Synthesis and Characterization of a Novel Degradable Aliphatic Polyester that Contains Monomeric Lactate Sequences

Abstract

Summary: A novel degradable aliphatic polyester that contains monomeric lactate sequences is synthesized via melt‐polycondensation of ethylene glycol lactate diol (EGLD) with succinic anhydride without the use of catalyst. The structure of the EGLD precursor and the polyester are verified with FT‐IR and 1H NMR spectra. Gel permeation chromatography reveals that the weight‐average molecular weight of the polyester is 5.5 × 104 with a polydispersity index (PDI) of 1.7. Differential scanning calorimetry profiles reveal that the polyester is a semicrystalline polymer with a glass transition temperature of −12 °C and melting temperature of 101 °C. The weight loss percentage of the polyester after immersing for 208 d in active sludge is 2.7%, which suggests degradation has occurred.

Tailor‐made unsaturated poly(ester‐ amide) network that contains monomeric lactate sequences

“…Ethylene glycol lactate diol (EGLD) was prepared in our laboratory14 using lactic acid and ethylene glycol as starting materials. Maleic anhydride (MA; m.p.…”

“…The unsaturated dicarboxylic‐terminated oligoester (UDO) was prepared according to the literature 14, 17. In brief, a mixture of 20.6 g (0.154 mol) EGLD and 30.1 g (0.306 mol) MA was kept refluxing for 4 h. Then the mixture was allowed to react at the same temperature in vacuo for 24 h. The crude oligoester was purified by dissolving in chloroform and precipitating from methanol, and then drying under vacuum at ambient temperature to constant weight (29.4 g; yield: 58%).…”

“…Consequently, we are endeavoring to carry out suitable molecular design for preparing novel lactic acid‐based polymers to meet different requirements. A synthesis route for an aliphatic polyester containing a unitary lactate sequence has been developed in our laboratory 14. Amide groups have been incorporated into the backbone to prepare linear and porous three‐dimensional lactic acid‐based poly(ester‐amide)s that contain unitary lactate sequences 15, 16.…”

Synthesis and characterization of a novel poly(ester‐urethane) containing short lactate sequences and PEG moieties

“…Chain linking of LA-based hydroxyl-terminated prepolymer with diisocyanate is proven to be an efficient way to produce LPEU 30 and has been applied recently. 33 But the hydrophilicity of structure units on the chain is poor. [18][19][20][21] In viewing of this, we think LA-based polymers containing short lactate sequences probably exhibit some characteristic.…”

“…Accordingly, we have synthesized a LPEU which is composed of monomeric LA and ethylene oxide units. 33 But the hydrophilicity of structure units on the chain is poor. Therefore, the obtained polymer is hydrophobic enough and its degradation rate is low.…”