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Seminars
Contact :
Hèléne Berthoumieux
Tel : +33 (0) 1 40 79 xx xx
Paddy Royall
Tel : +33 (0) 1 40 79 xx xx
Gulliver seminars take place on Mondays at 11:30 AM in the F304 room, and typically last one hour including questions. The seminars are in English, and the scientific topics are mainly those studied in the laboratory.
Gulliver Seminar : Peter Olmsted (Georgetown University)
How does the glass transition temperature in polymers depend on molecular weight ?
I present a study of the molecular weight dependence, M, of the glass transition Tg(M),
xperimentally and with simple modeling. We find three regimes for T_g(M), roughly corresponding to (1) short inflexible oligomers, (2) oligomers with 2-20 or so Kuhn steps, and (3) polymeric molecules. We identify quasi-universal behaviour across wide classes of polymers, and argue that dynamic facilitation that balances intramolecular and intermolecular cooperatively is necessary in order to describe all three regimes.The coupling of intramolecular degrees of freedom to intermolecular degrees of freedom distinguishes polymer glasses from simpler glass formers such as rigid molecules or colloidal suspensions.
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Seminars (2)
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Gulliver Seminar : Haim Diamant (Tel Aviv University)
Lundi 29 avril de 11h30 à 12h30 - C162
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Gulliver seminar : Matthew Turner
Lundi 13 mai de 11h30 à 12h30 - C162
The audience is often heterogeneous - because of the wide range of scientific topics covered in the lab - so planning a talk for a broader audience would be preferred. The seminar is in English, and speakers are thus invited to prepare their slides in English.
The seminar starts at 11:30 AM. The speaker is asked to arrive in the lab at least 15 minutes in advance to set up their computer. The talks last typically 45 minutes, and are followed by a discussion time.