Imide-type polymer

Most of the imide type polymers have rather good thermoresistance. For example LaRC-l-TPI starts decomposing at about 510 C. Pyrolysis products of these polymers generate various fragment molecules related to the polymer structure. Several results reported in literature regarding thermal decomposition of some polymers from this class are indicated in Table 13.4.2. 

Development of Imide-Type Polymer Fibers Containing Metal Nanoparticles... 

Hulubei C, Hamciuc E, Bruma M. New imide type polymers based on epiclon. Rev. Roum. Chim. 2007 52(8-9) 891-898. 

This group is very thermally stable. Aliphatic im-ides are possible, but the thermal stability is reduced, and thermal stability is one of the main reasons to use an imide-type polymer. 

TSTR-type polymers are actually copolymers of TSTR and other heat-resistant polymers of aromatic or heterocyclic ring structures such as aromatic imides, phenylquin-oxalines, etc. ... 

It is found that simple salts, such as LiCl, do not provide high conductivity. In general, the bulkier the anion, the higher is the conductivity. For example, Armand (1994) synthesised lithium bis(trifluoromethylsulphonyl)imide, LiN(CF3S02)2, and observed high conductivity when dissolved in PEO-type polymer electrolytes. The high conductivity is the result of a more plasticised polymer. 

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. 

The addition to alkenes normally leads to unstable adducts that lose carbon dioxide under the reaction conditions. The intramolecular cycloaddition of the sydnone (30) takes place at room temperature, however (Equation (5)) and the cycloadduct (31) has been characterized <86HCA927>. The unstable species formed by the loss of carbon dioxide are also azomethine ylides. It is therefore possible for a second 1,3-dipolar addition to take place, as illustrated in Scheme 6 for the reaction of 3-phenylsydnone with Al-phenylmaleimide <86TL317,92JA8414>. This 2 1 addition has been used as the basis of a synthesis of polyimides. Imides of the type (32) were used as the dipolarophiles and their reaction with 3-phenylsydnone gave linear polymers <87MM726>. 

New types of polymers containing imide groups were proposed recently with high photosensitivity [237, 238] of the order less than lpj. Photosensitivity of the polymers composed of a series of thiophenylenes moieties and imide groups [238] remarkably increased with the increase of crystallinity. The overlapped rr-orbitals perpendicular to the polymer chains lead to the more extended conjugated system. 

---