New polymers and polymeric systems based on epoxide oligomers and polyheteroarylenes. Review

Using PA11 and 12 as curing agents for epoxy networks: Influence of reactivity on miscibility and properties

“…5 Concerning the reactivity of amide functions toward an epoxy group, it seems, according to the literature, only possible at high temperature or with the use of a base catalyst. 10,11 The reaction mechanism between the amide functions and the oxirane group is not yet totally elucidated, but most studies consider that the first step involves the nucleophilic attack on the oxirane ring by the amide nitrogen and report the formation of ester groups. 10,12 These last groups are attributed to the isomerization of the hydroxylated molecule formed during the first step of reaction 12 or directly to the coordination of the epoxy group with amide followed by the break of the NHCO bond.…”

“…As shown by Figure 8, the conversion of epoxy groups seems quite complete after 180 min, whereas the concentration of ester groups still increases. Whereas homopolymerization of epoxy can explain the increase of the height of the ether peak, three mechanisms can be at the origin of the formation of ester groups: The first one implies the acid chains ends of Rilsan and the hydroxyl groups of the epoxy, the second one implies an isomerization of the molecule formed by the reaction between the epoxy and the amide as proposed by Komarova et al 10 and Iwakura and Izawa, 12 and the last one implies a reaction between amide groups and hydroxyl groups. To confirm the participation of amide groups in the formation of the reaction products, two systems were studied: The first one is composed of Orgasol PA and the DGEBA epoxy prepolymer, the content of PA being equal to 30 phr.…”

Trends in the development of polycondensation and condensation polymers

“…73,74 In particular, a combination of cardo polyheteroarylenes [e.g., poly(phenolphthalein terephthalate)] with epoxide oligomers upon moderate heating is a promising approach to their reprocessing into monolithic articles. The chemical reaction of an epoxy oligomer with a polyarylate, which occurs by the insertion (and opening) of the oxirane ring into the ester bond, results in the formation of a network structure, which manifests a set of specific properties.…”

Cardo polyheteroarylenes. Synthesis, properties, and characteristic features

“…4 ' io.i4,49-5i,8o-82 j n particular, a promising procedure for the conversion of cardo polyarylates, for example phenolphthalein polyterephthalate, into monolithic articles involves its combination with a reactive epoxide oligomer and subsequent moderate heating. The chemical interaction of the epoxyoligomer with the polyarylate (via a mechanism involving the 'insertion'of an oxirane ring in the ester bond 80 ) results in the formation of a network system having a specific set of properties and the region of mechanical usability of such compositions extends to more elevated temperatures compared with the traditional compositions based on oligoepoxides. 82 The part of the chemically reactive heat-resistant polymer in the composition with oligoepoxides which has not reacted serves as a filler.…”

“…49 -50 -88~91 It is also noteworthy that the introduction of even a small amount of a chromophore-containing monomer into mixed polyarylates derived from terephthalic acid and phenolphthalein greatly increases the resistance of the polymer to ultraviolet radiation. 80 Thus cardo polyarylates have enhanced thermal characteristics, satisfactory solubilities, and effective physicomechanical properties.…”