Crystallization in Polymer Melts: Metamorphism of Flow Induced Nuclei
(460-463) International Polymer Processing #4 (2011)
Janeschitz-Kriegl and Ratajski of Johannes Kepler University, Austria, used  white polarized light  to study nucleation occurring during short term shearing of supercooled melts of iPP.  Blue specks show up some time after cessation of flow on a red background.  The blue color indicates that these tiny nuclei are oriented in the direction of previous flow. With prolonged waiting these specks extend over a large volume. At their centers spherulites start growing.  (RDC 8/15/2011)

078[2011]  Correlations of mechanical properties and microstructural parameters in annealed drawn film of liquid crystalline polymer In situ reinforced PP
e-Polymers(8/15/2011) (81)
[Abstract]
Saengsuwan of Ubon Ratchathani University,  Thailand, annealed drawn composite thin film based on thermotropic liquid crystalline polymer (TLCP) and polypropylene (PP) at 130 oC at different times.  X-Ray diffraction results reveal that the smectic mesophase transforms progressively into the monoclinic phase as annealing time is increased. Consequently, the true crystallinity (Xc), crystal thickness (L) as well as relative level of molecular orientation of PP crystalline phase in the annealed TLCP/PP films are increased significantly.  Also, the TLCP fibrils have no influence on the microstructure of PP crystalline phase.  The apparent crystallinity (Xc,a) of PP phase evaluated by DSC also increase significantly with annealing time. As a result, the increase of these microstructural parameters coupled with the reinforcement of TLCP fibrils could be contributed directly to the remarkable enhancement of mechanical properties of the annealed TLCP/PP film in both machine (MD) and transverse (TD) directions.  (RDC 8/15/2011)