Molecular Recognition in a Thermoplastic Elastomer

Selective incorporation of bisurea guests in thermoplastic elastomers with poly(tetrahydrofuran)
soft blocks and bisurea containing hard blocks is observed when the distances between the urea groups
of host and guest match. The incorporation leads to significant modulation of mechanical properties. With
bisurea-functionalized dyes as guests, a strong difference in extractability by detergent solution was shown
between dyes differing by just one methylene unit between urea groups. Upon elongation of elastomer
films, strong differences in alignability of matching and nonmatching dyes were observed.