Polyesterimides

PHTHALIC ACID AND OTHERBENZENEPOLYCARBOXYLIC ACIDS] (Vol 18) -polyesterimide from fiEAT-RESISTANTPOLYTffiRS] (Vol 12)... 

Alkylated and alkenated toluenediamines are used as antioxidants (qv) in oils and elastomers (10,53,63—65), as chemical intermediates for polyamides, polyimides, and polyesterimides (53,1) and as epoxy curatives (53,58,66) (see Epoxy resins). 

This includes inorganic materials such as glass fibre and mica impregnated or glued together with epoxy, polyesterimide, polyurethane or other resins having superior thermal stability. 

PI, polyimide, can be used short-time up to 500 °C. Related to PI are poly-etherimides, polyesterimides en polyamidimides. 

The physical properties of systems having imide groups incorporated with epoxy resin was not seen until much later. Researchers in Korea performed microscopic analysis of commercially available polyetherimide (ULTEM1000) modified epoxy resins [40]. In their work, electron micrographs of the systems showed a two phase system even though their systems were limited to polyimide contents of less then 10 wt%. Compatibilizing polyesterimides with polyetherimides in order to fabricate in situ epoxy composites was addressed by Seo et al. [41]. 

Fig. 3. Changes of viscosity t, elastic modulus G and loss modulus G" in the proc of thermal treatment of polyesterimide [18]. T = 350 °C...

Wholly aromatic polyesterimides which exhibit nematic phases were first described in patents to DuPont [6] and Idemsitsu Chem [7].These were essentially copolyesters of three monomers, one of which was a dicarboxlic acid imide. 

Since 1991 Kricheldorf has published many other articles on liquid crystal polyesterimides. These include two series of thermotropic copoly(esterimides) derived from N-(3 -hydroxyphenyl)trimellitimide and 4-hydroxybenzoic acid or 6-hydroxy-2-naphthoic acid, in which the critical compositions for obtaining mesophases were discovered by varying monomer levels [34]. A series of homopoly(esterimide)s were synthesised from N-(4-carboxyphenyl)trimelliti-mide and various diacetylated linked diphenols. When the diphenol contained an ether or carbonyl linking group, mobile nematic phases were observed. Various naphthalene diols were also employed instead of the diphenol, but only the 2,7-dihydroxy naphthalene produced a nematic phase [35]. 

The nature of ring substituents can play an important part in determining mesogenicity. Nematic phases are often observed with single substituents, e.g methyl, phenyl, chloro-, but lead to isotropic polymers when the number of substituents on the ring is increased to two or more. Kricheldorf [52] gives examples of polyesters and polyesterimides which show this effect. 

Table 9. Determination of critical MI values in polyesterimides. The following table applies to the two varying polyesterimide compositions (25) (1) Copolyesterimide of m-amino phenol trimellitimide (A) and 2,6 hydroxynaphthoic acid (B) (2) copolyesterimide of m-amino phenol trimellitimide (A) and 1,4 hydroxybenzoic acid (B)...

Direct evidence for these assignments was obtained from critical composition values obtained for two series of polyesterimides synthesised by Krichel-dorf and co-workers [76] (Table 9). In both series, a preformed unit comprising the trimellitimide of raefa-aminophenol is copolymerised with either 2-hydroxy naphthalene 6-carboxylic acid or 4-hydroxybenzoic acid. In both series, the critical value at which a mesogenic phase is first observed is 10.0, at a 1 1 composition. An isotropic phase was observed at 9.6 and below. Hence the critical value must lie between the limits of 9.6 and 10. 

Isoweld . [Schenectady] Solderable polyesterimides for wire enamels. 

Thermo-oxidative Degradation of Polyesterimides, Polyamidoimides, Aliphatic-Aromatic Polyamides [7, 21, 40-43]... 

Dobbelstein A, Hille HD, Holfort H. Tereph-thalic trimellitic polyesterimides for electric insulation. DE patent 1937311, assigned to Herberts, Dr. Kurt, und Co. 1971. 

Chemical Structure of a Polyesterimide Made from Trimellitic acid anhydride,... 

The solubility parameter values of the polyesterimide (10.76 [182]), the novolae (10.7), and the resole (11.1), imply that these polymers should be thermodynamieally miseible beeause the differenee of these parameters between the polyesterimide and a phenolie resin is a small number. The theoretieally predieted miseibility of polyesterimide with novolae or resole appears to be bom out experimentally sinee differential thermal analysis shows a single glass transition temperature for all the blends, and seanning eleetron... 

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