Hyperbranched polymer liquid-crystal

Monomers of die type Aa B. are used in step-growth polymerization to produce a variety of polymer architectures, including stars, dendrimers, and hyperbranched polymers.26 28 The unique architecture imparts properties distinctly different from linear polymers of similar compositions. These materials are finding applications in areas such as resin modification, micelles and encapsulation, liquid crystals, pharmaceuticals, catalysis, electroluminescent devices, and analytical chemistry. 

Branching in polymers generally reduces the crystallization tendency for conventional polymers. Therefore, hyperbranched polymers were first believed to behave as amorphous polymers due to the highly branched backbone. Several papers have, however, shown that both liquid crystalline and crystalline hyperbranched polymers can be made from some special A B monomers or by attachment of crystallizable end groups. 

Hyperbranched polymers are often referred to as amorphous polymers since the branching of the backbone reduces the ability to crystallize in the same manner as linear polymers. Some exceptions have, however, been presented where the polymers have been modified to induce liquid crystallinity [34,35] or crystallinity [36] (Sect. 3.6.1). 

We are currently initiating three research projects that include (1) the synthesis of reflective liquid crystal/polymer composite films, (2) a study of microphase separation in hyperbranched block copolymers, and (3) the design and synthesis of polar organic thin films, which is the subject of this proposal. (47 words aim for 41 words)... 

As noted above, various morphologies have been documented for dendritic and hyperbranched liquid crystal polymers, and this topic has recently received intense interest [ 14-27, 62-70]. Although the exhaustive revision of this area is outside the scope of this article, several types can be easily identified ... 

Hyperbranched polymers have been used to make unimolecular micelles and novel liquid crystals (see below for a discussion of liquid crystals). A major advantage of hyperbranched systems is that their synthesis is a single step It seems likely that for some applications, hyperbranched systems will perform well, but for others, the precision of a dendritic system will be required. 

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