Solid‐state Synthesis of Two Different Polymers in a Single Crystal: Miscible Polymer Blend via Topochemical Reaction

The topochemical synthesis of a miscible polymer‐blend is described here. The azide and alkyne decorated tetrol 1 crystallizes with two different conformers. Both the conformers exhibit self‐sorted head‐to‐tail alignment with proximally placed reacting groups such that topochemical polymerization yields two types of polymer chains each containing only one type of conformers. The orientation of complementary reactive groups in one of the head‐to‐tail‐arranged conformers favors the formation of cis‐triazole linkages and the other favors the trans‐triazole linkages. Crystals of 1 on heating gave a perfect polymer‐blend containing equal amounts of cis‐triazole‐linked and trans‐triazole‐linked polymers. As each conformer is H‐bonded to four conformers of other kind, the polymerization yields a perfect polymer‐blend wherein each polymer chain is surrounded by other type of chains. Thus the molecular ordering in the pre‐polymerized state in a crystal is utilized for achieving a polymer blend.

from A via a.sfakia on Inoreader http://bit.ly/2RzfCxh