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Ketotifen controlled release from cellulose acetate propionate and cellulose ac...
Sobral, Manuela; Sobral, Abilio; Guthrie, J.; Gil, M.Abstract Ketotifen was immobilised in cellulose acetate propionate (CAP) membranes and in cellulose acetate butyrate (CAB) membranes. The characteristics of each system were evaluated under a range of experimental conditions. The topography and uniformity of the membranes was assessed using scanning electron microscopy. The release characteristics associated with Ketotifen were monitored spectrophotometrically...
Polymer blends: the PC-PBT case
Santos, J.; Guthrie, J.An example of commercially important binary polymer blends is that of PC–PBT composites. The current knowledge of the physical, mechanical and chemical properties of these blends is reviewed and updated in the light of interpretations based on Lewis acid–base intermolecular interactions, as quantified by inverse gas chromatography, carried out under infinite dilution conditions.
Characterisation of the surface of a cellulosic multi-purpose office paper by i...
Santos, J. M. R. C. A.; Gil, M. H.; Portugal, A.; Guthrie, J. T.The surface of multi-purpose cellulosic office paper has been analysed by inverse gas chromatography (IGC). The parameters determined were the dispersive component of the surface free energy, the enthalpy of adsorption and the entropy of adsorption of polar and apolar probes, the Lewis acidity constant, Ka, and the Lewis basicity constant, Kb. It can be concluded that the dispersive component of the surface fre...
The synthesis and characterization of new polymerizable pyrimidines: Immobiliza...
Pegiadou, S.; Guthrie, J. T.; Gill, M. H.Polymerizable quaternary allyl-pyrimidinium salts, that is, 1-allyl-4- amino-5-phenyl-pyrimidine (IV), 1-allyl-4-acetamido-5-phenyl-pyrimidine (V), 1-allyl-5-hydroxymethylamino-5-phenyl-pyrimidine (VI), and 1-allyl-pyrimidine (VIII) bromides, as well as 4-acrylamido-5-phenyl-pyrimidines II` and IV`, were synthesized and characterized. Three of the activated pyrimidine derivatives, the two acrylamido and one all...
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