Synthesis of amphiphilic poly(cyclooctene)-graft-poly(ethylene glycol) copolymers via ROMP and its surface properties

Macromonomer cyclooctene-poly(ethylene glycol) (cyclooctene-PEG) was first synthesized before being copolymerized with cyclooctene by ring opening metathesis polymerization (ROMP) to obtain an amphiphilic graft copolymer (poly(cyclooctene)-g-PEG) with polycyclooctene as the hydrophobic trunk chain and PEG as hydrophilic side chains. The structure of poly(cyclooctene)-g-PEG copolymer was characterized by FTIR and 1H-NMR. The surface properties of poly(cyclooctene)-g-PEG film were evaluated through water contact angle and X-ray photoelectron spectroscopy (XPS). Water contact angle decreased from 87.7° to 65.8° along with increasing the content of PEG. Protein adsorption results showed that poly(cyclooctene)-g-PEG copolymers had significant effect on preventing bovine serum albumin (BSA) from absorbing onto the polymer surface.