What have you come across so far in the litterature?

Starting from low- or medium MW polyesters, reactive chain extension with di- or polyfunctional chain extenders (epoxy, isocyanate, carbodiimide, oxazoline, carbonylbiscaprolactam,...) is another way to obtain high MW polyesters.

Hello there,

If you want to increase the molecular weight, i Believe your strategy for thermal cross linking will work. Just play with the reaction time also you can make the reaction under vacuum to remove water instead of touloene.

Thanks a lot for you answers and the time you have used for it.

To specify it further: I am targeting a linear high molecular weight homopolymer, using a bivalent aliphatic acid (heptanedioic acid) and a bifunctional semialiphatic alcohol as reactants.

@Tobias Abt: I think it is a good idea, but I would like a direct route and a homopolymer.

@Hesham Ismail:I used 24 h as reaction time, I think that is already quite high. Are you thinking about solid state polymerization, as it is described in Review of conventional and novel polymerization processes for polyesters (see paper attached).

@Guy Havet: I found e. g. the paper Preparation of high-molecular-weight aliphatic polycarbonates by condensation polymerization of diols and dimethyl carbonate (see paper attached). They are describing that it was quite difficult and many groups did not succeed in polymerizing high molecular weight aliphatic polycarbonate. They described that catalysts and drying of products had a crucial role. I wondered if there is also a paper for aliphatic polyesters, comprehensively describing a route to high molecular weight polymers with influencing factors. I found just isolated papers, describing cases which might not be transferable.

Article Review of conventional and novel polymerization processes fo...

Article Preparation of High-Molecular-Weight Aliphatic Polycarbonate...