Amide—Imide Polymers

Ch1orocarhony1trime11itic acid 1,2-anhydride [1204-28-0] (9), is used in the preparation of esters and amide—imide polymers. TriaHyl trimellitate [2694-54-4] (10) is used as a cross-linking or co-curing agent for ethylene-derived mbbers and plastics. 

Figure 2. The dipole moment of the absorbed water molecules varies from approximately 1.8 to 0.9 for the polyimides and from 1.1 to 0.7 for the polyamide-imides corresponding to fractional polarizabilities of l.O/i -0.4/x. The low values of p (<0.5p ) as seen in all the amide-imide po ymers and several of the ° polyimides, indicate restricted mobility of the water molecules. In the amide-imide polymers, we believe this is due to increased water-polymer interactions such as hydrogen bonding. Other evidence of hydrogen bonding in polyamide-imides is the water-induced plasticization and Tg lowering frequently observed.

G. T. Brooks and R. E. Bockrath. Injection moldable amide-imide polymers and copolymers containing metal oxides capable of forming hydrates stable at temperatures in excess of 500.degree. f. US Patent 4403 061, assigned to Standard Oil Company (Indiana) (Chicago, IL), September 6, 1983. 

Al n. Abbreviation of amide-imide (polymer). See polyamide-imide resin. 

Amoco Amide-Imide Polymers", Technical Bulletin AM-1, Amoco Chemical Corp., USA. 

Al n Abbreviation of AMIDE-IMIDE (polymer). See Polyamide-Imide Resin. 

Figure 1.3 Chemical structures of the monomers, polyfether amide) fit polyfether amide-imide) polymers and their copol)miers. Reproduced from reference 2 with permission from Elsevier.

Amide-imide polymers N,N-Azobisisobutyronitrile Angora wool (DIN)... 

Poly(amide-imide) is the condensation polymer of 1,2,4-benzenetricarboxylic anhydride and various aromatic diamines and has the general structure ... 

Copoly(amide-imides) comprise an important class of copolyimides that have been developed into a commercial product. Incorporating the amide linkage into the PI makes the polymer more tractable than simple Pis, but involves a loss in thermal stabiUty. However, copoly(amide—imides) still possess quite good thermal stabiUties, intermediate between those of polyamides and Pis (12). They are relatively inexpensive to synthesize. 

Polymers based on trimellitic anhydride are widely used in premium electromagnetic wire enamels requiring high temperature performance. Several types of trimellitic anhydride-derived polymers are used as wire enamels poly(amide—imide)s (133), poly(ester—imide)s (134), and poly(amide—imide— ester)s (135). Excellent performance characteristics are imparted by trimellitic anhydride-based polymers for wire enamel requirements of flexibiUty, snap, burnout, scrap resistance, heat shock, and dielectric strength. 

Modification of cellular polymers by incorporating amide, imide, oxa2ohdinone, or carbodiimide groups has been attempted but only the urethane-modified isocyanurate foams are produced in the 1990s. PUIR foams often do not require added fire retardants to meet most regulatory requirements (34). A typical PUIR foam formulation is shown in Table 6. 

Polyamide Imides. Polyamide imides (PAIs) are formed from the condensation of trimellitic anhydride and aromatic diamines (33). The polymer is called amide—imide because the polymer chain comprises amide linkages alternating with imide linkages, with the general chemical stmcture ... 

Poly (2,4-d if luoro-1,5, pheny lene t r ime 11 i t ic amide-imide) was prepared by a two-step procedure 12 At the first step, the polyamic acid was prepared by reacting 2,4-difluoro-1,5-phenylene diamine with trimellitic anhydride acid chloride (with the mole ratio of one to one) in anhydrous N,N-dimethylacetaraide at room temperature under nitrogen. After reaction, the polymer was poured into water and precipitated. After filtration, the white solid was washed with distilled water and dried in a vacuum oven. The poly(amide-imide) was obtained from heating the polyamic acid at 220°C for 3 hours. The polyamic acid was dissolved in N,N-dimethyl acetamide or N,N-dimethyl forraamide, cast on glass plates, and the solvent evaporated in a vacuum oven to form a polyamic acid film before heating at 220°C. 

The chemical structures of these polymers were characterized using FT-IR. Poly(1,3-phenylene isophthalamide) (PMI) and poly (2,4-difluoro-l,5-phenylene isophthalamide) (2,4-DIF-PMI) shoved N-H stretching bands at 3400-3200 cm l and C==0 stretching bands(amide I) at 1630-1650 cm-. Poly(2,4-difluoro-1,3-phenylene trimellitic amide-imide) (2,4-DIF-PMTAI) showed additional bands at 1740 and 1796 cm l corresponding to imide C==0 stretching band at 1625 cif and C-0-C stretching bands at 1255 and 1050 cm l. 

As part of an effort to develop high-performance, high-temperature-resistant polymers for microelectronics applications, we also recently described a series of both partially fluorinated and nonfluorinated poly(aryl ether ketone)s containing amide, amide-imide, cyano oxadizole, or pyridazine groups and characterized their thermal and electrical properties.11... 

Fig. 18.6 Upper part - chemical structures of poly(oxyethylene)-segmented (POE) and amides and imides polymer derivatives (POEM). Lower left part - chemical structure of 15-crown-5-functionalized MWCNT. Lower right part - chemical structure of l-(2-acryloyloxy-ethyl)-2-methyl-benzoimidazol-l-ium iodide (AMIml).

Poly(phenylquinoxaline—amide—imides) are thermally stable up to 430°C and are soluble in polar organic solvents (17). Transparent films of these materials exhibit electrical insulating properties. Quinoxaline—imide copolymer films prepared by polycondensation of 6,6,-methylene bis(2-methyl-3,l-benzoxazine-4-one) and 3,3, 4,4 -benzophenone tetracarboxylic dianhydride and 4,4,-oxydianiline exhibit good chemical etching properties (18). The polymers are soluble, but stable only up to 200—300°C. 

POLYIMIDES. These are heat-resistant polymers which have an imide group (—CONHCO-) in the polymer chain, Polyimides, poly(amide-imides), and poly(esterimides) are commercially available,... 

Blaschke et al. [54—56] synthesized polyacrylamide and polymethacrylamide containing chiral side chains. In order to make CSPs, these polymers were bonded to silica gel chemically [54-56]. The CSP obtained by /V-acrylol-(.S)-phenylalanine ethyl ester was commercialized by Merck Chemical Company by the trade name ChiraSpher. The racemic compounds resolved are those capable of forming hydrogen-bondings (i.e., amides, imides, carboxylic acids, and alcohols). It has been reported that nonpolar solvents like benzene and toluene individually or their mixtures were the best mobile phases. In addition to these CSPs, other amide CSPs were prepared and tested for the chiral resolution [57,58]. 

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