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Facile synthesis of hybrid block copolymers containing two segments that cannot be synthesized under the same polymerization mechanism still remains a great challenge in the field of polymer synthesis. Here we report on one-pot synthesis of hybrid block copolymers containing conjugated poly(phenyleneethylene) (PPE) and stereoregular poly-(phenyl isocyanide) (PPI) using palladium(II) complex as a single catalyst. Although the two blocks were polymerized via distinct polymerization mechanism, the block copolymerization were revealed to proceed in a living/controlled chaingrowth manner, afforded PPE-b-PPI block copolymers in high yields with controlled molecular weights, narrow molecular weight distributions, and tunable compositions. By using this synthetic method, amphiphilic PPE-b-PPI block copolymers containing hydrophobic PPE and hydrophilic PPI segments were facilely prepared. Such block copolymer can self-assembly into welldefined supramolecular structure in selective solvents. In addition, the one-pot block copolymerization method can be applied to the preparation of other hybrid block copolymers such as PPE-b-poly(1-isocyanohexadecane) (PPE-b-PIH) and PPE-bpoly(quinoxaline-2,3-diyl) (PPE-b-PQD) under living/controlled chain-growth manners.

Photoluminiscent (PL) cellulose aerogels of variable shape containing homogeneously dispersed and surface-immobilized alloyed (ZnS)x(CuInS2)1−x/ZnS (core/shell) quantum dots (QD) have been obtained by (1) dissolution of hardwood prehydrolysis kraft pulp in the ionic liquid 1-hexyl-3-methyl-1H-imidazolium chloride, (2) addition of a homogenous dispersion of quantum dots in the same solvent, (3) molding, (4) coagulation of cellulose using ethanol as antisolvent, and (5) scCO2 drying of the resulting composite aerogels. Both compatibilization with the cellulose solvent and covalent attachment of the quantum dots onto the cellulose surface was achieved through replacement of 1-mercaptododecyl ligands typically used in synthesis of (ZnS)x(CuInS2)1−x/ZnS (core–shell) QDs by 1-mercapto-3-(trimethoxysilyl)-propyl ligands. The obtained cellulose—quantum dot hybrid aerogels have apparent densities of 37.9–57.2 mg cm−3. Their BET surface areas range from 296 to 686 m2 g−1 comparable with non-luminiscent cellulose aerogels obtained via the NMMO, TBAF/DMSO or Ca(SCN)2 route. Depending mainly on the ratio of QD core constituents and to a minor extent on the cellulose/QD ratio, the emission wavelength of the novel aerogels can be controlled within a wide range of the visible light spectrum. Whereas higher QD contents lead to bathochromic PL shifts, hypsochromism is observed when increasing the amount of cellulose at constant QD content. Reinforcement of the cellulose aerogels and hence significantly reduced shrinkage during scCO2 drying is a beneficial side effect when using α-mercapto-ω-(trialkoxysilyl) alkyl ligands for QD capping and covalent QD immobilization onto the cellulose surface.

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