Codehydrocoupling (with various inorganic hydrides) followed by stannane-capping (with Ph2SnHCI) of 1,1-dihydrotetraphenylsilole (1) and 1,1-dihydrotetraphenylgermole (2) (9:1 mol ratio) produces electroluminescent stannane-terminated poly(silole-co-germole)s (3) in high yield. The polymerization yield and molecular weight with Selectride increase in the order L-Selectride < N-Selectride < K-Selectride. The molecular weights increase in the order L-Selectride < Red-Al < N-Selectride < K-Selectride < Super-Hydride.
View Article and Find Full Text PDFThe dry sol-gel co-polycondensation at toluene in ambient air atmosphere of p-X-C6H4SiH3 (X = H, CH3, CH3O, F, Cl) and p-H3Si-C6H4SiH3 (9:1 mole ratio) to co-silicas (p-X-C6H4SiO1.5)9(p-O1.5Si-C6H4SiO1.
View Article and Find Full Text PDFDehydropolymerization (with various inorganic hydrides) and subsequent germane/stannane-capping (with Me2GeHCI and Ph2SnHCI) of 1,1-dihydrotetraphenylsilole (1) give electroluminescent germane/stannane-capped polysiloles (2) in high yield. The polymerization yield and molecular weight with Selectride increase in the order L-Selectride < N-Selectride < K-Selectride. The molecular weights increase in the order Red-Al < K-Selectride < Super Hydride.
View Article and Find Full Text PDFWe demonstrate a new hierarchical self-assembly strategy for the formation of photonic arrays containing quantum dots (QDs), in which sequential self-assembly steps introduce organization on progressively longer length scales, ranging from the nanoscale to the microscale regimes. The first step in this approach is the self-assembly of diblock copolymers to form block ionomer reverse micelles (SA1); within each micelle core, a single CdS QD is synthesized to yield the hybrid building block BC-QD. Once SA1 is completed, the hydrophobic BD-QD building blocks are blended with amphiphilic block copolymer stabilizing chains in an organic solvent; water addition induces secondary self-assembly (SA2) to form quantum dot compound micelles (QDCMs).
View Article and Find Full Text PDFDropwise addition of water to blend solutions of block copolymer-stabilized quantum dots (QDs) and amphiphilic block copolymer stabilizing chains PS(665)-b-PAA(68) (PS = polystyrene, PAA = poly(acrylic acid)) in DMF induces self-assembly to form photoluminescent mesoscale QD/block copolymer colloids in water termed QD compound micelles (QDCMs). Here we demonstrate reproducible kinetic control of QDCM particle size and chain stretching within the external PAA stabilizing layer via changes in the initial polymer concentration and rate of water addition. By increasing the initial polymer concentration or decreasing the rate of water addition for a constant blend composition, larger QDCM particles are obtained.
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