A straightforward approach based on thiol-ene click chemistry was used to prepare novel functional polyesters containing amino groups. First, a series of well-defined alkene-functional poly(3caprolactone)s were prepared by ring-opening polymerization of a-allyl-3-caprolactone with 3caprolactone in toluene and in bulk using tin 2-ethylhexanoate as catalyst. These functional polyesters were fully characterized by 1 H NMR, GPC, and MALDI-TOF MS. The resulting random copolyesters were obtained with a wide range of molar masses from 3000 to 50 000 g mol À1 and a good incorporation of the a-allyl-3-caprolactone monomer unit. Then, thiol-ene reaction of alkene-functional PCL with the 2-(Boc-amino)ethanethiol was used to prepare efficiently polyesters bearing protected amino groups without chain degradation. Finally, cationic and water-soluble polyesters bearing free amino groups were recovered by cleavage of the Boc protecting group. These aminated polyesters were characterized by 1 H NMR in deuterated water.

The present contribution reports on an original new class of acid-labile thermosensitive polyacrylamides, namely poly(tris(hydroxymethyl)acrylamidomethane-co-(5-acrylamido-5-hydroxymethyl-2,2-dimethyl-1,3-dioxane)) (P(THAM-co-pTHAM)), in which pTHAM only differed from THAM by an acetal group. The lower critical solution temperature (LCST) was controlled by varying the comonomer composition. Additionally, the properties of these new statistical copolymers were investigated and proved that such chemical structures were interesting for smart applications, notably for drug delivery due to the biocompatibility of low molecular weight PTHAM already demonstrated.