Thermoreversible gelation of poly(ethylene oxide) biodegradable polyester block copolymers. II

A thermosensitive hydrogel based on biodegradable amphiphilic poly(ethylene glycol)–polycaprolactone–poly(ethylene glycol) block copolymers

“…Figure 3 showed the effect of the PCL block on the gel-sol transition diagram while the macromolecular weight of the PEG blocks was fixed at 1500. As is shown in figure 3, with increase in macromolecular weight of the PCL blocks from 750 to 1500, the critical gel temperature of the PEG-PCL-PEG copolymers increased from 19 • C for E1 (50 g/100 ml) to 54 • C for E3 (50 g/100 ml), whereas the critical gel concentration decreased from 50 g/100 ml for E1 to 35 g/100 ml for E3, and the critical precipitation temperature decreased slightly, which should be attributed to the enhancement of the hydrophobicity in the copolymer macromolecular main chain [4].…”

Biodegradable Block Copolymer–Tannic Acid Glue

“… 35 A gel-to-sol transition is known to occur in aqueous solutions of OL and related amphiphilic block copolymers as a function of the polymer concentration and composition. 36 This is ascribed to an upper critical solution temperature, which causes a breakdown in the micellar packing network by increased chain mobility and reduced micellar volume. The temperature-dependent frequency sweep data of both OL-M and OL-M/TA were consistent with a gel-to-sol transition above 75 °C ( Figure S11 ).…”

“…With increasing temperature, the PEO chains are known to be relatively dehydrated and become less soluble in aqueous environments . A gel-to-sol transition is known to occur in aqueous solutions of OL and related amphiphilic block copolymers as a function of the polymer concentration and composition . This is ascribed to an upper critical solution temperature, which causes a breakdown in the micellar packing network by increased chain mobility and reduced micellar volume.…”

Picolyamine based pH/temperature sensitive hydrogels

“…The hydrophobic interpenetrating network became stronger, and micelles were generally formed with fewer associated chains. 11,22 Consequently, the number of connection bridges between micelles increased, which resulted in the sol to gel and gel to sol phase transitions occurring at lower and higher CGTs, respectively. Therefore, the sol-gel phase diagram of the copolymer solution could be controlled (move to right or left) by changing the PCL/PEG ratio.…”