Über polyamide aus heterocyclischen dicarbonsäuren

Abstract

ZUSAMMENFASSUNG:Aus 21 heterocyclischen Dicarbonsauren wurden lineare Polyamide hergestellt. Kondensationen durch Schmelzen von Hexamethylendiammoniumsalzen waren ungiinstig, da die Produkte decarboxylierten, wahrend Kondensationen iiber Ester etwas bessere Resultate gaben. Einige Salze lieBen sich iiberhaupt nicht kondensieren. Mit 7 heterocyclischen Dicarbonsaurechloriden und verschiedenen Diaminen wurdenGrenzflachenpolykondensationen durchgefiihrt, doch waren auch diese Polyamide in geschmolzenem Zustand nicht bestandig.Molekulargewichtsbestimmungen zeigten, dal) der Polykondensationsgrad nie iiber 30 lag.Vergleichsweise wurden Grenzfllchenkondensate aus aromatischen Dicarbonsauren oder Diaminen hergestellt. Es traten bei den. heterocyclischen Derivaten keine grundsatzlich neuen Eigenschaften a d . Schmelzpunkte oder Loslichkeiten sind wegen des niederen Kondensationsgrades nicht eindeutig auf den Einflul) des Heterorings zuriickzufiihreh.Es wird die Darstellung von zwei neuen Thiophendicarbonsauren (Thiophen-2,5-diessigsaure und -2,5-diacrylsaure) heschrieben. SUMMARY:Linear polyamides were prepared from 21 heterocyclic dicarboxylic acids. The preparation of polyamides by heating hexamethylendiammonium salts of dicarboxylic acids gave no satisfactory results because of strong decarboxylation. 60me salts could not be polycondensated at all. Better results were obtained by using esters of the corresponding acids.7 heterocyclic dicarboxylic acid chlorides were used for interfacial polycondensation with several diamines. These products, too, proved to be unstable in molten state.The degree of polycondensation was never above 30.Aromatic dicarboxylic acid chlorides or diamines were used in interfacial polycondensation. It was shown, that heterocyclic polyamides did not have fundamentally new properties.The syntheses of two new thiophenedicarboxylic acids, i.e. thiophen-%,5-diacetic acid and -2,5-diacrylic acid are described. l) Teil der Dissertation A. KRIEGER, Diss. ETH Ziirich 1961.

Synthesis and properties of polyamides from 2,5‐furandicarboxylic acid

“…This procedure should allow even greater mobility to the chains than the “oven” method reported above; however, no crystallization was observed by DSC. This amorphous nature has been previously observed in several studies, whereas in other studies, similar polymers (or synthesized with different diamines) were found to be semi‐crystalline …”

“…This amorphous nature has been previously observed in several studies, 13,23 whereas in other studies, similar polymers (or synthesized with different diamines) were found to be semi-crystalline. 10,12,24 The fact that the PA 6-F synthesized was not able to crystallize may come from its very low molar mass. Indeed, with short polymer chains, the concentration of chain termini in the material becomes very important and these chain ends are a source of a great deal of free volume, acting as defaults in the crystalline structure and thus preventing the formation of crystals.…”

Biobased polyesters and other polymers from 2,5-furandicarboxylic acid: a tribute to furan excellency

“…All these attractive features have definitely motivated some studies about furanic polyamides through the years (see e.g. references 51,52,54,[148][149][150][151][152][153][154][155][156][157][158], including those dedicated to furanic -aliphatic and furanic -aromatic polyamides. Despite the enormous potential of this family of polymers, which are real biobased alternatives to existing petrochemical polyamides, recent literature dealing with FDCA is scarce, 51,52,54 with most published studies dating back from decades ago.…”

“…Despite the enormous potential of this family of polymers, which are real biobased alternatives to existing petrochemical polyamides, recent literature dealing with FDCA is scarce, 51,52,54 with most published studies dating back from decades ago. [148][149][150]152,153,[155][156][157][158][159][160] There are, however, noticeable recent achievements envisaging a fruitful future 161 which will be the focus of the present section. The most obvious furan based monomers that have been described for the preparation of polyamides are FDCA and the corresponding dimethyl ester and acid dichloride derivatives; although 2,5bis(aminomethyl)furan (BAMF), and hydroxymethyl-2furancarboxamide (HMFA) were additionally used for this purpose (however, out of scope of this review).…”

Synthesis of Some Polyamides from Bis(thiosemicarbazone)acenaphthenequinone

“…These commercial polyamides have been reinforced with various ceramic phases [12][13][14][15] . There are numerous references to polyamides from aliphatic diamines and aromatic diacids and a far lesser number to polyamides from aromatic diamines and aliphatic diacids [16][17][18][19][20][21][22][23][24] . Probably the reason that aliphatic-aromatic polyamides have been studied…”