Synthesis and Characterization of Semiaromatic Polyimides Containing POSS in Main Chain Derived from Double-Decker-Shaped Silsesquioxane

• Published in: Macromolecules 2007-08, Vol.40 (16), p.5698-5705
• Main Authors: Wu, Shouming, Hayakawa, Teruaki, Kikuchi, Ryohei, Grunzinger, Stephen J, Kakimoto, Masa-aki, Oikawa, Hisao
• Format: Article
• Language: English
• Subjects: Applied sciences; Exact sciences and technology; Inorganic and organomineral polymers; Physicochemistry of polymers; Preparation
• ISSN: 0024-9297; 1520-5835
• DOI: 10.1021/ma070547z

A series of semiaromatic polyimides containing polyhedral oligomeric silsesquioxane (POSS) in main chain (POSS−PIs) from a double-decker-shaped silsesquioxane diamine (DDSQ−diamine) (4) with various aromatic tetracarboxylic dianhydrides were prepared and the structures were characterized by IR and NMR spectra. A double-decker-shaped silsesquioxane dianhydride (DDSQDA) (3) was synthesized by hydrosilylation reaction from double-decker-shaped silsesquioxane (DDSQ) (1) and cis-5-norbornene-endo-2,3-dicarboxylic anhydride (2), which then reacted with 4,4‘-oxydianiline (ODA) to produce the DDSQ-diamine. The POSS−PIs possessed good thermal stability and mechanical properties, low water absorption, and alkali resistance as well as low dielectric constant. The 5% weight loss temperatures (T d 5) in air were observed at 495−514 °C. The polymer films had good mechanical properties with elongation at breakage of 2.9−6.0%, in which POSS−PI 8c derived from 4,4‘-oxydiphthalic anhydride (ODPA) exhibits the highest elongation of 6.0%. The water absorption of POSS−PI 8b (