Chemical vapour deposition of soluble poly(p-xylylene) copolymers with tuneable properties†
Chemical vapour deposition (CVD) is a technique widely applied for the synthesis of thin and highly conformal polymer coatings. The copolymerization of poly(1,4-xylylene)s (PPX), with 2-hydroxyethyl methacrylate (HEMA) via CVD revives a hardly investigated field of PPX chemistry. The use of alkyl substituted [2.2]paracyclophanes leads to soluble PPX-copolymers. Proof of copolymerization was obtained by correlation of both monomer units in 1H,13C-HMBC 2D-NMR spectra. Next, insoluble p(PX-N-co-HEMA) copolymers were synthesized in a modified commercially available SCS Labcoater. The availability of the hydroxy ester functionality of HEMA on the film surface was indirectly confirmed by the reduction of water contact angles down to 65°. Preliminary studies using human umbilical vein endothelial cells (HUVEC) indicate the cytocompatibility of as deposited p(PX-N-co-HEMA) films.