Synthesis and stability research of reproducible aqueous polyurethane micelles with low de-blocking temperature

ABSTRACT Aqueous polyurethane micelles from 2,4,6‐trichlorphenol blocking terminal‐isocynate pre‐polymer were prepared which could be de‐blocked at low temperature. The prepared aqueous blocked polyurethane micelles (BPUMs) were uniform and spherical micro‐particles. The particle size was decreased with increase of the DMPA content, while it was enlarged at first and then gradually decreased by increasing R‐value. The stability of the micelles was affected by the R value, blocked efficiency and DMPA content. HDI‐BPUMs were more stable than HDI‐BPUMs at the same condition. The stability was further researched by the zeta potential combining with technique and viscosity tracking method, and the initial zeta potential be used as the stability criterion. In addition, a stabilization mechanism of the micelles was proposed. TCP‐blocked TDI‐BPUMs could be initially de‐blocked at about 75°C and TCP‐blocked HDI‐BPUMs was de‐blocked at about 80°C. The de‐blocking temperature could be further reduced in the presence of catalyst, but it was scarcely affected by the change of R‐value and DMPA content. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41908