Poly(<i>N</i>-vinylimidazole)-<i>l</i>-Poly(tetrahydrofuran) Amphiphilic Conetworks and Gels: Synthesis, Characterization, Thermal and Swelling Behavior

Abstract

A novel class of amphiphilic conetworks (APCNs), poly(<i>N</i>-vinylimidazole)-<i>l</i>-poly(tetrahydrofuran) (PVIm-<i>l</i>-PTHF) (“<i>l</i>” stands for “<i>linked by</i>”), was prepared by free radical copolymerization of telechelic PTHF dimethacrylate macromonomer and <i>N</i>-vinylimidazole in ethanol as a suitable cosolvent for all the components. Low amounts of extractables were obtained indicating successful conetwork formation. A series of transparent, macroscopically homogeneous PVIm-<i>l</i>-PTHF conetworks with a wide composition range of 25–89 wt % PTHF were prepared. Investigations by DSC revealed the existence of two distinct glass transition temperatures (<i>T</i>_g) in the vicinity of the <i>T</i>_g of homopolymers proving microphase separation of PVIm and PTHF in these conetworks. Surprisingly, the crystallization of PTHF is strongly suppressed and prevented at lower than 38 wt % PTHF in the presence of the glassy, amorphous PVIm in these APCNs. The amphiphilic nature of the PVIm-<i>l</i>-PTHF conetworks was proved by their uniform swelling in both nonpolar (tetrahydrofuran, carbon tetrachloride) and polar solvents (water, methanol) in a broad composition range, indicating bicontinuous (cocontinuous) phase separation in these novel, unique bicomponent polymeric materials.