Hancox E, Derry M J, Greenall M J, Huband S, Al-Shok L, Town J S, Topham P D, Haddleton D M
Department of Chemistry, University of Warwick Coventry CV4 7AL UK
Aston Institute of Materials Research, Aston University Birmingham B4 7ET UK
Chem Sci. 2022 Mar 14;13(14):4019-4028. doi: 10.1039/d2sc00720g. eCollection 2022 Apr 6.
Three fluorinated, hydrophobic initiators have been utilised for the synthesis of low molecular mass fluoro-poly(acrylic acid) heterotelechelic homopolymers to mimic high chi ()-low diblock copolymers with ultrafine domains of sub-2 nm length scale. Polymers were obtained by a simple photoinduced copper(ii)-mediated reversible-deactivation radical polymerisation (Cu-RDRP) affording low molecular mass (<3 kDa) and low dispersity ( = 1.04-1.21) homopolymers. Heating/cooling ramps were performed on bulk samples ( 250 μm thick) to obtain thermodynamically stable nanomorpologies of lamellar (LAM) or hexagonally packed cylinders (HEX), as deduced by small-angle X-ray scattering (SAXS). Construction of the experimental phase diagram alongside a detailed theoretical model demonstrated typical rod-coil block copolymer phase behaviour for these fluoro-poly(acrylic acid) homopolymers, where the fluorinated initiator-derived segment acts as a rod and the poly(acrylic acid) as a coil. This work reveals that these telechelic homopolymers mimic high -ultralow diblock copolymers and enables reproducible targeting of nanomorphologies with incredibly small, tunable domain size.
三种含氟疏水性引发剂已被用于合成低分子量的氟代聚（丙烯酸）杂臂均聚物，以模拟具有亚2纳米长度尺度超细区域的高χ（）-超低二嵌段共聚物。通过简单的光诱导铜（II）介导的可逆失活自由基聚合（Cu-RDRP）获得聚合物，得到低分子量（<3 kDa）和低分散度（ = 1.04-1.21）的均聚物。对块状样品（250μm厚）进行加热/冷却升温，以获得由小角X射线散射（SAXS）推断出的热力学稳定的层状（LAM）或六方堆积圆柱状（HEX）纳米形态。结合详细的理论模型构建实验相图，证明了这些氟代聚（丙烯酸）均聚物具有典型的棒-线圈嵌段共聚物相行为，其中含氟引发剂衍生的链段作为棒，聚（丙烯酸）作为线圈。这项工作表明，这些杂臂均聚物模拟了高-超低二嵌段共聚物，并能够以令人难以置信的小且可调的域尺寸可重复地靶向纳米形态。
