Computer-generated atomic models are employed to evaluate the effect of disruptor units containing an m-phenylene ring on the modulus of aromatic polyester chains. The incorporation of isophthaloyl units results in quasiplanar chains which affect the chain modulus in a complex way. At a given concentration of disruptor units the chain modulus is strongly influenced by chain regularity and length. Chains containing m-phenylenedioxy and m-oxybenzoyl units cannot be represented by quasiplanar models and this implies a stronger detrimental effect of such units on chain modulus. The intuitive notion, employed in the design of thermotropic polymers, that the fewer disruptor units the better, is clearly a misconception.
Посилання на статтю:
Thermotropic polyesters: effect of m-phenylene disruptors on chain modulus / D. J. Johnson, I. Karacan* and J. G. Tomkat // Polymer. – 1992. – Vol 33. – P. 983-989.