How to Store Purified Terephthalic Acid?

Purified terephthalic acid, as the core monomer of polyester synthesis, is characterized by high-purity carboxyl crystal structure, heat sensitivity and strong hygroscopic tendency. Its storage essence is to inhibit the spontaneous reaction process between the active functional groups of the molecule and the environmental medium.

Purified terephthalic acid can be packaged with multi-layer barrier to build a water vapor diffusion barrier. The aluminum-plastic composite film water barrier layer blocks the penetration of environmental moisture, and the inner bag hot-melt seal eliminates the edge leakage path. The storage environment needs to maintain the dew point below the critical value of crystal moisture absorption to prevent surface dissolution from inducing local hydrolysis reaction.

Because the benzene ring structure stimulates electron transition under light, black light-shielding packaging is more conducive to the storage of purified terephthalic acid. In addition, the storage area needs to eliminate the source of ozone generation to avoid the epoxidation side reaction of unsaturated impurities. It is also necessary to avoid radiant heat sources, and the temperature control system inhibits the lattice reorganization caused by the temperature difference between day and night.