Synthesis and properties of new aromatic polyimides containing spirocyclic structures

• Published in: Polymer (Guilford) Vol. 137; pp. 283 - 292
• Main Authors: Terraza, C.A., Tagle, L.H., Santiago-García, J.L., Canto-Acosta, R.J., Aguilar-Vega, M., Hauyon, R.A., Coll, D., Ortiz, P., Perez, G., Herrán, L., Comesaña-Gándara, B., McKeown, N.B., Tundidor-Camba, A.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 14.02.2018; Elsevier BV
• Subjects: Aromatic polyimides; Casting; Gas separation membranes; Gas transport; Microporosity; Organic solvents; Permeability; Polyimide resins; Polymer of intrinsic microporosity; Polymers; Robustness (mathematics); Solvents; Studies; Synthesis; Thermal decomposition; Thermal stability; Thin films; Gas separation membranes; Aromatic polyimides; Polymer of intrinsic microporosity
• ISSN: 0032-3861; 1873-2291
• DOI: 10.1016/j.polymer.2018.01.013

The synthesis of three novel aromatic polyimides (PIs) containing spiro units is described. These PIs are soluble at room temperature in most common organic solvents, facilitating their processability. Additionally, they are highly thermally stable, with thermal decomposition temperatures (Td10%) over 500 °C, and had moderately high Tg values between 230 and 265 °C. Robust self-standing thin films were prepared from these polyimides, via the solution casting method, which were suitable for gas transport measurements. The relatively low permeability and selectivity of these PIs, as compared to Polymers of Intrinsic Microporosity (PIMs) that also contain spirocyclic structures, demonstrate the importance of restricting rotation within the polymer chain, which is a key structural feature of the PIMs. [Display omitted] •Three new aromatic polyimides containing spirocyclic moieties were obtained and evaluated as gas separation membrane.•The spirocyclic unit is responsible for the good solubility of the polymers, minimizing the cohesive forces between chains.•The requirements of total chain rigidity is mandatory for attaining polymers with high permeability and selectivity.