Characterization of hydroxypropylmethyl- cellulose-stabilized emulsions

Kulicke, Werner‐Michael; Arendt, Oliver; Berger, M.

doi:10.1007/s003960050342

Cited by 8 publications

(8 citation statements)

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“…In the present study, we used the method given by Kulicke et al [37] as applied to a test gel that was constructed using hydroxyethylcellulose and Carbopol. The presence of the latter macromolecule is what gives rise to yield stress behavior in this gel [11].…”

Section: Resultsmentioning

confidence: 99%

The consequences of yield stress on deployment of a non-Newtonian anti-HIV microbicide gel

Park

Peters

Katz

et al. 2011

Journal of Non-Newtonian Fluid Mechanics

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A recent study in South Africa has confirmed, for the first time, that a vaginal gel formulation of the antiretroviral drug Tenofovir, when applied topically, significantly inhibits sexual HIV transmission to women [10]. However the gel for this drug, and anti-HIV microbicide gels in general, have not been designed using full understanding of how gel spreading and retention in the vagina govern successful drug delivery. Elastohydrodynamic lubrication theory can be applied to model such spreading of microbicide gels, which are inherently non-Newtonian [13,15]. A yield stress is emerging as one of the important properties of microbicide gel vehicle deployment, as this may improve retention within the vaginal canal. On the other hand, a yield stress may decrease the initial extent of the coating flow. Here, we first explain a certain yield stress paradox observed generally in many lubrication flows. Four conditions are determined, via scaling analysis, which mitigate the inconsistency in the use of lubrication theory to analyze the specific problem of elastic wall squeezing flow of yield stress fluid. Parameters characterizing these conditions are obtained experimentally for a test gel. Using them, it is shown that the lubrication approximation may be applied to the elastic wall-squeezing problem for this gel.

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Section: Resultsmentioning

confidence: 99%

The consequences of yield stress on deployment of a non-Newtonian anti-HIV microbicide gel

Park

Peters

Katz

et al. 2011

Journal of Non-Newtonian Fluid Mechanics

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“…During the graft polymerization, water dispersion of HPMC‐ g ‐PEA graft copolymer with spherical particles is formed. Each particle consists of the core of the hydrophobic PEA grafted chains and the hydrophilic shell of the HPMC backbone, and the stability of the water dispersion comes from the autologous emulsifying capacity of HPMC 35–41…”

Section: Resultsmentioning

confidence: 99%

γ‐Radiation‐Induced Graft Copolymerization of Ethyl Acrylate onto Hydroxypropyl Methylcellulose

Wang

2006

Macro Materials & Eng

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Summary: Graft copolymerization of EA onto water‐soluble HPMC was carried out using γ‐radiation using both simultaneous and preirradiation in an aqueous medium. The effects of radiation environment, radiation dose, monomer concentration, and reaction temperature on percentage of grafting (G) and grafting efficiency (GE) were investigated. For preirradiation, the observed values for G and GE were higher in air than in a nitrogen atmosphere. G and GE values are obviously higher for preirradiation; their maximum values were obtained for a radiation dose of 1.8 kGy. The grafting parameters increase for increasing monomer concentration up to 0.15 mol · L−1, where they reach their saturation values. In the case of preirradiation, the largest grafting parameters are obtained at 65 °C. The graft copolymers obtained were characterized by FTIR spectroscopy, TEM, SEM, and XRD methods. The method of irradiation significantly affects the mechanical properties of the grafted HPMC samples. Samples prepared by simultaneous irradiation show superior mechanical properties. In addition, the equilibrium humidity adsorption behaviors of the grafted copolymers were also studied, and the humidity resistance behavior of HPMC was enhanced through the grafting copolymerization.Transmission electron micrograph of the HPMC‐g‐PEA water dispersion.magnified imageTransmission electron micrograph of the HPMC‐g‐PEA water dispersion.

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“…Generally, for an aqueous dispersion, the relationship between the viscosity and the volume fraction is described by the Mooney equation 28,29 :…”

Section: Ipn Aqueous Dispersionsmentioning

confidence: 99%

Preparation and properties of waterborne interpenetrating polymer networks composed of polyurethaneurea and graft vinyl ester resin

2009

J of Applied Polymer Sci

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Various waterborne interpenetrating polymer networks (IPNs) composed of polyurethaneurea (PUU) and graft vinyl ester resin were prepared from polyester polyol, dimethylolpropionic acid, isophorone diisocyanate, ethylenediamine and a well-defined graft vinyl ester resin containing butanol side chains (BO-g-VER). These anionic IPN aqueous dispersions were stable at the ambient temperature for >1 yr, and also had the excellent stability at low and high temperatures. The experimental results showed that the introduction of BO-g-VER network has not only greatly affected the particle morphology, stability and rheological behavior of these aqueous dispersions, but also rendered the films with the augmented surface hydrophobicity as well as the excellent water-resistance performance and mechanical properties. A synergistic effect was observed at a certain BO-g-VER composition (20 wt %) to give significant reinforcement to the PUU, resulting from the compatibility and/or the interpenetration between the PUU network and the BO-g-VER network.

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Characterization of hydroxypropylmethyl- cellulose-stabilized emulsions

Cited by 8 publications

References 0 publications

The consequences of yield stress on deployment of a non-Newtonian anti-HIV microbicide gel

The consequences of yield stress on deployment of a non-Newtonian anti-HIV microbicide gel

γ‐Radiation‐Induced Graft Copolymerization of Ethyl Acrylate onto Hydroxypropyl Methylcellulose

Preparation and properties of waterborne interpenetrating polymer networks composed of polyurethaneurea and graft vinyl ester resin

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