Morphology of homogeneous copolymers of ethylene and 1-octene. III. Structural changes during heating as revealed by time-resolved SAXS and WAXD

Characterization of the dual crystal population in an isothermally crystallized homogeneous ethylene-1-octene copolymer

“…4). A similar paradox whereby a lower crystallinity is obtained after longer crystallization times was observed in the comparison between a slowly cooled and a rapidly quenched JW1120 sample [48]. In a given temperature window during heating the crystallinity of the quenched sample overtakes that of the slowly cooled specimen.…”

Molecular structure and driving force to metastable states: Janus faces in polymer crystallization

“…Some intriguing examples are the following: Phenomena like the existing pair of master curves found separately for crystallization during cooling and for melting on heating back of homogeneous copolymers could be tackled along this way Another topic is the fact that a quenched copolymer (into liquid nitrogen) can overtake a slowly cooled (at 0.1 °C min −1 ) copolymer with respect to the peak temperature and crystallinity during heating at 10 °C min −1 Why the melting and crystallinity curves are the same after cooling at very different rates in the case of homogeneous copolymers …”

Kinetics of phase separation and crystallization in poly(ethylene-ran-hexene) and poly(ethylene-ran-octene)

“…The long period increases with the isothermal crystallization time. For pure PEH and PEH/PEB blends samples [7,8], one could find such phenomena especially in crystallization condition just below T m : Some researchers found such long period increasing of ultra high density polyethylene [23], LLDPE [7,8] and pure PEOC [15] by lamellar thickening which is related to surface melting and re-crystallization processes of isothermal crystallization just below T m : Polymer meta-stable crystals have some defects especially during the early stage of crystallization. The meta-stable crystal could melt and recrystallize involving complete refolding of polymer chains to eliminate defects because the segments are having enough mobility at higher isotherm temperatures to carry out this rearrangement.…”