Modified spin casting procedure

Two routes were explored to fabricate organic superlattices a modified spin casting procedure and multilayer coextrusion. Spin casting was selected as a relatively quick, low tech way to select the most promising photoresponsive polymer. 

After determining that compound 1 had a large photoinduced index of refraction change in the solid state and that it had enough thermal stability for incorporation into extruded superlattices, a large 50 g batch of the compound was synthesized for eventual use in the coextrusion system. "We also demonstrated the incorporation of 1 into a superlattice fabricated via the modified spin casting procedure (Figure 8). 

Buck and Fuhrmann [410] modified the spin casting film procedure by dropping the solution of a diblock copolymer onto an already rotating substrate, precleaned with an air plasma at 100 W for 1 min. They used air plasma for selective etching of the PMMA microphase in the PS/PMMA film, at a power of 40 W in steps of 5 s, keeping the sample in vacuum for 15 min after each etch period. Blend morphology and clay dispersion has been successfully studied by AFM of samples polished and physically and chemically etched, the latter by immersion in... 

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