Romão Rute I S, Ferreira Quirina, Morgado Jorge, Martinho José M G, da Silva Amélia M P S Gonçalves
Centro de Química Estrutural, Instituto Superior Técnico, Av. Rovisco Pais, P-1049-001 Lisboa, Portugal.
J Nanosci Nanotechnol. 2011 Apr;11(4):3151-61. doi: 10.1166/jnn.2011.3726.
The microphase-separation of Langmuir-Blodgett (LB) monolayers of a rhodamine B (RhB) end-labeled double hydrophilic block copolymer (DHBC), RhB-Poly(N,N-dimethylacrylamide)-b-poly(N,N-diethylacryl-amide) (RhB-PDMA(207)b-PDEA177) and the 1:1 segmental mixture of PDEA and RhB-PDMA homopolymers was followed by AFM. The DHBC LB films revealed a loose distribution of nano-aggregates with variable geometries below the lower critical solution temperature (LCST) of PDEA (32 degrees C) and low surface pressure (3 mN m(-1)). By increasing either the temperature above the LCST of PDEA or the surface pressure beyond the immersion regime of PDMA in the subphase (7 mN m(-1)) a dense nanopatterning was obtained. The absence of a corresponding regular nanopatterning in LB films of mixed homopolymers with the same composition highlights the role of the covalent bonding between PDEA and PDMA on the self-segregation of the two blocks at the air-water interface.
通过原子力显微镜（AFM）跟踪了罗丹明B（RhB）末端标记的双亲水嵌段共聚物（DHBC）、RhB-聚（N，N-二甲基丙烯酰胺）-b-聚（N，N-二乙基丙烯酰胺）（RhB-PDMA(207)b-PDEA177）以及PDEA与RhB-PDMA均聚物的1:1链段混合物的朗缪尔-布洛杰特（LB）单分子层的微相分离。在低于PDEA的低临界溶液温度（LCST，32℃）且表面压力较低（3 mN m⁻¹）时，DHBC LB膜显示出具有可变几何形状的纳米聚集体的松散分布。通过将温度升高到PDEA的LCST以上或表面压力提高到超过PDMA在亚相中浸入范围（7 mN m⁻¹），可获得致密的纳米图案。具有相同组成的混合均聚物的LB膜中不存在相应的规则纳米图案，这突出了PDEA与PDMA之间的共价键在气-水界面处两个嵌段的自分离中的作用。
