Preparation of novel ultrafine particles having solar energy conversion and storage ability and their application for composites

超支化聚酰胺胺(PAMAM)在无溶剂干燥体系中通过两步反应实现：(1)甲基丙烯酸甲酯与表面氨基的Michael加成反应；(2)端基与乙二胺的酰胺化反应。采用对甲苯磺酸催化双(2-羟甲基)丙酸在含氨基白炭黑表面的自缩合反应，将超支化聚酯接枝到白炭黑和白炭黑表面，研究了超支化聚酰胺接枝白炭黑表面端氨基与3-苯基-2，5-降冰片二烯-2-羧酸(NBD-COOH)直接缩合固定降冰片二烯(NBD)基团在白炭黑和白炭黑表面的作用。研究发现，在N，N‘-二环己基碳二亚胺(DCC)的存在下，NBD在二氧化硅和炭黑上的固定化反应是成功的。随着超支化PAMAM接枝二氧化硅上氨基含量的增加，固定在二氧化硅表面的NBD部分增加，但用于固定NBD部分的氨基比例降低。在DCC存在下，超支化聚酯接枝二氧化硅和炭黑表面的端羟基与NBD-COOH直接缩合，实现了NBD在二氧化硅和炭黑表面的固定化。QD固定的二氧化硅和炭黑储存的热能通过加热以热能的形式释放出来。QD固定化二氧化硅的储能随着光照时间的延长而增加，并在光照2 h后趋于恒定，约为30J/g二氧化硅。

The grafting of hyperbranched poly(amidoamine) (PAMAM) from the silica and carbon black surface was achieved by repeating two steps in solvent-free dry-system: (1) Michael addition of methylacrylate to amino groups on the surface and (2) amidation of terminal groups with ethylenediamine. Hyperbranched polyester was also grafted onto silica and carbon black surface by self condensation of bis(2-hydroxymethyl)propionic acid using p-toluenesulfonic acid as catalyst in the presence of silica having amino groups.The immobilization of norbornadiene (NBD) moieties onto silica and carbon black surface by the direct condensation of the surface terminal amino groups of hyperbranched PAMAM-grafted silica with 3-phenyl-2, 5-norbornadiene-2-carboxylic acid (NBD-COOH) was examined. It was found that the immobilization of NBD moieties onto silica and carbon black successfully proceeded in the presence of N, N'-dicyclohexylcarbodiimide (DCC) as a condensing agent. The immobilized NBD moieties onto the silica increased with increasing amount of amino groups of hyperbranched PAMAM-grafted silica, but the percentage of amino groups used for the immobilization of NBD moieties was decreased.The immobilization of NBD moieties onto silica and carbon black surface was achieved by the direct condensation of the surface terminal hydroxyl groups of hyperbranched polyester-grafted silica and carbon black with NBD-COOH in the presence of DCC.The immobilized NBD moieties on silica and carbon black were readily isomerized to quadricyclane (QD) by photo-irradiation in n-hexane. Stored thermal energy by QD-immobilized silica and carbon black was released as thermal energy by heating. The stored thermal energy of QD-immobilized silica increased with progress of the photo-irradiation time and became constant, about 30 J/g-silica, after 2 h.