Mesomorphic phases, morphology

Further work will be related to the development of curable systems as well as to a broader examination of the phase morphologies in the solid state. In addition, the dependence ofthe technologically relevant selectivity in gas permeation on the type and size of the resulting mesomorphous phases is currently under investigation. 

Pantani et al. [11] gave an extensive review on available models to predict and characterize the morphology of injection-molded parts. The authors themselves proposed a model to predict the morphology of injection-molded iPP, in which flow kinematics are computed using a lubrication approximation. Polymorphism was accounted for, using the Avrami-Evans-Nakamura equation to describe the crystallization kinetics of the mesomorphic phase, while the evolution of the a phase was modeled using Kolmogorov s model [122]. 

Over the past two decades, liquid crystal polymers (LCP s) have received a considerable amount of attention in both academic and industrial laboratories. Often termed mesomorphic (meaning having "middle form"), liquid crystalline phases have a degree of order between that of the zero ordered liquid and that of the three dimensional crystal lattice. Recent reviews of liquid crystal polymers have provided a fundamental understanding of the synthesis, classification, morphology, and rheology of this unique class of materials (52-541. 

The fact that certain structure-related phenomena tend to support one model, whereas others can be explained adequately only in terms of the other, underlines the limiting nature of either of the two concepts. The actual morphological structure of nylon is more complex and may involve paracrystals of any of the possible polymorphic forms, mesomorphic regions, and essentially amorphous domains. This is also indicated by a multiple melting phenomenon [279] that was investigated by high-temperature x-ray techniques and differential scanning calorimetry, and has been explained based on three phases — crystalline, intermediate, and liquid amorphous [280]. 

In the swollen block copolymeric materials, the insoluble block of the polymer aggregates into microphase separated domains that in turn are dispersed in well-defined, spatially periodic supramolecu-lar structures.(18) While the morphologies of these structures are sometimes indistinguishable from textures assumed by thermotropic (and lyotropic) MLCs, these block copolymer phases are frequently more solid-like in their physical properties. Multiple interconnections between microphase separated domains tend to establish static, 3-dimensional, translationally ordered topologies in the materials. These aspects of the mesogenic block copolymers can be emphasized if, for example, multi-block copolymers — chains with several distinct monomer compositions along its contour length — are swollen,(19) Reference 20 provides a current entry to the literature of mesomorphic block copolymers. 

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