Approaches using Ring-opening Metathesis Polymerization ROMP

1 Approaches using Ring-Opening Metathesis Polymerization (ROMP) 

ROMP provided the first examples of block copolymers with pendant metal-containing groups. As discussed earlier, ROMP of substituted norbomenes has been used to prepare block copolymers with ferrocene side groups (see Section 2.2.1.2). 

Phase-separated, metal-containing block copolymers formed by ROMP offer interesting possibilities for the controlled formation of semiconductor and metal nanoclusters, which are of intense interest as a result of their size-dependent electronic and optical properties, as well as their catalytic behavior. Zinc-containing block copolymers generated by ROMP have been shown to form ZnS nanoclusters within the phase-separated organozinc domains upon treatment with gaseous H2S [96], The cluster sizes generated were up to 30 A, and their small size led to quantum size effects. For example, a band gap of 5.7 eV was measured for the 

---

Figure 27.3 Representative crosslinkers used for star polymer synthesis by the nodulus approach. The letters refer to the polymerization method used A, anionic C, cationic R, radical ROMP, ring-opening metathesis polymerization.

---