Полимеризация олигомеров молочной кислоты в условиях микроволнового облучения

Abstract

First studied the effect of the power and time for the polymerization of lactic acid oligomers (OLA) in the presence of catalysts D,L-α-alanine (α-Ala), D,L-β-alanine (β-Ala), D, L-β-phenyl-α-alanine (β-Phe-α-Ala), aminoacetic acid (Gly) and toluenesulfonic acid (TSA). It is found that the catalytic activity is studied at amino acid 280 W power varies among: β-Phe-α-Ala> Gly> α-Ala> β-Ala. A more effective catalyst is tert-butyl alcohol (t-BS.) compared with benzyl alcohol (BzS). Polymerization of OLA in the presence of TSA at a noticeable rate occurs already at 130 watts. Adding an electron-donor molecules (water, DMSO, benzyl alcohol) to TSA results in lower molecular weight PLA. It is suggested that the presence of so-called "microwave effect" when OLA polymerization in the presence of alanine and TSA, i.e at the same temperature (215 ° C) and the time at different powers (280, 360 W) OLA polymerization proceeds at different rates.