TACK BEHAVIORS OF P-T-OCTYLPHENOL FORMALDEHYDE RESIN WITH RUBBER USING A MOLECULAR SIMULATION

Tack behaviours of p-t-octylphenol formaldehyde resin with rubbers, su ch as cis-l,4-polyisoprene and cis-1,4-polybutadiene, were studied usi ng molecular mechanics and dynamics. The structures of p-t-octylphenol formaldehyde resin were found to be that hydroxyl groups cluster in t he centre of the molecule by intramolecular hydrogen bondings and the t-octyl groups are extended out. The tack of p-t-octylphenol formaldeh yde resin with rubber is formed by intermolecular non-bond interaction s between the t-octyl groups of the resin and rubber chains. The inter action energies between one p-t-octylphenol formaldehyde resin molecul e and two rubber molecules were calculated to investigate the effect o f the molecular size of the resin on the tack strength. The interactio n energies for the dimer and the trimer of p-t-octylphenol formaldehyd e resin are greater than - 20 kcal/mol while those for the tetramer-de camer are less than - 40 kcal/mol. (C) 1998 Elsevier Science Ltd. All rights reserved.