Tuesday, 11:00 am Room 1315 March 29, 2016 Chemistry Building

Professor James Forrest Department of Physics & Astronomy

University of Waterloo,

Host: Mark Ediger For  over  20  years  now,  there  has  been  significant  interest  on  the  properties  of  highly  confined  glass  formers.    In  particular,  measurements  of  the  glass  transition  temperature  (Tg)    and  related  dynamics  have  sometimes  shown  significant  differences  from  the  properties  of    bulk  materials.  In  this  talk  we  will  review  the  literature,  and  describe  a  simple  physical  picture  that  allows  one  to  describe  the  measurements  of  apparently  reduced  Tg  values  in  both  thin  films,  and  nano  spheres.  We  will  then  introduce  a  simple  free  volume  model  for  dynamics  in  glass  forming  materials  where  the  importance  of  dynamical  length  scale  is  explicitly  derived.  That  model  is  found  to  provide  an  excellent  description  of  bulk  and  confined  glass  formers..  

Refreshments will be available prior to the seminar at 10:45 a.m. outside room 1315

Graduate Students can meet with the speaker in Room 8305F at 1:00 pm

The glass transition of polymers in confined geometries