Catalyst-Free Plasma-Assisted Copolymerization of Poly(ε-caprolactone)-poly(ethylene glycol) for Biomedical Applications.

Catalyst-free ring-opening polymerization (ROP) strategy was developed to overcome the disadvantage of incomplete and expensive removal of catalyst used during the multistep wet chemical processes. Nano-sized biocompatible and low molecular weight poly(ε-carolactone)-poly(ethylene glycol) (PCL-PEG) copolymer coatings were deposited via a single-step, low-pressure, pulsed-plasma polymerization process. Experiments were performed at different monomer feed ratio and effective plasma power. The coatings were analyzed by XPS, as well as MALDI ToF. Ellipsometric measurement showed deposition rates ranging from 1.3 to 3 nm/min, depending on the ratio of the PCL/PEG precursors introduced in the reactor. Our results have demonstrated that plasma copolymerized PCL-PEG coatings can be tailored in such a way to be cell adherent, convenient for biomedical implants such as artificial skin substrates, or cell repellent, which can be used as antibiofouling surfaces for urethral catheters, cardiac stents, and so on. The global objective of this study is to tailor the surface properties of PCL by copolymerizing it with PEG in the pulsed plasma environment to improve their applicability in tissue engineering and biomedical science.