Synthesis and Characterization of Hyperbranched Aromatic Poly(ether imide)s

Abstract

The four AB2 monomers, N-[3-or 4-bis(4-hydroxyphenyl)toluoyl]-4-chlorophthalimide and N-{3-or 4-[1,1-bis(4-hydroxyphenyl)]ethylphenyl}-4-chlorophthalimides, were prepared and used for synthesis of hyperbranched poly(ether imide)s bearing hydroxyl end groups. These hyperbranched poly-(ether imide)s had moderate molecular weights with broad distributions and showed glass-transition temperatures (T gs) between 177 and 230 °C. The thermogravimetric analytic measurement revealed the decomposition temperature at 5% weight-loss temperatures (Td 5% ) ranging from 240 to 281 °C. Analysis using 1 H NMR spectroscopy revealed the four types of hyperbranched poly(ether imide)s to have similar degrees of branching (ca. 60%). These polymers were modified by acylation or nucleophilic substitution reaction at the hydroxyl end groups. The conversion effectiveness depended on the type of modification reaction, modifier, and reaction conditions. The thermal stability and solubility of hyperbranched poly-(ether imide)s were improved by the modification of the end groups.

Facile and efficient preparation of phosphinate‐functionalized aromatic diamines and their high‐Tg polyimides

“…These results seem conflict with our speculation, but actually they are not. Supporting Information Scheme S1 shows the possible mechanism of stabilization of carbocation in the work of Shu and coworkers30 and Li et al31 As in Supporting Information Scheme S1, after one phenol reacted with the carbonyl group of 4‐nitroacetophenone, the resulting carbocation was stabilized by the phenolic‐OH. Since the resonance between the phenolic‐OH and the carbocation stabilized the carbocation, the electrophilic substitution of second phenol on the carbocation proceeds.…”

“…Generally, bisphenols29–33 and diamines33–36 could be prepared by acid‐catalyzed condensation of ketone or aldehyde compounds with excess phenol or aniline. Ketone/aldehyde compounds with35, 36 or without29, 32–34 the electron‐donating phenolic‐OH or amino groups can carry out the reaction.…”

Colorless and high organosoluble polyimides from 2,5-bis(3,4-dicarboxyphenoxy)-t-butylbenzene dianhydride and aromatic bis(ether amine)s bearing pendent trifluoromethyl groups

“…By introducing the ether chain [6][7][8] or bulky group [9,10], the aromatic polyimide can raise the flexibility of polymer, reduce the melting point or the glass transition temperature, and modify solubility while maintaining the thermomechanical properties. For optical applications, a number of very lightly colored to colorless transparent polyimide films have been synthesized and characterized.…”

High‐Tg Transparent Poly(ether sulfone)s Based on Phosphinated Bisphenols

“…Generally, the bisphenols [32][33][34][35][36] could be prepared by acid-catalyzed condensation of ketone or aldehyde-containing compounds with excess phenol. However, only symmetric bisphenols can be obtained by that approach.…”