Hydrosilated carboranylenesiloxanes

Recently, Kolel-Veetil and Keller have modified this system to produce elastomeric networked polymers. The ambient-condition hydrosilation reactions between monomeric vinyl- or ethynyl-terminated carboranylenesiloxane and three different monomeric branched siloxane cross-linkers in hexane yielding these systems were catalyzed by the Karstedt catalyst.134 The reactions involving the vinyl-carboranylenesiloxane were reported to produce a set of completely hydrosilated networked polymers (105) (Fig. 65). In the case of the ethynyl monomer, the reactions were carried out at two different ratios, yielding a partially (106) and a com-... 

Figure 65 The hydrosilated networked polymers 105, 106, and 107 obtained from Karstedt catalyst-catalyzed hydrosilations involving monomeric vinyl- or ethynyl-terminated carboranylenesiloxane and a branched siloxane cross-linker in hexane. The Si-bound methyl groups have been omitted for clarity. (Adapted from ref. 134.)...

In the interest of producing elastomeric network polymers, Kolel-Veetil et al. reported the modification of the preceding hydrosilation reaction system. They reported the Karstedt catalyst-catalyzed ambient-condition hydrosilation reactions of a monomeric vinyl 14 or ethynyl-containing 17 carboranylenesiloxane with three different monomeric branched siloxane crossUnkers in hexane (Figure 15.19) [36]. The reactions involving the vinylcarboranylenesiloxane were reported to... 

In the case of the transparent hydrosilated networks of carboranylenesiloxanes obtained by hydrosilation reactions, the possibility exists for the use of the netwoiks in coating and sensor applications. Additionally, with the partially hydrosilated network systems, the opportunity does exist for the reaction and sensing of molecules at the organic unsaturation sites that are uniformly dispersed in the hydrosilated membrane. 

In the case of all of the carboranylenesiloxane network polymers produced either by thermal polymerization or by hydrosilation means, the opportunity exists for their use as neutron absorption materials that may find applications in nuclear reactor shields. The presence of boron atoms in these polymeric materials that are known to be exceptional neutron absorbing species by the well known boron neutron capture (BNC) reaction enhances the importance of them in nuclear applications [70]. 

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