Telechelic polylactones functionalized with trimethoxysilyl groups

Telechelic poly(ε-caprolactone)s or poly(d,l-lactide)s were prepared by SnOct2-initiated polymerization of ε-caprolactone (εCL) or d,l-lactide (d,l-LA) coinitiated with 1,4-butane diol or tetra(ethylene glycol). These telechelic polyesters were in situ functionalized with 3-isocyanatopropyl trimethoxysilane (IPTMS) by SnOct2-catalized addition of the OH-endgroups. Analogously, star-shaped polyesters were synthesized and functionalized using 1,1,1-trishydroxymethyl propane or pentaerythritol as coinitiators. All functionalized polymers were characterized by 1H NMR and MALDI-TOF mass spectra. In crosslinking experiments with oligo(ethylene-glycol)s the trimethoxysilyl groups proved to be 10-30-fold more reactive than triethoxysilyl end-capped polyesters.