Oligomers are the low-molecular-weight members of polymeric compounds in the molecular weight range from a few hundred to several thousand. Because of their unique physical properties, clearly differing from those of conventional low-molecular-weight compounds and high polymers, oligomers are currently used in many practical fields. This review summarizes methods for oligomer synthesis, primarily by addition oligomerization, and ralated reactions.
The scope of this review encompasses (i) the principle and examples of the synthesis of “telechelic” oligomers with a functional group at both chain-ends by addition (radical, cationic, anionic, and group-transfer) oligomerizations ; and the preparation of telechelic oligomers with ethynyl terminals and linear phenol-formaldehyde oligomers; (ii) the synthesis of “macromers” (oligomers having a polymerizable end-group) by ionic and radical mechanisms and their polymerization reactivity ; and (iii) the synthesis of cyclic or cyclic unit-containing oligomers. Problems in these oligomer syntheses are also discussed briefly.