Materials polymeric, self-reinforced

In both cases, pretransltional properties (2), the type of liquid crystalline phase and order parameters (8-9). elastic (Ifl) and rheological properties (11=12) have been the object of numerous studies or review articles. Some applications in very different fields (high modulus fibers, self-reinforced polymeric materials, electronic display devices, non-linear optics, etc.) have already been realized or are being pursued. 

Although composites are a very important class of polymeric materials they form a separate subject in their own right, in which it is necessary to assume an understanding of the properties both of the polymer matrix and of the reinforcing material. They are not discussed further in this book, but it is interesting to note that in some ways semi-crystalline polymers can be considered as self-reinforcing polymers, because the mechanical properties of the crystalline parts are different from those of the non-crystalline parts, which often effectively form a matrix in which the crystals are embedded. 

Kmetty A, B6r4ny T and Karger-Kocsis J (2010) Self-reinforced polymeric materials A review, Pmg Polym Sci 35 1288-1310. 

Polymer-polymer composites or self-reinforced polymeric materials (SRPM) are materials where both the reinforcement and matrix components have been made from all polymeric materials. This can include two polymers coming from the same family of polymers or simply the same polymer. Micro- and nanofibrillar single polymer composites (SPCs) are a subcategory of self-reinforced polymeric materials which are made by combining the properties of molecularly aligned and oriented forms with randomly disoriented forms of the same polymer material. It can be debated whether or not such a material can still be called a composite as it is not made of two or more dissimilar materials. However, one thing is for sure, the two forms of the material can exhibit very different mechanical properties. 

Currently, considerable research activities, accompanied with commercial interest, are devoted to all-polymeric materials, and especially to their self-reinforced versions. In all-polymeric materials, both the reinforcing and matrix components are given by suitable polymers. In single polymeric materials, the same polymer forms both the reinforcing and matrix components. They are also referred to as self-reinforced, single-phase or homocomposites. We prefer to use the term single polymer composite (SPC), albeit, in open hterature, polymer composites, in which the reinforcement and matrix polymers are different, but in the same family, are also called SPCs these composites are not considered in this chapter. The same holds true for those SPC combinations which consist of homo- (reinforcement) and copolymers (matrix) of the same material. Nonetheless, some of the latter composites are covered in this review for the sake of completeness. 

Possible structures which may arise dming the phase separation of binary mixtures have been discussed elsewhere. It is important that the microphase particles evolved in this process, which have different composition and size be considered as quasi-particles of polymeric filler and the system as a whole- as a self-reinforced composite material. Thus polymer-polymer systems with incomplete phase separation may be described as systems consisting of polymeric matrix and polymeric filler. The common feature for both such systems and polymers obtained by the introduction of polymeric filler consists of formation of an interphase zone between two separated coexisting phases. 

Liquid Crystalline Polymer as Self-Reinforcing Fillers for Polymeric Materials... 

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