrene (PS)-b-poly(4-vinylpyridine) (b-P4VP) block copolymer matrix. The matrix served as a templating medium to constra...
Article
Integrin-mediated cell adhesion is central to cell survival, differentiation and motility. Many cell responses induced by integrins require both receptor occupancy and receptor aggregation, and appear to be regulated by both biochemical and biophysical means. Multidomain extracellular matrix molecules may serve to foster integrin aggregation by pre...
Article
Full-text available
Block copolymer electrolytes of poly[(oxyethylene)(9) methacrylate]-b-poly(butyl methacrylate) (POEM-b-PBMA) (60:40 by mass) synthesized for the first time by atom transfer radical polymerization (ATRP) exhibited mechanical and electrical properties indistinguishable from those of materials made by the more difficult anionic polymerization method....
Article
The block copolymer electrolyte dynamics was discussed using solid-state nuclear magnetic resonance (NMR) line width and relaxation measurements. Parameters such as 1H rotating-frame relaxation times, 1H line widths of the poly(oligo-oxyethylene methacrylate) (POEM) block and 7Li linewidths were determined for several nonconductive blocks from the...
Article
In previous multilayer adsorption studies [1,2], thickness variations in polyelectrolyte layers with pH changes were plotted. In these studies where both the negatively- and positively-charged polyelectrolytes -- poly(acrylic acid) and poly(allyl amine), respectively -- were adsorbed at the same pH, the layer thickness showed sharp peaks in both la...
Article
Polymer miscibility has been the subject of many studies in the past; nevertheless, the phase behavior between polymer species is not totally understood and miscibility is restricted to a few known polymer pairs. Pressure is a thermodynamic parameter that can affect the phase behavior between polymer species and can be used to enhance the miscibili...
Article
Clustering of ligated integrins strongly influences integrin signaling and mechanical linkages between integrins and intracellular structures. Extracellular spatial organization of integrin ligands in clusters may facilitate clustering of bound integrins and thus potentially regulate cellular responses to a defined average amount of ligand in the e...
Article
A model polymer colloid with simple “recognition” ability was synthesized by dispersion polymerization using comb copolymer stabilizers that incorporate both 23-unit poly(ethylene oxide) and C18H37 side chains. Force interactions between beads of the resulting latex were examined using colloid-probe atomic force microscopy (CAFM) and Langmuir compr...
Article
A polymer electrolyte includes a self-doped microphase separated block copolymer including at least one ionically conductive block and at least one second block that is immiscible in the ionically conductive block, an anion immobilized on the polymer electrolyte and a cationic species. The ionically conductive block provides a continuous ionically...
Article
A simple and effective means of increasing the morphological detail in AFM phase micrographs of microphase separated block copolymer films is presented. Effective AFM phase imaging of microphase separated systems hinges upon the existence of appropriate contrast mechanisms such as differences in elasticity between the microphase separated domains....
Article
Directional solidification of cylinder forming block copolymer films confined between a directionally crystallizing solvent (benzoic acid) and a topographically patterned silicon substrate imparts a particular orientation to the block copolymer microdomains that is dependent of the solidification direction and the local film thickness. The substrat...
Article
Signaling through growth factor receptors controls such diverse cell functions as proliferation, migration, and differentiation. A critical question has been how the activation of these receptors is regulated. Most, if not all, of the known ligands for these receptors are soluble factors. However, as matrix components are highly tissue-specific and...
Article
Abstract A two-part review of research concerning block copolymer thin films is presented. The first section summarizes experimental and theoretical studies of the fundamental physics of these systems, concentrating upon the forces that govern film morphology. The role of film thickness and surface energetics on the morphology of compositionally sy...
Article
In an attempt to raise the transference number of Li ‡ to nearly unity in a solid polymer electrolyte, block copolymer materials have been prepared in which the counterions are tethered to the polymer backbone. This immobilizesthanion'' and, in effect, renders the material a single-ion conductor. For such so-called self-doped block copolymer electr...
Article
All solid state, thin-film batteries with the cell configuration of VOx/block copolymer electrolyte/Li have been designed, constructed, and tested. The additive-free (no carbon, no binder) cathode consisted of a dense film of vanadium oxide (∼200 nm thick), deposited on aluminum foil and prepared by laser assisted vapor deposition of vanadium metal...
Article
Full-text available
Microphase separated block copolymers consisting of an amorphous poly(ethylene oxide) (PEO)-based polymer covalently bound to a second polymer offer a highly attractive avenue to achieving both dimensional stability and high ionic conductivity in polymer electrolytes for solid-state rechargeable lithium batteries. However, due to the strong thermod...
Article
A simple model for the free energy of mixing of compressible polymer blends is derived, based on the regular solution model. Its ability to predict phase behavior for weakly interacting polymer pairs using only the pure component properties of mass density, solubility parameter, and thermal expansion coefficient is illustrated for mixtures of polys...
Article
We study the adsorption of polyelectrolytes onto oppositely charged surfaces as the surface charge density is varied while keeping the polyelectrolyte charge density fixed. As observed previously from multilayer adsorption studies,1,2 nonmonotonic adsorption behavior is obtained in the intermediate surface charge density regime, with anomalously th...
Article
Adhesion of cells for a variety of ligand-receptor pair have been studies previously and in general, the ratio of cells adhered at high and very low applied forces is used to determine the strength of adhesion. There is then an implicit assumption that the number of cells adhered decreases monotonically with increasing force. However, in recent exp...
Article
Modification of the Flory-Huggins regular solution model to account for thermal expansion effects through density-dependent diluted interactions yields a simple analytical expression for the free energy of mixing which can be employed to predict the miscibility of polymer blends based on pure component properties. The adequacy of our model at suppo...
Article
Tethering polymer chains to colloidal surfaces has long been a known route for modifying inter-colloidal forces. Through the regulation of the chemistry and physics of the chains, comb copolymers can provide a wide range of colloidal surface properties. Force-distance measurements by force microscopy and pressure-area measurements made on a Langmui...
Article
Component miscibility plays a critical role in the physical properties of polymer mixtures. Our inability to predict blend miscibility has limited the applications of polymer blends and their reuse by recycling.Here we present recent efforts towards tuning the miscibility of polymer mixtures based on a simple new model for the free energy of mixing...
Article
Theoretical and experimental studies were conducted to elucidate the structure and properties of amphiphilic comb polymer thin films presenting nanoscale clusters of Arg-Gly-Asp (RGD) peptides for control of cell adhesion on biomaterials. Combs comprised of a poly(methyl methacrylate) backbone and short poly(ethylene oxide) side chains were synthes...
Article
Given the intrinsic relation between phase behavior and performance in applications involving polymer mixtures, the thermodynamics of these systems has been the common focus of a wide body of experimental and theoretical studies. An elusive goal in this research field has been the ability to predict or simulate the degree of thermodynamic compatibi...
Article
Part 1 of these studies described poly(methyl methacrylate-r-polyoxyethylene methacrylate) P(MMA-r-POEM) comb polymers that present Arg-Gly-Asp (RGD) peptides at a surface in nanoscale clusters on a protein-resistant background for control of cell adhesion. Here in part 2, we examine surface segregation of these peptide-modified and unmodified comb...
Article
Full-text available
A two-part review of research concerning block copolymer thin films is presented. The first section summarizes experimental and theoretical studies of the fundamental physics of these systems, concentrating upon the forces that govern film morphology. The role of film thickness and surface energetics on the morphology of compositionally symmetric,...