Liquid-crystalline polyimides. 3. Fully aromatic liquid-crystalline poly(ester imide)s derived from N-(4-carboxyphenyl)trimellitimide and substituted hydroquinones

Soluble Polyimides from a New Dianhydride: 5′‐tert‐Butyl‐m‐terphenyl‐3,4,3″,4″‐tetracarboxylic Acid Dianhydride

“…80 8C/ 0.01 mmHg. 1 (5) 5 was prepared from triethyl borate and 3,4-dimethylbenzyllithium by a method reported previously. [7] 3,4-Dimethylbenzyllithium was prepared from 3,4-dimethylbromobenzene, which in turn had been prepared from 3,4-dimethylaniline.…”

“…Therefore, many efforts have been done to make polyimides more tractable, mainly by modification of their chemical structure. Thus, copolyimides have been described which can be processed from the melt or from solution in organic solvents, for instance, poly(ester-imide)s, [1] poly(etherimide)s, [2][3][4] and poly(amide-imide)s. [5] They generally show flexible linkages between the aromatic rings of the main chain, or a combination of different monomers, which provides molecular disorder, lower transition temperatures, and better solubility in organic solvents.…”

New polymers syntheses. 104. Synthesis of poly(ester-imide)s from nylon 6, nylon 11, or nylon 12

“…This is an interesting result because only few noncrystalline thermotropic copolymers have been reported in the literature. [7][8][9][10][11][12] Furthermore, it should be mentioned that the nematic and isotropic melts of all co-PEIs having diphenol/4HBA ratios of 1/2 or 1/3 were never perfectly homogeneous. Small fraction of crystallites consisting of 4-HBA blocks were observed in all cases.…”

Tailoring of polymer properties by the synthesis of multiblock copolymers

“…The first one was poly(ethyleneterephthalate-co-oxybenzoate), PET/HBA, known from Jackson and Kuhfuss [15] with a low Tg region below 100 °C. The second one contained basically the same units, except that the HBA units were replaced by N-(4-carboxyphenylene)-4,4'-(carboxyphenoxy)-phthalimide and t-butylhydroquinone, as described by Kricheldorf et al [16,17], having a Tg quite close to polysulfone, thus increasing the rigidity of the amorphous phase. The Tg behavior of the MBCP (Fig.…”