Description of PPHT

5-Isobenzofurancarboxamide, N,N'-1,4-phenylenebis[octahydro-1,3-dioxo-] (also known as PPHT or hydrogenated PMDA-p-phenylenediamine bisanhydride equivalent, CAS: 1370585-34-4) is a specialized alicyclic diamide-dianhydride monomer with the molecular formula C??H??N?O?. It serves as a key building block for high-performance polyimides, offering improved solubility, lower color, and enhanced processability compared to aromatic counterparts. PPHT-derived polyimides exhibit excellent thermal stability, mechanical strength, and optical transparency, making them suitable for flexible electronics, aerospace composites, and advanced coatings in demanding environments.

Application of PPHT

?   Monomer for Colorless and Transparent Polyimides. PPHT is a specialized alicyclic diamide-dianhydride monomer used in the synthesis of high-performance polyimides. Its saturated octahydro-isobenzofuran structure reduces charge-transfer interactions, yielding polyimides with excellent optical transparency, low color, and high clarity.

?   Flexible Electronics and Display Substrates. PPHT-derived polyimides exhibit superior solubility, processability, and thermal stability. They are ideal for flexible OLED displays, foldable screens, touch panels, and substrates in smartphones, wearables, and next-generation optoelectronics.

?   Advanced Optical Films and Coatings. The enhanced optical properties make these polyimides suitable for optical waveguides, protective films, and high-transparency coatings requiring low birefringence and excellent light transmission.

?   High-Performance Composites and Insulation. PPHT polyimides offer good mechanical strength, thermal resistance, and dimensional stability. They suit aerospace composites, electronic insulation layers, and materials in harsh environments.

?   Specialty Applications in Electronics. These polyimides provide low dielectric constants and improved processability, making them valuable for semiconductor packaging, flexible printed circuits, and advanced electronic components.

Storage of PPHT

It should be kept in a cool, dry, well-ventilated area at 2–8°C. Keep containers tightly sealed under inert atmosphere (nitrogen or argon) to prevent hydrolysis of anhydride groups and absorption of moisture. Protect from heat, direct sunlight, strong bases, and nucleophiles. Avoid exposure to humidity; use a desiccator or glovebox for handling. Shelf life is typically 12–24 months when stored properly.