Poly , germanium-containing

Similar to the synthesis of a germanium-containing poly(p-xylene) (PPX), the tin-containing block copolymer of unsubstituted PPX and a diorganotin bridged PPX were prepared134 (Scheme 29). 

Kobayashi prepared a novel germanium-containing polymer, poly(germanium enolate), by reaction of a divalent germanium compound, germylene, with a cyclic a, -unsaturated ketone in the presence of a catalytic amount of a lithium compound (Scheme 11.65) [91[. 

Ito, H., Masuda, T. and Higashimura, T. (1996) Synthesis and properties of germanium-containing poly(diphenylacetylenes), J. Polym. Sci., Part A. Polym. Chem. 34, 2925-2929. 

The polymetallosiloxanes above may in fact be considered as variants of a series of polymetalloxanes which are akin to the silicones but which contain, for example, tin, germanium and titanium instead of silicon. Of the poly-organostannoxanes, dibutyl tin oxide finds use as a stabiliser for PVC and as a silicone cross-linking agent. Polyorganogermanoxanes have also been prepared (Figure 29.13). 

A thermographic material with only one heat-sensitive component is prepared by reaction of an organometallic compound such as phenylmercury(II) nitrate with a thiourea derivative.230 The product is ball milled and coated in a binder such as poly(vinyl acetate). Other organometallic compounds disclosed are those of bismuth, tin, gallium and germanium combined with a variety of sulfur-containing compounds such as thioamides and xanthates. 

Scheme 3.3 Poly(ester)s derived from diphenols containing silicon (Si) or germanium (Ge) and terephtalic acid dichlorides, (from ref. [46]).

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