Formation of Acenaphthene-Formaldehyde Resin

Structure formation in urea-formaldehyde resin synthesis

The structure formation in acid promoted polycondensation and particularly in alkaline post-treatment with urea was studied by 13C NMR spectroscopy in the three-step synthesis of ureaformaldehyde resins. Trishydroxymethyl urea was identified as the constituent of the mixture of hydroxylmethylated urea derivatives obtained in alkaline conditions. The formation of methylenes linked to secondary o...

dimethylhydantoin-formaldehyde resin and polyvinylpyrrolidone

Berlin, A. and Smeets, J. (1974). European intercomparison programmes and harmonization oftechniqueswith special reference to heavy metals in biological fluids. Presented at the Fourth Annual Symposium onRecent Advances in the Analytical Chemistry of Pollutants, Basle, Switzerland. Bryce-Smith, D. (1972). Behavioural effects of lead and other heavy metal pollutants. Chemistry in Britain, 8, 240...

Resorcinol-Formaldehyde (R-F) Resin

Resorcinol-formaldehyde resin "Russian Red" endodontic therapy.

Resorcinol-formaldehyde resin is a material used in endodontic therapy in many foreign countries. With immigration to the United States increasing, American dentists need to become familiar with resorcinol-formaldehyde therapy. It contains two potentially toxic components, formaldehyde (liquid) and resorcinol (powder). Zinc oxide or barium sulfate may be used for radiopacity. When 10% sodium hy...

Thermal Degradation and Stability of Accelerated-curing Phenol-formaldehyde Resin

In order to study the thermal stability of accelerated-curing PF resin, the curing behavior of fresh PF resin was investigated in the presence of single accelerator of methylolurea derivatives (MMU), magnesium hydrate (Mg(OH)2), 25% aqueous solution of sodium carbonate (Na2CO3), and propylene carbonate (PC). Also their optimum combination was added in fresh PF resin. The thermal stability of cu...