Metal-containing block copolymer

In order to achieve improved nanofabrication performance, novel functional block copolymer systems are strongly desired. Many researchers have recognized this, and novel functional systems such as metal-containing block copolymer systems have significantly simplified and improved nanofabrication processes. The combination of top-down microscale patterns with the bottom-up nanopatterns are attractive for integrating functional nanostructures into multipurpose on-chip devices. However, in order to use these materials in real-time applications, further development is still needed. More ground-shaking discoveries are needed and are also fully expected. 

Figure 5.1 Schematic representation of different approaches in fabricating metal-containing block copolymers into self-assembled nanostructures.

Chapter 1, written by Pittmann and Carraher, two of the early pioneers of the metallopolymer field, surveys the developments in the area in the 1960s and 1970s when metallopolymers were almost unknown. Chapter 2, by Abd-El-Aziz and Shipman, surveys the recent progress in the synthetic metallopolymer field. Chapter 3, by Rider and Manners, covers the recently emerging field of block copolymers with transition metal atoms in the main chain of at least one of the blocks. Synthetic routes to metal-containing block copolymers and applications in the field of... 

Fig. 14.3 Electron micrographs of some metal-containing block copolymers produced by ROMP units of M M2 in the copolymer shown in brackets. For systems see Tables 14.1 and 14.2. (a) Pd, system 22 (113 50), lamellar, before reduction, bar = 250 A (b) same as (a) but after reduction to metal, bar ==250 A (c) Pd, system 22 (163 10), spherical, after reduction to the metal, bar = 500 A (d) Au, system 28 (25 wt% M2 block), cylindrical (hexagonal packing), before heating, bar= 1000 A (e) same as (d) but after heating to form metallic Au particles, bar = 500 A (f) Sn, system 18 (120 25), lamellar, bar =1000 A (g) Ag, system 28 (28 wt% M2 block), lamellar, before heating, bar= 1000 A (h) same as (g) but after heating to form metallic Ag particles, bar= 1000A (i) Zn, system 21 (250 80), lamellar, bar = 1000 A. (a), (b), (c) Chan 1992b (d), (e), (g), (h) Chan 1992a ...

Block copolymers exhibit outstanding potential for a variety of applications as a result of their self-assembly into supramolecular structures (see Chapter 1, Section 1.2.5). However, the exploration of metal-containing multiblock materials was only begun in the early 1990s. Block copolymers derived from the living anionic polymerization of vinylferrocene were already mentioned in Section 2.2.1.1. In this section, side-chain metal-containing block copolymers are surveyed. Examples of block copolymers with metals in the main chain will be discussed in Chapter 3 (Section 3.3.8) and Chapter 7 (Section 7.2.3). 

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... 

IV. METAL-CONTAINING BLOCK COPOLYMERS FORMATION OF SELF-ASSEMBLED, SUPRAMOLECULAR MATERIALS AND NANOSCOPIC CERAMIC PATTERNS... 

Ramanalhan, M. and Darling, S.B. (2009) Thickness-dependent hierarchical meso/ nano scale morphologies of a metal-containing block copolymer thin film induced by hybrid annealing and their pattern transfer abilities. Sq(t Matter, 5, 4665-4671. 

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