Jihoon Shin 교수

ABA triblock copolymers were prepared using the renewable monomers menthide and lactide, by sequential ring-opening polymerizations. Initially, hydroxy telechelic polymenthide was synthesized by the diethylene glycol-initiated and tin(II) ethylhexanoate-catalyzed polymerization of menthide. The resulting 100 kg mol−1 polymer was used as a macroinitiator for the tin(II) ethylhexanoate-catalyzed ring-opening polymerization of d,l-lactide. Two polylactide−polymenthide−polylactide triblock copolymer

Polyurethane microcapsules containing water-borne polyurethane (PU) paint as a core material for self-repairing protection coatings were successfully manufactured <italic>via</italic> interfacial polymerization of diol–diisocyanate prepolymer and 1,4-butanediol as a chain extender in an emulsion solution.

Renewable ABA triblock copolymers were prepared by sequential polymerization of the plant-based monomers menthide and α-methylene-γ-butyrolactone (MBL or tulipalin A). Ring-opening transesterification polymerization of menthide using diethylene glycol as an initiator gave α,ω-dihydroxy poly(menthide) (HO-PM-OH), which was converted to α,ω-dibromo end-functionalized poly(menthide) (Br-PM-Br) by esterification with excess 2-bromoisobutyryl bromide. The resulting 100 kg mol(-1) Br-PM-Br macroinitia

Cellulose nanocrystals were prepared<italic>via</italic>short-time pretreatment by electron-beam irradiation in the solid state and disintegration using high pressure homogenization.

The iridium-catalyzed functionalization of the C−H bond of commercial polystyrenes with three types of tacticities (syndiotactic, isotactic, atactic) using boron reagents is reported. The boronate ester group in the polystyrene was further converted to hydroxy and arene via oxidation and Suzuki−Miyaura cross-coupling, respectively. These functionalizations proceeded without affecting the tacticity or chain length of the starting polymer, and the functional group concentration was easily controll

Pluripotency transcription programs by core transcription factors (CTFs) might be reset during M/G1 transition to maintain the pluripotency of embryonic stem cells (ESCs). However, little is known about how CTFs are governed during cell cycle progression. Here, we demonstrate that the regulation of Oct4 by Aurora kinase b (Aurkb)/protein phosphatase 1 (PP1) during the cell cycle is important for resetting Oct4 to pluripotency and cell cycle genes in determining the identity of ESCs. Aurkb phosph

Soluble syndiotactic polystyrene-supported triphenylphosphine (sPS–TPP) was synthesized by reacting borylated syndiotactic polystyrene with (4-bromophenyl)diphenylphosphine. A palladium catalyst, supported on sPS–TPP, effectively catalyzed Suzuki–Miyaura coupling reactions of aryl halides under homogeneous conditions. The polymer-supported palladium complex was recovered quantitatively by adding an equal volume of poor solvent to the polymer, and coupling products could be easily isolated by eva

Polyurethane microcapsules containing the triazole derivative and the oleate derivative as core materials were successfully prepared via interfacial polymerization in an oil-in-water emulsion of the diol-diisocyanate prepolymer and 1,4-butanediol as a chain extender under agitation or ultrasound sonication. The diameters of the resultant capsules which possess the triazole derivative core agent are 25–276 μm and shell thickness is 1.9–18.0 μm at controlled agitation rates (1000–6000 rpm). Typica

Highly compatible PLA plasticizers were prepared using lactide, which demonstrated “double green” based on renewability and biodegradation, and “dual performances” including flexible and elastomeric behaviors.

Efficient mixing and energy delivery by ball-milling promoted the lactide polymer growth from macroinitiators without the use of a solvent.

Abstract Hydroxy‐functionalized isotactic poly(1‐butene) was synthesized using transition metal‐catalyzed regioselective CH borylation at the side chain of the commercial polyolefin and subsequent oxidation of the boronic ester functionality. Functionalization up to ∼ 19 mol % of the termini of the ethyl side chain occurred without significant side reactions that could alter the polymer chain length. Esterification of the hydroxy group in the polymer with 2‐bromoisobutyl bromide generated a sid

Abstract Postfunctionalization of high‐molecular‐weight syndiotactic polystyrene (sPS) was achieved via combination of electrophilic bromination at the para‐position of the polymer aromatic ring and subsequent Suzuki–Miyaura cross‐coupling reactions with functionalized phenylboronic acids. The concentration of brominated styrene repeating unit in sPS was conveniently controlled by changing the ratio of added bromine relative to the polymer repeating unit. Brominated sPS (8.5 mol %) was converted