Crystalline phase, morphology

CRYSTALLINE PHASE MORPHOLOGY IN POLYMER/ORGANOCLAY NANOCOMPOSITES... 

One other mode of PCP crystallisation kinetics within the frameworks of the thermodynamic approach [39] was considered in paper [40]. It has been shown by the indicated approach that crystallisation kinetics is defined to a considerable extent by the drawing ratio X of polymers. At a certain value of X (XJ a crystalline phase morphology change from lamellar to fibrillar occurs that defines the transition to linear growth of the one-dimensional volume of crystallites. In paper [39] theoretical dependences of the parameter (1 -x/K ) on the crystallisation duration were obtained, corresponding to the equation ... 

MARZANTOWICZ, M., DYGAS, J.R., KROK, F., NOWII SKI, J.L., TOMASZEWSKA, A., FLORJAI CZYK, z. and ZYGADLO-MONIKOWSKA, E., 2006b. Crystalline phases, morphology and conductivity of PEO LiTFSI electrolytes in the eutectic region. Journal of Power Sources, 159(1 Spec, iss.), 420-430. 

As mentioned earlier, if there is a large disparity in sttiicture at the film-substrate interface, such as a crystalline phase growing on an amorphous, glassy, substrate, the film may detach and grow a separate morphology. 

PET fibers in final form are semi-crystalline polymeric objects of an axial orientation of structural elements, characterized by the rotational symmetry of their location in relation to the geometrical axis of the fiber. The semi-crystalline character manifests itself in the occurrence of three qualitatively different polymeric phases crystalline phase, intermediate phase (the so-called mes-ophase), and amorphous phase. When considering the fine structure, attention should be paid to its three fundamental aspects morphological structure, in other words, super- or suprastructure microstructure and preferred orientation. 

This rule of thumb does not apply to all polymers. For certain polymers, such as poly (propylene), the relationship is complicated because the value of Tg itself is raised when some of the crystalline phase is present. This is because the morphology of poly(propylene) is such that the amorphous regions are relatively small and frequently interrupted by crystallites. In such a structure there are significant constraints on the freedom of rotation in an individual molecule which becomes effectively tied down in places by the crystalhtes. The reduction in total chain mobility as crystallisation develops has the effect of raising the of the amorphous regions. By contrast, in polymers that do not show this shift in T, the degree of freedom in the amorphous sections remains unaffected by the presence of crystallites, because they are more widely spaced. In these polymers the crystallites behave more like inert fillers in an otherwise unaffected matrix. 

It was the objective of this work to investigate the effect of variation in block architecture (number and the order of the blocks) on the crystallinity level, morphology, the stress-strain and hysteresis behavior of this series of polymers. In addition, the composition ratio of the two block types is expected to play a crucial role in determining the bulk material properties of the block copolymers. This is related to the fact that the mechanical properties of block copolymer are typically influenced more substantially by the behavior of the continuous phase, as will be demonstrated.(1,22)... 

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