US Patent 7339013 Thermosensitive polymers and thermoreversible gels obtained from these polymers

Polymers which comprise polymer chains of terpolymer type which are constituted by poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) of PEO-PPO-PEO form, which are modified at their termini by groups which can essentially be other chains of PEO-PPO-PEO, acid segments, amine groups or PEOs, these chains being linked to the terpolymer chains via chemical bridges which are constituted by urethane bridges, urea bridges, allophanate bridges and biuret bridges, and which comprise more than 80% by weight of said PEO-PPO-PEO.