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Present designs for photorefractive polymer materials require three principal components, a charge generator (CG); a charge transport agent (CTA) or photoconductor; and a nonlinear optical (NLO) chromophore (Figure 1). 1, 2 Photoconducting polymers, doped with NLO and CG materials, have shown remarkable photorefractive effects but often lack appropriate materials properties (such as stability against crystallization) and are not amenable to simple combinatorial methods for optimization. Designer polymers with multiple components built into one covalent network demonstrate superior materials properties, 3-7 but typically require extensive monomer synthesis for each structural change. 8 An alternative design strategy is to begin with a polymer and graft on the components (Figure 2). 9-12 Herein, this strategy creates bifunctional polymers and leads to photorefractive materials, with net gain, derived from simple siloxane polymers and platinum catalyzed hydrosilation chemistry. 13 The synthesis strategy pivots on the platinum-catalyzed hydrosilation of olefins with poly (hydromethyl) siloxane. This method has been previously used to prepare homopolymers with photoconducting properties (1). 14, 15 Extension of the method to permit the incorporation of multiple olefins in the same reaction pot immediately opens up the possibility to synthesize a library of polymeric materials and to optimize their properties by combinatorial methods. 16-19 Initially, even parallel synthesis can lead rapidly to a prototype. In addition to the nature of the various components, the relative proportions can also be controlled. Thus, polymers of the general form xCG …