The cyclization of neoprene was achieved with the aid of a cationic catalyst system based on diethyl-aluminum chloride (Et2AlCl) and an organic chloride, allyl chloride (CH2 = CHCH2Cl) or benzyl chloride (C6H5CH2Cl). The main parameters of the cyclization process were investigated. Elastomers with low intrinsic viscosity, ready solubility and some gelling were obtained. Xylene was a good solvent for the cyclization process, which took place in a very short time (≤5 min). The products were characterized with IR, 1H-NMR, differential scanning calorimetry, and gel permeation chromatography. The polycyclic structure was determined. The degree of cyclization and the incorporated solvent content were estimated with a 1H-NMR method.
- Cationic cyclization