Related Experiment Video
Updated: May 29, 2026

Synthesis of Soft Polysiloxane-urea Elastomers for Intraocular Lens Application
Published on: March 8, 2019
Ureido-derivatized polymers based on both poly(allylurea) and poly(L-citrulline) exhibit UCST-type phase transition
Naohiko Shimada1, Haruka Ino, Kenji Maie
1Institute for Materials Chemistry and Engineering, Kyushu University, Motooka 744-CE11, Nishi-ku, Fukuoka 819-0395, Japan.
Abstract:
There are few examples of polymers that exhibit upper critical solution temperature (UCST) behavior under physiological conditions of temperature, pH, and ionic strength. In this study, we demonstrated that polymers with ureido groups undergo UCST-type phase transitions under physiologically relevant conditions. Poly(allylurea) copolymers showed UCST behavior at pH 7.5 in 150 mM NaCl even at the low polymer concentration of 0.13 mg/mL. Their phase separation temperatures (T(p)) could be controlled up to 65 °C. Similar thermosensitivity was observed with copolypeptides consisting of L-citrulline having an ureido group. This is the first demonstration of a non-vinyl polymer that shows UCST behavior under physiologically relevant conditions. We suggest that the ureido modification will be useful for production of polymer materials with UCST behavior in aqueous media.
More Related Videos
Related Concept Videos
Urea Cycle
Step-Growth Polymerization: Overview
Many natural and synthetic polymers are produced by...
Ion Exchange
Polymer Classification: Crystallinity
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
Polymer Classification: Stereospecificity
Phase II Reactions: Glucuronidation

