RAFT-Polymers with Single and Multiple Trithiocarbonate Groups as Uniform Gold-Nanoparticle Coatings
RAFT-Polymers with Single and Multiple Trithiocarbonate Groups as Uniform Gold-Nanoparticle Coatings
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DOI：
10.1021/ma4008626
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发表时间：
2013-06-25
期刊：
影响因子：
5.5
通讯作者：
Vana, Philipp
中科院分区：
文献类型：
--
作者：
Ebeling, Bastian;Vana, Philipp
详细分析了具有金纳米晶体核和含有单个或多个三硫代碳酸酯（TTC）基团的N-异丙基丙烯酰胺聚合物壳的纳米杂化物的纳米结构。聚合物在 RAFT 聚合中合成，然后通过柠檬酸盐还原接枝到金纳米颗粒（类似于 14 nm）。通过 TEM 分析揭示了金核的自组装六方晶格。当使用具有单一 TTC 端基且摩尔质量不断增加的聚合物作为涂层剂时，颗粒间距离增加，从而可以找到参考曲线。当使用沿其主链含有多个TTC基团的聚合物进行表面改性时，金核之间的间距出乎意料地低并且保持恒定，与聚合物的链长度和三硫代碳酸酯基团的数量无关，这表明——由尺寸排阻色谱法的结果支持——这些大分子通过几个金-TTC连接点包裹在金纳米颗粒周围。对于这些新颖且有前途的纳米混合物，绝对没有观察到交联。
The nanostructures of nanohybrids with gold-nanocrystal cores and shells of N-isopropylacrylamide polymers containing single or multiple trithiocarbonate (TTC) groups were analyzed in detail. The polymers were synthesized in RAFT polymerizations and then grafted to gold nanoparticles (similar to 14 nm) from citrate reduction. Analysis via TEM revealed self-assembled hexagonal lattices of gold cores. The interparticle distances increased, when polymers with single TTC end groups and growing molar masses were employed as coating agents, allowing for a reference curve to be found. When using polymers containing multiple TTC groups along their backbone for the surface modification, the spacings between the gold cores were unexpectedly low and remained constant, independent of the polymers' chain lengths and the number of trithiocarbonate groups, which shows-backed up by results from size-exclusion chromatography-that these macromolecules are wrapped around the gold nanoparticles with several gold-TTC junctions. Absolutely no cross-linking was observed for these novel and promising nanohybrids.