2024-03-29T06:03:02Zhttps://eprints.lib.hokudai.ac.jp/dspace-oai/requestoai:eprints.lib.hokudai.ac.jp:2115/861112022-11-17T02:08:08Zhdl_2115_20045hdl_2115_139Topology and Sequence-Dependent Micellization and Phase Separation of Pluronic L35, L64, 10R5, and 17R4 : Effects of Cyclization and the Chain EndsWatanabe, TomohisaWang, YuboOno, TomokoChimura, SatoruIsono, TakuyaTajima, KenjiSatoh, ToshifumiSato, Shin-ichiroIda, Daichi1000030525986Yamamoto, Takuyametadata only accessCreative Commons Attribution 4.0 Internationalcyclic polymerblock copolymerPluronicmicellizationcloud pointphase transitionThe topology effects of cyclization on thermal phase transition behaviors were investigated for a series of amphiphilic Pluronic copolymers of both hydrophilic-hydrophobic-hydrophilic and hydrophobic-hydrophilic-hydrophobic block sequences. The dye solubilization measurements revealed the lowered critical micelle temperatures (T-CMT) along with the decreased micellization enthalpy (Delta H-mic) and entropy (Delta S-mic) for the cyclized species. Furthermore, the transmittance and dynamic light scattering (DLS) measurements indicated a block sequence-dependent effect on the clouding phenomena, where a profound decrease in cloud point (T-c) was only found for the copolymers with a hydrophilic-hydrophobic-hydrophilic block sequence. Thus, the effect of cyclization on these critical temperatures was manifested differently depending on its block sequence. Finally, a comparison of the linear hydroxy-terminated, methoxy-terminated, and cyclized species indicated the effect of cyclization to be unique from a simple elimination of the terminal hydrophilic moieties.MDPI2022-05engjournal articleNAhttp://hdl.handle.net/2115/86111https://doi.org/10.3390/polym14091823Polymers1491823