Zigzag chains synthetic structures

From the viewpoint of synthetic polymer chemistry, although the formation of stereospecific polymers (isotactic and syndiotactic) is very popular, the present polymer is the first example having a double syndiotactic structure. In ad tion, the polymer consists of an alternating zigzag-linear main chain structure. 

Not all polymer chains can be crystallized only those with stereoregularity can. For example, polyethylene can be crystallized because there is a regular configuration inherent in the monomer. Polypropylene, on the other hand, can be crystallized only under certain conditions. The crystal structures of these two polymers are also quite different. The former is packed in a zigzag form, whereas the latter has helical content (not, of course, 100%). We select these two polymers to illustrate the crystal structure, if any, of synthetic polymers. 

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