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Poly(ε-caprolactone) has become an important biocompatible and biodegradable polymer. Indeed, due to its multiple biomedical applications, the synthesis of polycaprolactone has received increased attention in the past few decades. Moreover, microwave irradiation is a very clean modern technique widely used for green chemistry. Here, several polymers were synthesized by microwave irradiation, without any solvent, using nontoxic, biologically acceptable lanthanide halides as initiators. Reaction times varied between 2 and 90 min. The molecular weights of the obtained polymer products were between 3,000 and 16,000 g/mol. After polymerization, the polycaprolactone polymers were functionalized by reaction with 2-hydroxyethyl methacrylate. Hydrolytic and enzymatic degradation of the synthesized polymers were compared and discussed.

Poly‐(ϵ‐caprolactone) is a biodegradable polymer, which can be used for both medical and environmental applications.Due to its multiple applications the synthesis of such a polymer has been attracting an increasing attention in the past few decades.In our work, the polymers were synthesised by bulk polymerisation, using different lanthanide halides as initiators. The lanthanide derivatives are known as very active catalysts in the ring‐opening polymerisation of cyclic esters. Moreover, they are not toxic in comparison of catalysts, which are usually used for this synthesis.In this paper, the influence of the lanthanides on both the hydrolytic and enzymatic degradation of the PCL obtained by ring‐opening polymerization of ϵ‐caprolactone with different lanthanide‐based catalysts such as: lanthane chloride (LaCl3), ytterbium chloride (YbCl3) and samarium chloride (SmCl3) was assessed.Samarium seems to slightly accelerate the hydrolytic degradation of the polymer and to slow down or inhibit its enzymatic degradation, mainly when the molecular weight of the polymer is high. The behaviour of PCL containing another lanthanide like lanthane is dependent on the nature of the metallic ion. Complete degradation, by the Lipase PS from Pseudomonas cepacia, is achieved only with Ytterbium.

BACKGROUND: Amphiphilic block and graft copolymers constitute a very interesting class of polymers with potential for biomedical applications, due to their special characteristics, which derive from the combination of properties of hydrophilic and hydrophobic moieties. In this work, the synthesis and biodegradation of poly(2hydroxyethyl methacrylate)-graft-poly(L-lactide) are studied. RESULTS:The graft copolymers were synthesized using the macromonomer technique. In a first step, methacryloyl-terminated poly(L-lactide) macromonomers were synthesized in a wide molecular weight range using different catalysts. Subsequently, these macromonomers were copolymerized with 2-hydroxyethyl methacrylate in order to obtain a graft copolymer. These new materials resemble hydrogel scaffolds with a biodegradable component. The biodegradation was studied in hydrolytic and enzymatic environments. The influence of different parameters (molecular weight, crystallinity, ratio between hydrophilic and hydrophobic components) on the degradation rate was investigated.CONCLUSION: Based on this study it will be possible to tailor the release properties of biodegradable materials. In addition, the materials will show good biocompatibility due to the hydrophilic poly(2-hydroxyethyl methacrylate) hydrogel scaffold. This kind of material has potential for many applications, like controlled drug-delivery systems or biodegradable implants.