Novel types of layer-by-layer (LbL) assembly films were successfully fabricated onto a solid substrate through the inclusion complex formation between partially 2,3- O-methylated amyloses (MAs) and polytetrahydrofuran (PTHF). The formation of the LbL assembly films was confirmed by quartz crystal microbalance (QCM) analysis, atomic force microscopy (AFM) observation, and X-ray diffraction (XRD) measurement. The film formation was significantly affected by the methylation degree of amylose. When MAs with 8 and 20% methylation were used as hosts, the formation of LbL assembly films with PTHF was clearly observed. On the other hand, MAs with more than 33% methylation barely formed LbL assembly films with PTHF.
Isopropyl-substituted tri(ethylene glycol) is used as a chiral side chain of N-substituted poly(p-benzamide) in order to increase the difference of stability between the right-and lefthanded helical structures of the polymer. The target polymer is synthesized by the chain-growth condensation polymerization of the corresponding monomer with an initiator using lithium 1,1,1,3,3,3-hexamethyldisilazide as a base. A circular dichroism (CD) study of the polymer reveals that the CD signal is due to an excess of a thermodynamically controlled right-handed helical structure of the polymer, and that the replacement of the methyl group with a bulkier isopropyl group at the side chain of poly(p-benzamide) increases the abundance of right-handed helical structure in chloroform.
Cyclic graft copolymers consisting of poly(p‐methylstyrene) backbone and polystyrene branches with relatively low molecular weight distribution are synthesized with grafting‐from approach by living anionic polymerization of styrene from lithiated cyclic poly(p‐methylstyrene)s as multifunctional anionic macroinitiators for vinyl polymerizations. Precursors of the macroinitiators are prepared by ring‐closing metathesis reaction of α,ω‐divinyl‐terminated telechelic polymers. Subsequently, selective lithiation of tolyl groups in the cyclic polymers is conducted by s‐BuLi in the presence of tetramethylethylenediamine in cyclohexane in order to prepare the macroinitiators. Addition of styrene monomer into the cyclic macroinitiators provides shift in SEC to higher molecular weight due to graft polymerization from the macroinitiators to form cyclic graft copolymers. The unique polymer architecture of the obtained cyclic graft copolymers is confirmed by unimolecular observation by using atomic force microscopy.
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