Jin, Ke;Sun, Qiangsheng;Feng, Yudi;Guo, Jia;Xu, Jiangtao;Wang, Changchun published 《Significant Influence of Alkyl Substituents in the Alicyclic Rigid Backbone on Solubility and Thermal Stability of Polyarylamide Copolymers》 in 2021. The article was appeared in 《ACS Applied Polymer Materials》. They have made some progress in their research.Safety of 3-(4-Aminophenoxy)aniline The article mentions the following:
Incorporation of alicyclic structural units in a polymer backbone holds great promises for preparing polyarylamides with superior phys. properties (solubility, optical transparency, thermal stability, etc.). In this study, the alicyclic-containing building block, tetraethyl-substituted dibenzocyclooctadiene (TE-DBCOD), was integrated into the backbone of polyarylamides through a unique diamine monomer, TE-DBCOD-NH2. The TE-DBCOD-containing polyarylamides were synthesized first through polycondensation with different contents of TE-DBCOD units. Compared to the control polymers without DBCOD or Et side-chain units, the polyarylamides with TE-DBCOD units showed better solubility in less polar solvents (m-cresol, pyridine, and tetrahydrofuran) and higher glass transition temperature (Tg), which provides an opportunity to fabricate polyarylamides with both improved solubility and Tg. Meanwhile, we also prepared the poly(amide-imide)s with TE-DBCOD by a two-step method for comparison. In contrast, the aromatic poly(amide-imide)s showed better solubility and lower Tgs than the corresponding aromatic poly(amide-imide)s without TE-DBCOD contents, which revealed the complex influence of structure parameters on different polymers. Addnl., the synthesized polymers possessed high thermal stability (5% weight loss temperature > 440°C) verified by thermogravimetric anal. The strategy of introducing short side chains in polymer backbones opens a window for exploration of polymers with improved solubility and increased Tg simultaneously, which also facilitates the understanding of the structure-property relationship of polymers with alicyclic structural units. And 3-(4-Aminophenoxy)aniline (cas: 2657-87-6) was used in the research process.
3-(4-Aminophenoxy)aniline is one of ethers-buliding-blocks. Ethers feature bent C–O–C linkages. In dimethyl ether, the bond angle is 111° and C–O distances are 141 pm. The barrier to rotation about the C–O bonds is low. Safety of 3-(4-Aminophenoxy)aniline The bonding of oxygen in ethers, alcohols, and water is similar. In the language of valence bond theory, the hybridization at oxygen is sp3.
Reference:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem