Green Synthesis of Soluble Polysilsesquioxane with Phthalimide Groups

Area of Science:

• Polymer Chemistry
• Materials Science
• Organic Synthesis

Background:

• Polysilsesquioxanes are hybrid organic-inorganic polymers with tunable properties.
• Incorporating functional groups like phthalimide can impart specific characteristics.
• Developing efficient and environmentally friendly synthesis routes is crucial.

Purpose of the Study:

• To synthesize a soluble polysilsesquioxane with pendant phthalimide groups (PSQ-PhI).
• To characterize the structure, molecular weight, and thermal properties of the synthesized polymer.
• To evaluate the potential of PSQ-PhI for applications such as coatings.

Main Methods:

• Solvent- and catalyst-free hydrolytic polycondensation of 2-[3-(triethoxysilyl)propyl]-1H-isoindole-1,3(2H)-dione.
• Characterization using NMR (1H, 13C, 29Si), FTIR, GPC, TGA, DLS, XRD, and elemental analysis.
• Analysis of molecular weight distribution, thermal stability, and structural order.

Main Results:

• Successful synthesis of soluble polysilsesquioxane containing phthalimide groups (PSQ-PhI).
• Characterization confirmed the polymer structure with an average molecular weight of 11,200 Da and a narrow polydispersity index (1.10).
• PSQ-PhI demonstrated good thermal stability (Td5% at 345 °C) and transparency in the visible spectrum.

Conclusions:

• A novel, soluble phthalimide-functionalized polysilsesquioxane was efficiently synthesized via a green route.
• The polymer exhibits desirable thermal stability and optical properties.
• The synthesized PSQ-PhI is a promising material for transparent coatings and other advanced applications.