adsorption of alcohols on low energy polymer surfaces. by William John Murphy Download PDF EPUB FB2
The adsorption of a range of polyvinyl alcohols, containing 12% residual acetyl groups, by sodium, calcium, and cesium montmorillonites has been studied. The polymers were strongly adsorbed by the clays.
The amount of polymer adsorbed depended on the method of mixing the polymer solution and the clay. When maximum adsorption was attained the amount of polymer adsorbed was sufficient to form Cited by: Alcohols are a significant group of surfactants which have been employed extensively in industry to improve the interfacial effects.
Recently, the change in surface potential (ΔV) of two isomeric hexanols, methyl isobutyl carbinol (MIBC) and 1-hexanol, was investigated by using an ionizing Am electrode. It clearly showed the opposite effects between MIBC and 1-hexanol in the interfacial Cited by: Contact angle studies of some low energy polymer surfaces.
Murphy, M. Roberts and these lower values are attributed to the preferential adsorption of the alcohol molecules at both the polymer-liquid and the polymer-vapour interfaces.
books or book chapters) do not need to formally request permission to reproduce material Cited by: All of the alcohols adsorb at low temperature by forming alkoxy and hydroxyl species on the surface.
On fully oxidized CeO 2 (), recombination occurs between some of the alkoxys and hydroxyls, resulting in alcohol desorption near by: Polymer adsorption by nanoparticles improves the stability of these types of suspensions against aggregation.
In this work, the surface adsorption of polyethylene glycol (PEG) and polyvinyl alcohol (PVA) with different molecular weights onto the Zinc oxide (ZnO) nanoparticles is studied. The effects of solution pH value andCited by: The neutral polymer, polyvinyl alcohol, has been shown to be adsorbed by the hydrated oxides gibbsite and goethite.
A reduction in adsorption on gibbsite is observed when it is dried prior to the. Like low-pressure plasma treatment, irradiation of a polymer surface with low energy ions promotes its adhesion to metals. Due to the complexity of the plasma–polymer interaction there are still many unresolved questions regarding the contribution and the efficiency of the surface modification by different particles generated in the plasma.
A statistical‐mechanical treatment of a polymer molecule adsorbed on a solid surface is given. The surface coverage by adsorbed molecules is assumed to be sufficiently low that the interactions of the adsorbed polymer molecules with each other may be neglected.
The partition function is derived for a polymer molecule with sequences of repeating units adsorbed at an interface and with. To improve methane storage capacity of porous organic materials, this work demonstrates that a rigid ladder-type backbone is more entropically favorable for gas adsorption and leads to a high gas uptake per unit surface area.
A porous ladder polymer network was designed and synthesized as the model material via cross-coupling polymerization and subsequent ring-closing olefin metathesis.
PEO is recognized as a polymer exhibiting low protein adsorption and low cell adhesion due to its minimal interfacial free energy with water, hydrophilicity, high-surface mobility and steric stabilization effects, and unique solution properties and molecular conformation in water. For these materials, the water CAs were above ∼°/° (adv/rec) and BET C constants were in the range of ∼, indicating uniform low-energy surfaces of closely packed alkyl groups on.
This correlates with the regions of emulsion stability at both high and low polymer concentrations, such that the instabilities arise in the regions of low or zero surface charge.
The results presented and their interpretation represent a development in the understanding of polymer–surfactant adsorption at the oil–water interface.
about the surface species during adsorption and reaction lowest energy barrier was kJmol presence of a network of hydrogen-bonded -SO3H groups at low alcohol concentrations and. Kink sites on high Miller index surfaces are either left- or right-handed and can be thought of as chiral, when the step lengths on either side of the kink site are unequal.
A silver single crystal was oriented and cut to expose the Ag() surface on one side and the Ag(6̄4̄3̄) surface on the other side. A system is proposed for naming these surfaces as Ag()S and Ag()R, respectively.
Purchase Hydrophobic Surfaces - 1st Edition. Print Book & E-Book. ISBN It is important to mention that several studies have already been done on the separation of short-chain alcohols by adsorption, mostly on silica aerogels and their organic derivatives, zeolites [29,30], activated carbons and polymer resins [, ], as adsorption requires less energy compared to other separation technologies.
Studies on the separation of alcohols by polymeric/co-polymeric gels. Present book chapter deals with production and potential applications of nanocarbon and nanocarbon-polymer composite materials, with special attention on the energy and environmental related sector and their significant role in enhancing the efficacy for.
Adsorption is the adhesion of ions or molecules onto the surface of another phase. Adsorption may occur via physisorption and chemisorption. Ions and molecules can adsorb to many types of surfaces including polymer surfaces.
A polymer is a large molecule composed of repeating subunits bound together by covalent adsorption of ions and molecules to polymer surfaces plays a role.
The added surfactant may also adsorb onto the membrane surface, 41 and thus reduce the interfacial free ene42 and promote adhesion and, subsequently, chemical attachment of the polymer to. This book documents the proceedings of the Fourth International Symposium on Polymer Surface Modification: Relevance to Adhesion held under the auspices of MST Conferences, LLC in Orlando, FL, JunePolymers are used for a variety of purposes in a host of technological applications and even a cursory look at the literature will evince that currently there is.
Penn et al. studied the chemisorption kinetics of amino-functionalised polystyrene chains on epoxy-functionalised flat surfaces in the presence of good and poor solvents. Figure shows the comparative kinetic curves for amino mono-functional polystyrene chemisorption, as derived from their reported results.
The system characteristics correspond to a true surface-linked polymer brush (2R g. The adsorption of surface-active molecules at a solid/liquid interface provides a versatile tool for modification and structuring of polymer surfaces.
The effect of oxyethylene groups on the adsorption properties of fatty alcohol polyoxyethylene ether sodium sulfate with narrow ethylene oxide distribution (AE m S, m = 3, 5, 7, 9) was characterized by means of the equilibrium surface tension, the dynamic surface tension and the contact angle.
The results show that at a concentration lower than the critical micelle concentration (CMC) the. The adsorption of polymers affects the cost and oil recovery in oil reservoir exploitation and the flocculation effect in the treatment of oil sand tailings.
The adhesion and adsorption of a hydrophobically modified polyacrylamide (HMPAM), i.e., P(AM-NaAA-C 16 DMAAC), on silica and asphaltene were investigated using surface force measurements, thermodynamic analysis and quartz crystal.
Bioethanol is used widely as a solvent and is considered a potential liquid fuel. Ethanol can be produced from biomass by fermentation, which results in low concentrations of alcohol in water. Conventional distillation is normally used to separate ethanol from water, but it required high energy consumption.
Therefore, alternative approaches to this separation are being pursued. Adsorption and desorption behavior of ionic and nonionic surfactants on polymer surfaces†. The adsorption behavior of polyvinyl alcohol (PVA) on the CaCO3/solution interface under the influence of sodium oleate (SOl) interaction was investigated by the adsorbed amount, FTIR spectra, X-Ray diffraction and zeta potential.
Effects of solid to liquid ratio and temperature was also examined. Observed increase of the PVA adsorption in presence of the sodium oleate resulted from a polymer. The polyimides exhibit large adsorption capacities for organic vapors such as benzene ( wt%) and cyclohexane ( wt%) at K and P/P o = In addition, the low-surface-energy trifluoromethyls significantly decrease the water uptake in the fluorinated polyimide compared to.
The primary approach used is through chemical modification of the surface through polymer coatings (Figure 3). Such coating provide a ‘stealth’ effect,  which is attributed to the high level of hydration of the hydrophilic polymer backbones, steric repulsion, and reduction of the surface energy of the biomaterial [6,].
Moreover, very few hydrogen bonds are formed between the adsorbate and the PVA surface, since both the protein fragments and the polymer chains separately optimize these interactions. Additional molecular dynamics simulations in explicit solvent were also performed to study the hydration of the adsorbed fragments and to estimate the possible.
The polymer-mineral composites were synthesized using vinyl monomers styrene, methyl acrylate, and butyl acrylate with nano dispersed oxides Fe 2 O 3, Cr 2 O 3, V 2 O 5 and SiO 2 in the presence of benzoyl peroxide and other peroxide initiators. Benzoyl peroxide adsorption on Fe 2 O 3, Cr 2 O 3, and V 2 O 5 surfaces was studied.
The adsorption parameters were found: adsorption-desorption.The London dispersive surface free energy (γ S L) was calculated using the Schultz and Dorris–Gray method.
The maximum surface energy value of (P(VDC-co-AN)) is found to be mJm − 2 and mJm − 2 in both methods respectively.If surface energy is decreased to below 60 mN m-1 by adding more propanol to the water/propanol mixture used as substrate, molecules with long side chains (n = ) that readily break on a /0.