Abstract
The iron (III) carboxylates (propionate, prp; cyclohexanecarboxylate, chc; naphthenate, naph) combined with triethylaluminum (AlEt(3)) were found to be very effective for the polymerization of 1-hexyne. The best experimental conditions in order to obtain good conversion of the monomer to a linear poly(1-hexyne) of relatively high molecular weight were as follows: the molecular ratio [Al]/[Fe] = 2, 3, 3, respectively, for Fe(prp),-AlEt(3), Fe(chc)(3)-AlEt(3) and Fe(naph)(3)-AlEt(3); the ageing time between the organometallic compounds before the addition of monomer: 1 hr at 50 degrees C; the Fe(III) catalyst concentration: 1.15 mmol.l(-1); the polymerization time and temperature: 48 hr and 50 degrees C, respectively. The rate of propagation was first-older with respect to the monomer concentration.