Three triblock copoly(oxybutylene/oxyethylene)s, EssBIvEss, E71BzsE7a and E132B53E132, with similar composition (75-80 wt% E) but different chain lengths, were prepared by sequential anionic copolymerization, and their micellar and gelation properties in aqueous solution were determined. The methods used were light scattering intensity, photon correlation spectroscopy and gel permeation chromatography, together with observation of gelation. Measurements were made at 30°C over the full concentration range from dilute solution into the gel. The lower and upper temperature boundaries of the gel regions were identified. Phase separation was observed in dilute solutions of the copolymer of longest chain length (E132B53E132 ). Critical micelle and gel concentrations decreased markedly as chain length was increased, and micellar weights and sizes increased
Посилання на статтю:
Effect of chain length on the micellization and gelation of block copoly(oxyethylene/ oxybutylene / oxyethylene) E m B. Em / Christian V. Nicholas, Yun-Zhu Luo, Nan-Jie Deng, David Attwood*,John H. Collett, Colin Price and Colin Booth // Polymer. – 1993. – Vol 34. – P. 138-144.