Hasegawa, Masatoshi;Fujii, Mari;Wada, Yuriko published 《Approaches to improve the film ductility of colorless cycloaliphatic polyimides》 in 2018. The article was appeared in 《Polymers for Advanced Technologies》. They have made some progress in their research.Application In Synthesis of 3-(4-Aminophenoxy)aniline The article mentions the following:
This study described approaches for improving the film ductility of colorless cycloaliphatic polyimides (PIs). An unexpected toughening effect was observed when a PI derived from pyromellitic dianhydride (PMDA) and 4,4′-methylenebis(cyclohexylamine) was modified by copolymerization with a low isophoronediamine (IPDA) content of 5 to 30 mol%, despite there being no film-forming ability in the homo PMDA/IPDA system. For example, at an IPDA content of 20 mol%, the copolymer showed significantly improved film toughness (maximum elongation at break, εb max = 57%), excellent optical transparency (light transmittance at 400 nm, T400 = 83.7%), and a high glass transition temperature (Tg = 317°C). This toughening effect can be interpreted on the basis of the concept of chain slippage. In this study, the PIs derived from bicyclo[2.2.2]octane-2,3,5,6-tetracarboxylic dianhydride (H-BTA) with various diamines were also systematically investigated to evaluate the potential of H-BTA-derived systems. The combinations of H-BTA with ether-containing diamines led to highly tough PI films (εb max > 100%) with very high Tgs, strongly contrasting with the results of an earlier study. The observed excellent properties are related to the steric structure of H-BTA. Our interest also extended to the solution processability. A copolyimide derived from H-BTA with a sulfone-containing diamine and an ether-containing diamine achieved a very high optical transparency (T400 = 86.8%), a very high Tg (313°C), and good ductility (εb max = 51%) while maintaining solution processability. Thus, these approaches enabled us to dramatically improve the ductility of cycloaliphatic PI films that have, to date, been considered brittle. To complete the study, the researchers used 3-(4-Aminophenoxy)aniline (cas: 2657-87-6) .
3-(4-Aminophenoxy)aniline is one of ethers-buliding-blocks. Ethers lack the hydroxyl groups of alcohols. Without the strongly polarized O―H bond, ether molecules cannot engage in hydrogen bonding with each other. Application In Synthesis of 3-(4-Aminophenoxy)anilineEthers do have nonbonding electron pairs on their oxygen atoms, however, and they can form hydrogen bonds with other molecules (alcohols, amines, etc.) that have O―H or N―H bonds.
Reference:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem