Biomedical subjects

PDT Huibers

Publications and source records attributed to PDT Huibers.

3 recordsLinked to original sources

PubMed1998

The Effect of Polar Head Charge Delocalization on Micellar Aggregation Numbers of Decylpyridinium Salts, Revisited.

The distribution of charge in an isomeric series of decylpyridinium bromide surfactants is calculated using the AM1 semiempirical quantum mechanical molecular model. The aggregation numbers of the surfactants are shown to increase with a decrease in the residual partial charge in the alkyl tails, suggesting a change in the packing of the surfactants. The critical micelle concentration increases with a decrease in the partial charge of the head groups, indicating increased solubility of the surfactant molecule as charge is more widely distributed throughout the molecule. Copyright 1998 Academic Press.

Journal Article↗

PubMed1997

Predicting Surfactant Cloud Point from Molecular Structure

A general empirical relationship has been developed for estimating the cloud point of pure nonionic surfactants of the alkyl ethoxylate class. For a set of 62 structures, composed of linear alkyl, branched alkyl, cyclic alkyl, and alkylphenyl ethoxylates, cloud points can be estimated to an accuracy of ±6.3°C (3.7°C median error) using the logarithm of the number of ethylene oxide residues and three topological descriptors that account for hydrophobic domain variation. Copyright 1997Academic Press

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PubMed1997

Prediction of Critical Micelle Concentration Using a Quantitative Structure-Property Relationship Approach

Relationships between the molecular structure and the critical micelle concentration (cmc) of anionic surfactants were investigated using a quantitative structure-property relationship approach. Measured cmc values for 119 anionic structures, representing sodium alkyl sulfates and sodium sulfonates with a wide variety of hydrophobic and hydrophilic structures, were considered. The best multiple linear regression model involved three terms (descriptors) and had a correlation coefficient of R2 = 0.940. Very good correlations (R2 = 0.988) were obtained using three descriptors for a subset of 68 structures, with structural variation only in the hydrophobic domain. From the descriptors used in these regressions, one can conclude that the cmc is primarily dependent on the size (volume or surface area) of the hydrophobic domain and to a lesser extent on the structural complexity of the surfactant molecule.

Journal Article↗