The chain configurational properties of novolak p‐cresol–formaldehyde resins

Rotational isomeric state chain configurational analysis has been applied to the p‐cresol–form‐aldehyde chain structure. Steric interference allows the chain to be considered by using a twofold potential energy barrier. The bond rotational angles and conformational energies were set empirically to fit existing experimental dipole moment data, and the conformational angles were ±45° with a 132 cal/mole energy barrrier separating the g±g± from the g±g± rotational states. The data predict the existence of a cyclic tetramer in support of other researchers' experimental work. The limiting dipole moment ratio and characteristic ratio were computed to be 5.87 and 21.23, respectively. Support for this structure will have to wait for experimental data from higher‐molecular‐weight materials.