In this paper, we created nanohybrids consisted of imogolite nanotube and various aliphatic polyesters through a hydrophobization of imogolite. The hydrophobization of imogolite via covalent bonding between aluminol group on imogolite and aldehyde group in benzaldehyde was firstly achieved. The hydrophobized imogolite is well miscible with aliphatic polyester and their mixture forms the transparent films via casting of their chloroform dispersion. An addition of hydrophobized imogolites to aliphatic polyester such as poly(L-lactic acid), poly(epsilon-caprolactone), and poly(butylene succinate) brought about the plasticization of polymer films that should be induced by the miniaturization of polymer crystals via the nucleation of polymer chains on hydrophobized IGs. Especially, the nanohybrids of poly(L-lactic acid) and hydrophobized imogolite showed an oriented crystallization under stretching. (C) 2015 Elsevier Ltd. All rights reserved.