Mechanochemische Synthesen durch Polykondensation mit Polyestern als Grundsubstanz. 1. Mechanochemische Polykondensation von polyäthylenterephthalat mit Äthylendiamin

Abstract

ZUSAMMENFASSUNG:Es wird erstmals untersucht und bestatigt, daB die Auslosung von Polykondensationsvorgangen auf mechanochemische Weise moglich ist, wobei als polymerer Trager das Polyathylenterephthalat und als Kondensationspartner Diamine (Athylen-und Hexamethylendiamin) sowie zweibasische Sauren (Adipinsaure) verwendet werden. Der EinfluB der Dauer der mechanischen Beanspmchung und des Mischungsverhaltnisses der Reaktionspartner auf den Umsatz wird diskutiert. Die Kondensationsprodukte werden durch chemische und spektroskopische Methoden sowie durch B e s t i m u n g von Loslichkeit und Schmelzpunkt gekennzeichnet.Die Existenz mechanochemischer Umsetzungen wird auch an anderen Systemen (Polyamiden/zweiwertigen Allcoholen) nachgewiesen. SUMMARY:The paper raises and solves for the first time the question of the initiation through mechanochemical means of some polycondensating processes, using as support the polyethyleneterephthalate and as condensating agents diamines (ethylene and hexamethylendiamine) and diacids (adipic acid). The infloence of the duration of the mechanical stress and the ratio of mix+% of the reactants upon the yield is discussed. The products obtained are characterized by chemical and spectral methods as well as by determining some properties (solubility, melting point).The validity of such a process is also verified by other systems (polyamides, dialcohols).

Mechanochemically Synthesized Polymers with Special Properties

“…The idea of this new type of synthesis has been suggested by a phenomenon noticed during the mechanochemical destruction of polyamides, when it has been found that besides the homolytical splitting of the macromolecular chain, some condensation reactions take place, implying the interaction of the polymer carboxy 1 and amino groups [proved by their drastic reduction concentration from the medium (Oprea et al, 1969)l. Some condensation achievement between the various functional groups belonging to the destruction fragements, has also suggested the possibility of its develoment between the functional groups of a polymer and those of a judiciously selected micromolecular compound.…”

Mechanochemical Reactions of Some Poly-Urethane Thermoplastic Elastomers. 6. Study of Molecular Mechanism of Deformation and Fracture

“…Starting from the idea that through mechanical destruction of the heterocatenary polymers, a great number of functional groups are being accumulated (at the supermolecular level implying an accumulation of such groups along the magistral crack), these may lead to reactions called "mechanochemical polycondensations" (Oprea et al, 1969;Simionescu et al, 1978). When the aromatic diamines are used, these react with the final hydroxylic groups of the polyurethane elastomer: as a consequence of the homolytical scission of main-chain valence bonds.…”