Abstract
We describe the performance of a size-exclusion chromatographic system equipped with a differential viscometer (SEC-VISCO). The system has been applied to a wide variety of novolac resins for examining their true molecular weight in the range from 200 to 2,300,000. A Universal Calibration Curve (UCC) has been obtained for novolacs narrowly distributed in molecular weight. The curve is coincident with that obtained for standard polystyrenes, demonstrating that the SEC-VISCO measurement accompanied by UCC results in being possible to estimate the absolute molecular weights of novolac resins in the range higher than 200. Additionally, we have found that there is a small difference in the fluid hydrodynamic volume for three isomers of a novolac dimmer. The difference is mainly due to an intramolecular hydrogen bonding effect in the particular dimmer isomer.
