Dresden 2006 – wissenschaftliches Programm

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CPP: Chemische Physik und Polymerphysik

CPP 13: POSTER New Experimental Techniques

CPP 13.4: Poster

Dienstag, 28. März 2006, 17:00–19:00, P3

Ultra-fast scanning calorimetry of Poly(butylene terephtalate) — •Alexander Minakov^1,2 and Christoph Schick² — ¹Natural Science Research Center, A.M. Pokhorov General Physics Institute, Vavilov st. 38, 119991 Moscow, Russia — ²University of Rostock, Department of Physics, Universitätsplatz 3, D-18051 Rostock, Germany

Ultra-fast scanning calorimetry (including controlled ultra-fast cooling) was applied to study crystallization and melting-reorganization processes in 40 ng Poly(butylenes terephtalate) (PBT) sample at the scanning rates up to 100000 K/s. We have found that the cold crystallization cannot be completely prevented in such sample even at the rates ca. 1000 K/s. The totally amorphous PBT sample can be obtained only at the rates ca. 10000 K/s. The melting-reorganization process was observed as follows. The sample was molted up to 350K with the rate 1000 K/s and cooled down to crystallization temperature with the same rate. The crystallization at 100 C, 130 C and 150 C was performed (3 min was enough for complete crystallization). Then the sample was cooled down to 24 C with the rate 1000 K/s. Next the melting-recrystallization curves were measured at the heating rates in the range 1000 - 40000 K/s. In the first case, the reorganization cannot be totally prevented even at 20000 K/s. We have found that few milliseconds were enough for recrystallization during fast heating after melting. In the sample crystallized at 130 C the recrystallization was prevented completely at the rate 10000 K/s, and at 5000 K/s in the sample crystallized at 150 C. We have found that 1 ms was not enough for reorganization in this case.