文摘
We present a novel type of 鈥渞od鈥揷oil鈥?graft copolymer containing a polyphenylene backbone linked with poly(ethylene oxide) (PEO) side chains. Such graft copolymers manifest unprecedented temperature-dependent one-dimensional (1D) and two-dimensional (2D) self-assembly in solution. At 20 掳C, which is higher than the crystallization temperature (Tc) of the PEO chains, the achiral graft copolymers self-organize into nanoribbons that twist into 鈭?0 渭m ultralong helices with controlled pitch depending on the grafting ratio of the PEO chains. At 10 掳C, which is lower than the Tc, quadrangular multilayer sheets of over 10 渭m in lateral size are obtained. To our knowledge, this work presents the first example of controlled self-assembly of graft polymers into 1D helix and 2D sheet superstructures.