A novel super thermal insulation material: bamboo-like polymer nanotubes

One-dimensional nanomaterials have widely applied in the fields of energy conversion and storage due to their exceptional performance because of the nano-size effect. Herein, we synthesized bamboo-like polymer nanotubes based on cationic polymerization using immiscible initiator nanodroplets that results in a hollow structure. The suspended microelectrode is fabricated to measure the axial thermal conductivity of a single polymer nanotube, which demonstrates that this hollow structure can reduce its effective thermal conductivity. The experimental results show that its effective thermal conductivity is close to 0.03 W m^-1 K^-1, and decreases to 0.02 W m^-1 K^-1 with increasing temperature of the heating microelectrode, which may be due to the increasing lattice vibration and inelastic scattering between phonons. Its effective thermal conductivity is smaller than that of air, indicating that the synthetic method is an effective way to fabricate thermal insulating polymer nanotubes by significantly lowering the effective thermal conductivity. Hence, the method offers a new strategy in the fields of thermal insulation and protection.