Synthesis and characterization of some Para-nonylphenol formaldehyde resins

Para-nonylphenol formaldehyde resins with molecular weights ranging within 490 and 1400 were synthesized in acidic catalysis. The resins were characterized by spectral methods (i.r. and 1H-NMR spectroscopy) and as rheological behavior. The i.r. spectra put in evidence the bands characteristic to —OH phenolic group, respective to —CH2 and —CH3 groups placed in the nonyl radical, and the bands for substituents in positions of the aromatic ring as follows: 1.2, 1.4 and 1.2.4, respectively. With the aid of 1H-NMR spectroscopy there have been calculated some structural parameters, such as: formaldehyde/para-nonylphenol molar ratio and the number of aromatic protons per phenolic units. The variation of the apparent shear viscosity vs the shear rate showed that para-nonylphenol formaldehyde resins have a non-Newtonian rhelogical behaviour of pseudoplastic type.