Nicotinic-based poly(amide-ether-imide)s: a new category of soluble, heat-resistant, and flame-retardant polyimides

Abstract

A novel fully aromatic diamine containing highly pyridine units, amide, and ether groups was prepared via two-step reactions: nucleophilic substitution reaction of 2,6-diaminopyridine with 6-chloronicotinoyl chloride led to preparation of a dichloro-diamide compound. Subsequent reaction of this compound with 5-amino-1-naphthol resulted in synthesis of the particular diamine. After complete characterization, polycondensation reaction of the diamine with different dianhydrides led to preparation of related poly(amide-ether-imide)s. The polymers were characterized and their physical and thermal properties including viscosity, solubility, water absorption, thermal behavior and stability, flame retardancy, and crystallinity were studied. The nicotinic-based poly(amide-ether-imide)s showed high heat and flame resistant, low water absorption in conjunction with improved solubility in polar solvents.

Phosphonated polyimides: Enhancement of proton conductivity at high temperatures and low humidity

“…However, random copolyimides were prepared successfully using "two-step" method, as shown in Scheme 2. This method is widely used in the literature for preparation of polyimides form various monomers using either chemical or thermal cyclization dehydration procedures [47][48][49]. In the first step, dark red viscous solution of poly (amic acid) was obtained which was poured dropwise into a large excess of methanol to precipitate a brown solid.…”

Silicon-containing poly(amide-imide)s: preparation, characterization, and properties

“…Thus, the major structural alterations to get processable polymers have been carried out by introducing flexible spacers and also bulky substitutes such as pendent aryl rings into their chains. [13][14][15][16][17] Poly(amide-imide)s can be synthesized by polycondensation from different monomers containing anhydride, carboxylic acid, or aromatic amino groups. To prepare poly(amide-imide), it is common to use a dicarboxylic acid, dianhydride, diamine, amino acid, or anhydride acid, among which trimellitic anhydride (TMA) is a commercially accessible aromatic anhydride.…”

Effect of sepiolite nanoparticles on the properties of novel poly(sulfone ether imide)

“…Among such advantageous properties of aromatic PIs, excellent thermal stability is absolutely their main characteristic arising from the very strong intermolecular interactions between imide functional groups as well as intramolecular π–π stacking between aromatic units . However, common aromatic PIs have very low solubility and relatively high glass transition temperature (T g ) that limiting their processability, and hence their potential for versatile applications in various industrial fields, becomes restricted because ease of solution or melt processing is of great importance in the industries . Introduction of bulky, flexible, or polar functional groups might alleviate this difficulty to a considerable extent .…”

“…[3] However, common aromatic PIs have very low solubility and relatively high glass transition temperature (T g ) that limiting their processability, and hence their potential for versatile applications in various industrial fields, becomes restricted because ease of solution or melt processing is of great importance in the industries. [3,6] Introduction of bulky, flexible, or polar functional groups might alleviate this difficulty to a considerable extent. [7][8][9][10] Therefore, synthesis of PIs containing such functional groups along their main chains or within their side chains is the most frequently used method to tailor their properties.…”