Surface coating and characteristics of ester-free poly(trimethylene carbonate) bearing an aromatic urea moiety for biomaterials use†
As a contribution to future developments in biomaterials surface science, this study investigated the polymer properties and surface coating performance of urea-functionalized ester-free poly(trimethylene carbonate), 1-(2-mercaptoethyl)urea poly(trimethylene carbonate) (PTMCM-SU). An aromatic PTMC derivative bearing a vinyl moiety (PTMCM-VB) as a precursor was modified to PTMCM-SU via UV irradiation. In polymer design, hydrogen interaction may be induced in the PTMCM-SU by the presence of 1-(2-mercaptoethyl)urea (SU). Here, the glass transition temperature (Tg) of PTMCM-SU was increased to −2 °C compared to that of non-functionalized PTMC at −29 °C. The wettability of the polymer coatings on glass, stainless steel, and polyethylene (PE) was also studied. PTMC and PTMCM-VB had similar hydrophobic surfaces but the PTMCM-SU surface was hydrophilic. Interestingly, the protein adsorption on PTMCM-SU showed a higher affinity to the coated materials, thus enhancing their bioactivity. We demonstrated that, by modifying PTMC with a urea pendant, we could tune the polymer functionality and promote biological responsiveness for its potential use as a coating surface for biomaterials.