Synthesis and properties of multi-block semi-alicyclic polyimides for thermally stable transparent and low CTE film

Investigations on the polyimides derived from unfunctionalized symmetric cyclopentyl‐containing alicyclic cardo‐type dianhydride

“…Actually, CTC plays an important role in offering the interchain locking force, so stronger CTC leads to greater dimension stability. It is recently reported that by enlarging the electron‐donating properties using alicyclic diamine and coupling with rigid electron‐accepting aromatic dianhydride partner, CTE of PI could be lowered to be comparable to that of copper foil . Relatively high CTE results of CPI series in this work are, in a degree, associated with the decreased CTC of PIs containing Cardo structure and ester linkage.…”

Recent Trends on Transparent Colorless Polyimides with Balanced Thermal and Optical Properties: Design and Synthesis

“…Monomer sequence in the PI chain also control the compatibility between chains, thereby leading to different film microstructures, which originates various properties . By comparison of the different copolymerization methods between BPDA, t‐CHDA and 2,5(2,6)‐bis(aminomethyl) bicycle[2.2.1]‐heptane, it is found that block method is more effective to minimize the CTE and enhance the film strength, meanwhile maintaining high transparency, which may be attributed to the micro‐phase separation . The CBDA/AB‐TFMB PI system (Scheme ) offers no chemical imidization (CI) process compatibility because of its poor solubility.…”

“…[98,[196][197][198] By comparison of the different copolymerization methods between BPDA, t-CHDA and 2,5(2,6)-bis(aminomethyl) bicycle[2.2.1]-heptane, it is found that block method is more effective to minimize the CTE and enhance the film strength, meanwhile maintaining high transparency, which may be attributed to the micro-phase separation. [98,199] The CBDA/AB-TFMB PI system (Scheme 16) offers no chemical imidization (CI) process compatibility because of its poor solubility. CI is important to get colorless PI film.…”

Synthesis and Properties of Cost-Effective Light-Color and Highly Transparent Polyimide Films from Fluorine-Containing Tetralin Dianhydride and Aromatic Diamines

“…have been performed to develop light-color PI optical films [6]. Among various light-color PI films, the semi-alicyclic ones derive from alicyclic dianhydrides and aromatic diamines usually possess the best comprehensive properties, including good optical transparency, good thermal stability, and acceptable mechanical properties [7]. For instance, recently, Hasegawa and coworkers developed a series of colorless and transparent semi-alicyclic PI optical films from hydrogenated pyromellitic dianhydride (HPMDA) and aromatic diamines [8,9].…”