Poly (glycerol adipate) (PGA) can be produced from divinyl adipate and unprotected glycerol by an
enzymatic route to generate a polymer with relatively low molar mass (12 kDa). PGA bears a pendant
hydroxyl group which imparts a hydrophilic character to this water insoluble polymer. We have
examined the effect of synthesis temperature on polymer characteristics through various techniques
including FT-IR, 1H and 13C NMR, surface and thermal analysis, both to expand the data already present in
the literature about this material and to understand better its properties for potential pharmaceutical
applications. The use of a lipase (Novozym 435) as a catalyst suppresses cross-linking at the pendant
glyceryl hydroxyl through steric hindrance at the active site, thus producing polymers with low degrees
of branching (5e30%), and removes the need for any pre- or post-polymerization protection/deprotection
reactions. Careful temperature control during synthesis can give polymers with reproducible
molecular weights and reduced amounts of polymer branching compared to synthesis at higher temperatures.
Due to the ability of the synthetic route to produce a range of structures, PGA generated by
enzymatic routes may emerge as a useful biodegradable polymer platform to engineer solid dispersions
or nanoparticles for healthcare applications.