caa a22 4500 463191978 CHVBK 20180406164911.0 cr unu---uuuuu 170326e20070801xx s 000 0 eng 10.1007/s10973-007-8215-4 doi (NATIONALLICENCE)springer-10.1007/s10973-007-8215-4 Investigation of the rigid amorphous fraction in Nylon-6 [Elektronische Daten] [H. Chen, Peggy Cebe] A three-phase model, comprising crystalline, mobile amorphous, and rigid amorphous fractions (χ c, χ MA, χ RA, respectively) has been applied in the study of semicrystalline Nylon-6. The samples studied were Nylon-6 alpha phase prepared by subsequent annealing of a parent sample slowly cooled from the melt. The treated samples were annealed at 110°C, then briefly heated to 136°C, then re-annealed at 110°C. Temperature-modulated differential scanning calorimetry (TMDSC) measurements allow the devitrification of the rigid amorphous fraction to be examined. We observe a lower endotherm, termed the ‘annealing' peak in the non-reversing heat flow after annealing at 110°C. By brief heating above this lower endotherm and immediately quenching in LN2-cooled glass beads, the glass transition temperature and χ RA decrease substantially, χ MA increases, and the annealing peak disappears. The annealing peak corresponds to the point at which partial de-vitrification of the rigid amorphous fraction (RAF) occurs. Re-annealing at 110°C causes the glass transition and χ RA to increase, and χ MA to decrease. None of these treatments affected the measured degree of crystallinity, but it cannot be excluded that crystal reorganization or recrystallization may also occur at the annealing peak, contributing to the de-vitrification of the rigid amorphous fraction. Using a combined approach of thermal analysis with wide and small angle X-ray scattering, we analyze the location of the rigid amorphous and mobile amorphous fractions within the context of the Heterogeneous and Homogeneous Stack Models. Results show the homogeneous stack model is the correct one for Nylon-6. The cooperativity length (ξA) increases with a decrease of rigid amorphous fraction, or, increase of the mobile amorphous fraction. Devitrification of some of the RAF leads to the broadening of the glass transition region and shift of T g. Springer Science+Business Media LLC, 2007 Nylon-6 nationallicence rigid amorphous fraction (RAF) nationallicence TMDSC nationallicence Chen H. Department of Physics and Astronomy, Tufts University, 02155, Medford, MA, USA aut Cebe Peggy Department of Physics and Astronomy, Tufts University, 02155, Medford, MA, USA aut Journal of Thermal Analysis and Calorimetry Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 89/2(2007-08-01), 417-425 1388-6150 89:2<417 2007 89 10973 https://doi.org/10.1007/s10973-007-8215-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10973-007-8215-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Chen H. Department of Physics and Astronomy, Tufts University, 02155, Medford, MA, USA aut NATIONALLICENCE 700 1- Cebe Peggy Department of Physics and Astronomy, Tufts University, 02155, Medford, MA, USA aut NATIONALLICENCE 773 0- Journal of Thermal Analysis and Calorimetry Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 89/2(2007-08-01), 417-425 1388-6150 89:2<417 2007 89 10973 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer