Center for Materials Innovation and Department of Chemistry, Washington University, St Louis, Missouri 63130, United States.
Biomacromolecules. 2011 Apr 11;12(4):1214-23. doi: 10.1021/bm101506j. Epub 2011 Mar 7.
Rigid nanoscale polymer rods were prepared by grafting preformed amine-terminated poly(styrene) and poly(tert-butyl acrylate) onto oxidized cellulose microcrystals. Low polydispersity polymers, grown using atom transfer radical polymerization, were characterized and purified prior to cellulose attachment. Oxidation of the cellulose microcrystal led to the formation of carboxylic acids on the surface of the microcrystals. Covalent attachment of the polymers onto the cellulose microcrystals was achieved via a carbodiimide-mediated amidation reaction. The length and diameter of the polymer-cellulose composites increased upon surface modification. Typically, polymer-cellulose composites are synthesized by a grafting-from method because it can be difficult to obtain sufficient graft density using a grafting-to preparation. However, the composites reported here comprised 60-64% grafted polymer by mass. This degree of grafting-to allowed the composite to form stable suspensions in organic solvents.
刚性纳米级聚合物棒通过将预形成的胺封端的聚苯乙烯和聚（叔丁基丙烯酸酯）接枝到氧化纤维素微晶上来制备。使用原子转移自由基聚合生长的低多分散性聚合物在附着到纤维素之前进行了表征和纯化。纤维素微晶的氧化导致微晶表面上形成羧酸。聚合物通过碳二亚胺介导的酰胺化反应共价连接到纤维素微晶上。聚合物-纤维素复合材料的长度和直径在表面改性后增加。通常，通过接枝到方法合成聚合物-纤维素复合材料，因为使用接枝到制备方法很难获得足够的接枝密度。然而，这里报道的复合材料的质量包含 60-64%接枝聚合物。这种接枝到程度允许复合材料在有机溶剂中形成稳定的悬浮液。
