2023 年 27 巻 1-2 号 p. 7-11
Herein, the composition of lithium-exchanged natural smectite and butenediol vinyl alcohol copolymer is varied over a wide range, from 100% clay to 100% polymer. The gas permeability is measured from 40 to 160°C, and the gas permeability behavior is discussed from the perspective of activation energy. The gas permeability is considered using He, which has a gas permeability equivalent to that of hydrogen. The gas-barrier property of the lithium-exchanged smectite is one-seventh of that the purified natural smectite as a clay alone. However, the gas-barrier property of the lithium-exchanged smectite increases as it is mixed with the polymer and becomes equivalent to that of the purified natural smectite composites at some ratios. In other words, depending on the clay and polymer combination, a coating with a dramatically high barrier property can be realized by composing, even if it is not necessarily a combination of the highest-performance clay and polymer. The polymer is the dominant factor in the activation energy of the gas permeation through the composite, which is similar for composites using lithium-exchanged and purified natural smectite.
