Synthesis of poly(sebacic anhydride): Effect of various catalysts 5 on structure and thermal properties
Abstract
The authors investigate the efficiency of various catalysts (22 types, based on oxides, carbonates, chlorides, organometallic compounds, N-he terocyclic carbine based com- pounds, cadmium acetate and molecular sieves) in the process of poly(sebacic acid) anhydride (PSA) synthesis. Their efficien- cy was studied utilizing methods th at characterize the molecular weight distribution (gel permeation chromatography, GPC), structure (Fourier transform infrared spectroscopy (FT-IR), nu- clear magnetic resonance (NMR), mass spectroscopy (MS)) and thermal properties (differential scanning calorimetry, (DSC), thermogravimetry (TGA)) of the final products.
Such structural characterization gave good insight into the resulting polymer structure. Findings reveal the cru cial role of catalyst selection in the resulting properties of PSA.
The maximum M w values reached were found at approximately 280 kg.mol-1 ,whichin the case of the calcium oxide catalyst was achieved after 60 min of reaction. TGA analyses showed a two-step thermal degrada- tion process for all samples.
No significant effect of the catalyst used was observed on polyanhyd ride thermal stability. Howev- er, it was proven that such catalysts do significantly influence the crystallinity of the resulting polyanhydrides.