Nanocomposites of Phosphonic-Acid-Functionalized Polyethylenes with Inorganic Quantum Dots

作者：Ruenzi Thomas; Baier Moritz C; Negele Carla; Krumova Marina; Mecking Stefan^*

来源：Macromolecular Rapid Communications, 2015, 36(2): 165-173.

DOI：10.1002/marc.201400441

• composite materials
• functionalized polyethylenes
• insertion phosphonic
• phosphonates
• polymerization
• quantum dots

Insertion of diethyl vinyl phosphonates and free vinyl phosphonic acid, respectively, into [(P boolean AND O)Pd(Me)(dmso)] ((P boolean AND O) = kappa(2)-P, O-Ar2PC6H4SO2O with Ar = 2-MeOC6H4) (1-dmso) occurs in a 2,1-as well as 1,2-fashion, to form a four-and a five-membered chelate [(P boolean AND O)Pd{kappa(2)-C, O-CH(P(O)(OR)(2))CH2CH3}] and [(P boolean AND O)Pd{kappa(2) -C,O-CH2CH(P(O)(OR)(2))CH3}] (R = H, Et). No decomposition or other reactions of 1 by free phosphonic acid moieties occur. Copolymerization in a pressure reactor by 1-dmso yields linear random poly(ethylene-co-diethyl vinyl phosphonate) and poly(ethylene-co-vinyl phosphonic acid). In these copolymerizations, reversible coordination of the phosphonate moieties of free monomer as well as chelate formation by incorporated monomer retards chain growth as also evidenced by relative binding studies of diethyl phosphonate towards 1. Post-polymerization emulsification of poly(ethylene-co-vinyl phosphonic acid) together with CdSe/CdS quantum dots (QDs) yields submicron (ca. 50 nm from dynamic light scattering (DLS) and transmission electron microscopy (TEM)) polymer particles with the QDs embedded in the functionalized polyethylene in a nonaggregated fashion. This embedding benefits the fluorescence behavior in terms of continuous emission and lifetime as revealed by wide-field fluorescence measurements. These composite particle dispersions are employed as a. masterbatch" together with an aqueous high density polyethylene (HDPE) dispersion to generate thin films (by spin-coating) and bulk materials (from the melt), respectively, in which the inorganic nanoparticles remain highly disperse.

• 出版日期2015-1