writer：Wei-wei Fan, Xiao-dong Fan,* Wei Tian,* Xuan Zhang, Gang Wang, Wan -bin Zhang, Yang Bai, and Xiu-zh
keywords：backbone-thermosensitivity, hyperbranched polyethers, dynamics of phase transition , self- assembled
source：期刊
specific source：Polym. Chem., 2014,5, 4022-4031
Issue time：2014年
In this study, a controllable thermo - induced phase transition process was  first  observed in the aqueous  solution  of  backbone -thermoresponsive  hyperbranched  polyethers.  According  to  the variable  temperature  UV?visible  spectrophotometry,  the  phase  transition  process  was extremely  slow  as  temperature  was  set around  lower  critical  solutio n  temperature  (LCST). Fluorescence tests showed that this slow phase transition behavior was related to the gradual thermally -induced  dehydration  of  hyperbranched  polyethers.  Based  on  this  unique  behavior, 
the  dynamics  of  phase  transition  was  conveniently  investigated  by  the  temperature - jump method.  Results  showed  that  the  dynamics  of  phase  transition  can  be  described  by  single exponential  functions,  and  the  dynamic  parameters  depended  on  temperature.  Dynamic  laser scattering  and  Transmission  electron  micro scopy  revealed  that  the  hyperbranched  polyether self- assembled  into  micelles  below  its  LCST,  while  the  temperature -dependent  aggregation 

occurred and complex micelles with larger size formed above LCST. Furthermore, the gradual aggregation process was in a ccordance with the rate- limited colloidal aggregation mechanism. Our research can contribute to the clarification of the  dynamics  and  mechanism  of this typical gradual  phase  transition  process  of  backbone - thermoresponsive  hyperbranched  polymers,  as well as their self - assembly and aggregation mechanism.

全文链接：http://pubs.rsc.org/En/content/articlelanding/2014/py/c4py00155a#!divAbstract