Amylose polymeric structure

Figure 2. Schematic of amylose and amylopectin polymeric structure before and after degradation by bacteria or enzymes...

Copolymers with Amylose The combination of oligo- or polysaccharides with non-natural polymeric structures opens up a novel class of materials. By varying the chain topology of the individual blocks as well as of the whole copolymer, the type of blocks, the composition etc. a complete set with tailor-made properties can be designed. 

In the same way, glucose molecules can be connected by a glycosidic bond into long polymeric structures of polysaccharides. The structure of the polysaccharide formed from glucose depends mostly on the starting anomer. Polymerization of a-D-glucopyranose by the a(l,4)-glycosidic bond yields amylose, the polysaccharide which is a component of starch. 

The glycogen phosphorolysis of phosphorylase can be reverted, which makes it possible to enzymatically polymerize amylose as well as hybrid structures with amylose as outlined in the following section. 

In all cases, the authors could successfully elongate the attached oligosaccharide structures using enzymatic polymerization, the product being comb-type block copolymers with amylose. 

Even though the products are not block copolymer structures, the work of Kadokawa and colleagues should be mentioned here. In a process that the authors named vine-twining polymerization (after the way that a vine plant grow helically around a support rod), the enzymatic polymerization of amylose is performed in the presence of synthetic polymers in solution, and the authors showed that the grown amylose chains incorporate the polymers into its helical cavity while polymerizing [184-191]. 

The most useful CSPs for the resolution of many varied, structurally different racemates are the following the peracetates, benzoates (and derivatives) and carbamates (and derivatives) of cellulose and amylose coated on wide pore silica gel. Some of these polymer derivatives are also potentially useful as pure polymeric bead material, but mainly for preparative purposes. 

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