Time evolution behavior is described for a transient network formed via hydrogen bonds in a random copolymer of vinyl acetate and vinyl alcohol. As the cross-link density depends on temperature, the storage modulus G′ of the system slowly evolves toward equilibrium at the experimental temperature, Ta, after changing the temperature from higher or lower than Ta. The ‘memory effect’ (the structure developed at a certain temperature is preserved after changing the temperature) found in the system is discussed in detail.
- Osamu Urakawa
- Azusa Shimizu
- Tadashi Inoue
