3,3 ,4,4 -Benzophenone dianhydride

The polyamic acids were prepared from 3,3 ,4,4-benzophenone dianhydride (sublimed) and 2,3,5,6-tetramethyl-l,4-phenylene diamine in Cold Label N,N-dimethyl formamide (DMF). All chemicals were obtained from Aldrich. A solution of the anhydride was added over 30 minutes to a solution of the amine with stirring under N2 at room temperature at a net concentration of 15% solids. In general, a slight (1%) excess of the anhydride was needed to give maximum viscosity. 

Diisocyanate and acid dianhydride are mixed in equimolar amounts, often previously dissolved in a suitable solvent. 3,3, 4,4 -Benzophenone dianhydride (4,4 -BTDA) is mixed at room temperature with in diphenyl-methanediisocyanate using AW-dimethylformamide (DMF) as a solvent and subsequently heated in vacuum up to 210°C. A PI with a molecular... 

Benzoate 2-naphthoate ethylene, 357 Benzoic acid, 393, 396, 398 Benzonitrile, 263, 286, 318 Benzophenone, 223, 312 3,3, 4,4 -Benzophenone dianhydride, 477, 481 3,3, 4,4 -Benzophenone tetracarboxylic dianhydride, 494 1 -B enzothiazol-3 -phenyl-pyrazoline, 32 Benzotriazole, 317... 

Although this polyimide from benzophenone dianhydride and tetramethyl phenylene diamine exhibits some photosensitivity, it is extremely slow. Profitable directions for improvement would be increasing the photospeed and the solubility in organic solvents. Other areas important for materials to be used as dielectrics include the coefficient of thermal expansion, the moisture uptake, and the dielectric constant. 

Whang and Wu [3] have described the liquid crystalline state of polyimide precursors and shown that certain polyamic acids derived from pyromellitic anhydride exhibit lyotropic behaviour. Liquid crystal phases have also been observed by Wenzel et al. [4] in polyimides derived from pyromellitic anhydride and 2,5-di-n-alkoxy-1,4-phenyl ene diisocyanate. Dezern [5] has disclosed a synthesis for linear polyamide-imides derived from benzophenone dianhydride but the occurrence or otherwise of mesophases is not mentioned. 

PEIs derived from benzophenone dianhydride and linear amino acids (9) generally give isotropic melts with most aromatic phenols, excepting 4,4 -bisphenol [22]. 

The solubility of PNI based on l,3-bis(l,8-dicarboxynaphthoyl)benzene dianhydride is almost identical to that of PNI prepared from 4,4 -bis(l,8-dicarboxynaphthoxy-4)benzophenone dianhydride. Contrary to the DNTA-based PNI [14], para isomeric... 

Pis commonly have been synthesized from reactions of pyromellitic dianhydride [26265-89-4] (PMD A) or 3,3H,4 -benzophenone tetracarboxyUc dianhydride [2421-28-5] (B IDA) with a number of diamines like 2,2-bis(4-aminophenyl)propane, 2,2-bis(4-amino-3-methylphenyl)propane, I,I-bis(4-aminophenyl)-I-phenylethane, and 1,1-his(4-amino-3-methy1pheny1)-1-phenylethane (5). The PMDA-based Pis were thermally more stable than the corresponding Pis obtained from BTDA. 

Poly(phenylquinoxaline—arnide—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 -meth5lene bis(2-methyl-3,l-benzoxazine-4-one) and 3,3, 4,4 -benzophenone tetracarboxyUc dianhydride and 4,4 -oxydianiline exhibit good chemical etching properties (18). The polymers are soluble, but stable only up to 200—300°C. 

Two polymers have been prepared with the benzophenone tetracarboxylic dianhydride (BTDA) and either bis-l,3-(4-aminophenoxy)-benzene or bis-l,3-(4-aminophenoxy)-2-cyano-benzene (Fig. 5.6). Both polymers are soluble in NMP and their Tg values are respectively 191 and 243°C.59... 

Bottle waste, hydrolysis of, 564 Bottles PET, 21 recycled, 532 Branched polymers, 8 Branching, 13 Branching agents, 8 Branching sequence distributions, 446 Brill temperature, 142 Brominated epoxy reagents, 414 Bromination-lithiation, 354 BTDA. See 3,3, 4,4 -Benzophenone-tetracarboxylic dianhydride (BTDA)... 

Benzophenone process, 73 583 Benzophenonetetracarboxylic dianhydride (BTDA), 70 406, 407t Benzophenone trifluoroborane, 4 1441 Benzopyran Red, colorant for plastics,... 

Polyimides derived from 3,3, 4,4 -benzophenone tetracarboxylic acid dianhydride (BTDA), I, and 3,3 -diaminobenzophenone (m,m -DABP), IIA, 4,4 -diaminobenzophenone (p,p -DABP), IIB, or 4,4 -oxydianiline, IIC, (and to which have been added numerous metal compounds) have been prepared. The synthetic procedure em-... 

High adhesive polyimide films were prepared by Kaneshiro et al. (2) consisting of 2,2-bisaminophenoxylphenylpropane and paraphenylene diamine, pyro-mellitic dianhydride, and 3,3, 4,4 -benzophenone tetracarboxylic dianhydride. 

As can be seen from Table 3.1, polyimides based on 4,4 -diaminobenzophenone and common dianhydrides of tetracarboxylic acids (those of pyromellitic, diphenyloxide-3,3, 4,4 -tetracarboxyhc and benzophenone-3,3, 4,4 -tetracarboxylic acids) possess good thermal properties. However, when in their cyclised forms they are practically insoluble in organic solvents, which restricts the possibility of their investigation, processing and use. 

To improve the solubility of polyimides, Korshak and co-workers used l,l-dichloro-2,2-bis(4-aminophenyl)-ethylene as the starting nucleophile [17] (Scheme 3.2). The resulting polymers turned out to be of relatively high molecular weight (r = 1.2-1.4 dl/g), heat resistant > 270 °C) and fire resistant (oxygen index (OI) = 36-39) (Table 3.2). Polypyromellitimide was soluble in H2SO4 only, but polyimides based on the dianhydrides of benzophenone-3,3, 4,4 -tetracarboxylic acid and diphenyloxide-3,3, 4,4 -tetracarboxylic acid were also soluble in w-cresol and a trichloroethane (TCE)/phenol (3 1) mixture. Diphenyloxide-3,3, 4,4 -tetracarboxylic acid was soluble even in N-methyl-2-pyrrolidone (NMP) (Scheme 3.2). 

Polyimides with better viscosity characteristics have been obtained from 3,3 -diamino-4,4 -bis(dimethylamino)-benzophenone and different aromatic tetracarboxylic acid dianhydrides [21] (Scheme 3.4). 

Reactions of 3,3 -diamino-4,4 -bis(dimethylamino)-benzophenone with the dianhydrides of aromatic tetracarboxylic acids (pyromellitic, benzophenone-3,3, 4,4 -tetracarboxylic and diphenyloxide-3,3, 4,4 -tetracarboxylic acids) were carried out using a two-stage process including room temperature reaction of starting monomers in NMP, formation of PCA and subsequent cyclodehydration of the... 

Imidisation of PCA based on 4,4 -di-(/7-aminophenoxy)-benzophenone was accompanied by the precipitation of the polymers from the reaction solutions, which is partially due to crystallinity in the polyimides formed. This appears to hinder the solubility of the polymers in amide and phenolic solvents. Polyimides based on l,l-dichloro-2,2-di-(/7-aminophenoxyphenyl)-ethylene are more soluble. The polymer formed from this diamine and the dianhydride of benzophenone-3,3 -4,4 -tetracarboxylic acid is soluble in a TCE/phenol (3 1) mixture. 

Polyimides based on l-amino-3-phenoxy-5-(4-aminophenoxy)-benzene and snch dianhydrides as dianhydride of diphenyloxide-3,3 4,4 -tetracarboxylic acid, dianhydride A and dianhydride 6F are soluble in NMP, dimethylformamide (DMF), w-cresol, THF and chloroform. The polyimide based on benzophenone-3,3, 4,4 -tetracarboxylic acid dianhydride is partially soluble in w-cresol and NMP it is insoluble in chloroform, THF and DMF. Polypyromellitimide is insoluble in all the solvents tested. 

Polyimides based on 3,5-diaminodiphenylsulfide demonstrate that solubility in organic solvents strongly depends on the nature of the dianhydride used polymers based on dianhydride 6F and dianhydride A are soluble in NMP, chloroform and acetone polyimides based on diphenyloxide-3,3, 4,4 -tetracarboxylic and benzophenone-3,3, 4,4 -tetracarboxylic acid dianhydrides are soluble in NMP only. Polyimides demonstrate high aired NMP (0.79-1.20 dl/g) and moderate (210-250 °C) Tg values combined with high (400-460 °C) T egr-... 

P, pyromellitic dianhydride B, 3,3, 4,4 -benzophenone tetracarboxylic dianhydride 3,5-DAB, 3,5-diaminoben benzophenone 4-MPD, 4-methoxy-m-phenylene diamine 4,4 -DDE, 4,4 -diaminodiphenyl ether 4,4 -DDM, -h The figure in parenthesis is the number of water molecules estimated to be associated with iho corresponding polar gr... 

Benzoin derivatives and benzophenone derivatives were commercial products of the highest purity grade. They are 2,2 - dime-thoxy-2-phenyl acetophenone (DMPA), benzophenone (BP), 4-benzoyl-benzoic acid (BBA), 3,3, 4,4 -benzophenone and tetracarboxylic dianhydride (BTCD). 

Fully imidized soluble polyimides have ben prepared using monomers derived from diphenylindane and aromatic dianhydrides. Technical polymers (XU218, for instance), prepared from 1,1,3-trimethyl-diaminophenylindane and benzophenone-tetracarboxylic acid dianhydride, have been marketed over the last decade. Despite the partially aliphatic nature of polyimides containing the indane group, they show considerable retention of the thermal stability, with Tg values over 300 °C [107-110]. 

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