Polymers transtactic

A cistactic polymer is a tactic polymer in which the main chain double bonds of the configurational base units are entirely in the cis arrangement. A transtactic polymer is a tactic polymer in which the main chain double bonds of the configurational base units are entirely in the trans arrangement [134]. Geometrical cis-trans isomerism also arises from different configurations of substituents on a cyclic structure. 

Figure 4. DSC curves for PMCS-4 (Table 2.3) of various stereo regular structure 1 - atactic, 2, 2 - transtactic polymer 2 (2- heating, 2 - cooling) 3 - heating of polymer 3 4—heating of polymer 4...

When all of the double bonds in the polymer molecule have the same configuration, the result is two different ordered polymer structures—transtactic and cistactic. Figure 8-5 shows the structures of the completely cis and completely trans polymers of isoprene. The stereochemistry of these polymers is indicated in their names. For example, the trans polymer (IX) is named as trans-1,4-polyisoprene or poly( -l-methylbut-l-ene-l,4-diyl). The first name is the IUPAC-recommended trivial name the second name is the IUPAC structure-based (Sec. l-2c) [IUPAC, 1966, 1981, 1996],... 

Moraglio, G., Polizzotti, G. and Danusso, F. Enantiotropic polymorphism of transtactic poly-1,3-butadiene, Europ. Polymer J. 1, 183 (1965)... 

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