Dynamic Properties of Poly(DL-lactide) and Polyvinyl Alcohol Monolayers at the Air/Water and Dichloromethane/Water Interfaces

Polycaprolactone multicore-matrix particle for the simultaneous encapsulation of hydrophilic and hydrophobic compounds produced by membrane emulsification and solvent diffusion processes

“…PVA is a surface-active polymer which forms a protective film at the water/oil droplet interface [41]. Thus, the adsorbed PVA polymer layer can slow down the diffusion of water between the external and inner aqueous phase through the organic phase when the solidification of the PCL matrix was carried out in low volume of water (V sd /V th =1).…”

Development of a Constant Surface Pressure Penetration Langmuir Balance Based on Axisymmetric Drop Shape Analysis

“…Traditionally, the information about energy barriers to adsorption/penetration was obtained from dynamic surface tension measurements γ (t) at constant area (conventional Langmuir troughs) or at constant volume (pendant drop). But since with these techniques the adsorption density (t) is not directly accessible, normally one of the following procedures (which will not be discussed here) is employed: (a) use of interfacial equations of state (which, in general, are not very precise), or (b) the Gibbs-Duheim equation is extended to nonequilibrium (28), or the use of nonthermodynamic quantities like the reduced or effective diffusivity including the energy barrier, combined with elasticity measurements (29). With the only supposition that constant π implies constant , our device provides with the dilatation rate a direct measure of the rate of incorporation of surfactant molecules, which, for a given concentration, is only a function of π and therefore is an adequate measure of the energy barrier.…”

Polymeric microparticles containing protein prepared using a controllable combination of diffusion and emulsification steps as part of the salting out procedure

“…The PI and encapsulation efficiency were acceptable for the formulation produced at a speed of 300 rpm. A lack of diffusion control gives rise to a bimodal distribution with particle sizes around 15 µm (Boury et al, 1995;Shakesheff et al, 1997).…”