A fluorescent polymer of 2-naphthol is prepared using the oxidative enzyme horseradish peroxidase encapsulated in the microstructured system of AOT/isooctane reversed micelles. The monomer, being amphiphilic, partitions to the oil−water interface with the hydroxyl moieties directed toward the microaqueous core. The enzyme is encapsulated in the water core. The precipitated polymer of naphthol has the morphology of single and interconnected microspheres and is soluble in a range of polar and nonpolar organic solvents. Poly(2-naphthol) shows a fluorescence characteristic of the naphthol chromophore and an additional well-resolved fluorescence attributed to an extended quinonoid structure attached to the polymer backbone. Further evidence of the quinonoid structure is obtained through UV, IR, and NMR spectroscopy. Characteristics of the synthesis and structure of poly(2-naphthol) are compared with those of a less fluorescent polymer, poly(4-ethylphenol).

Thiol-containing polyphenolics are enzymatically synthesized in the microstructured environment of reversed micelles. CdS semiconductor nanocrystallites, also synthesized in the water pools of reversed micelles, are then attached to these polymers through binding to the sulfhydryl groups. The polymer-CdS nanocomposite thus prepared exhibits luminescence characteristic of such quantum dot particles. Passivation of the CdS by the polymer suppresses low-energy emissions associated with surface recombinations, while slightly enhancing higher energy emissions resulting from the recombinations in the excitonic state of the crystallite interior. The polymer-CdS complex is stable in solution, and the solid form can be obtained in the morphology of microspheres.

Three different ceramic powders, viz. alumina, zirconia and silicon nitride were dispersed using two polyelectrolytes, one cationic (Betz 1190) and the other anionic (Darvan-C). All powders examined during the study could be well dispersed only under conditions of polymer dosage and pH such that the working pH is at least 2 pH units away from the primp of the powder-dispersant combination. The shift in the isoeleetrie point (IEP) of the powders were determined through electro-acoustic measurements on 1% volume suspensions. Specific free energy of interaction were also computed using a model based on the electrical double layer theory of surfactant absorption.

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