We have investigated the stability of a cubic lattice having a periodic-minimal surface in a non-ionic surfactant system using a time-resolved small-angle neutron-scattering technique. The cubic lattice transformed from a hexagonal phase showed a polycrystalline scattering pattern and strong intensity fluctuation as a function of time. A characteristic correlation time of the intensity fluctuation obtained by time correlation function analysis was about 150 min. In the case of the cubic lattice from a lamellar phase the diffraction peaks showed monocrystalline-like pattern and no intensity fluctuation. We consider that the fluctuations arise from the polycrystalline cubic network trapped in a metastable state. In other words, the cubic phase from the hexagonal phase is in an incubation time of finite-to-infinite transition of the cubic network.
- Cubic phase
- Incubation time
- Infinite periodic minimal surface
- Phase transition