| For being able to self-assemble into versatile nanostructures in different lengthscales, the block copolymers (BCPs) are a good candidates for advanced technologydevices such as electronic, optic, magnetic devices and biosensors. To preparehierarchical functional BCPs, additional segments such as liquid crystals (LC) wouldbe incorporated into this system. The liquid crystal block copolymer(LC BCPs) whichcontain microphase separation of the BCPs and the long-range order of liquid crystalpolymer have been attention by the researcher. Meanwhile, the LC BCPsself-assembled would form various phase structure which exhibited hierarchicalsupra-molecular structures with ordering on both the nanometer and subnanometerlength scales.In previous work, we designed and synthesized a novel combinedmain-chain/side-chain LC polymer (MCSCLCP) based on the principle of MJLCPs,which exhibited hierarchical supra-molecular structures with ordering on both thenanometer and subnanometer length scales, that was the large two-dimensional (2D)rectangular positional order scaffold was constructed by the packing of thick mainchains, and the “sublevel” ordered structure was associated with the packingdetermined by the side chains. This paper will be focused on the research of phasestructure and the microphase separation for the coil-MCSCLCPs block copolymer,which produced the MCSCLCP into it.1. we have designed and successfully synthesized two series of narrow dispersibleLCBCPs (PS-b-PBBHCS, PEO-b-PBBHCS) via ATRP. The LC ordered structure andmicrophase separation for LC BCPs have been carried out by DSC andX-rayscatteringexperiments. expected that a novelty, complex supramolecularstructure will be builded by introducing the MCSCLCP into the block copolymer. Forthe PS-b-PBBHCS system, we find the phase structure of the BCPs is similar to thatof homo-PBBHCS, and Reducing the volume fraction of PBBHCS block results inthe phase morphology changing from lamellar to rectangular cylindrica. It isintriguing to note that PS-b-PBBHCS exhibits a hierarchically ordered structure inthree different length scales. As a contrast, for the PEO-b-PBBHCS system, althoughthe LC segment displays the same phase structure compared to the homo-PBBHCS,we hardly observed the phenomenon of microphase separation. 2. Furthermore, we introduce the ions(LiClO4) into the liquid crystal block polymerPEO-b-PBBHCS, then further study the change of phase structure and phase behaviorfor LC BCPs when the ion was introduced, at the same time, observe the changes ofmicrophase separation morphology for LC BCPs with different ion concentration.According to the results of the DSC and X-ray diffraction, no new phase structure wasobserved with the introduding of ions into the BCPs, but the phase structure havebeen promoted stability, and at the same time the temperature range of the phasestructure has been broaded. In the meanwhile, the microphase separation of the BCPscan be clearly observed when the ion concentration reached a certain level, and themorphology of microphase separation can also change with different ionconcentration, where the transition from lamellar to hexagonal columnar structurecould be observed as well. |
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