All-dry synthesis and coating of methacrylic acid copolymers for controlled release.

Initiated chemical vapor deposition (iCVD) is presented as an all-dry synthesis and coating method for applying methacrylic acid copolymers as pH-responsive controlled release layers. iCVD combines the strengths of liquid-phase chemical synthesis with a precision solvent-free chemical vapor deposition environment. Copolymers of methacrylic acid and ethyl acrylate were confirmed by a systematic shift in the carbonyl bond stretching mode with a shift in the comonomer ratio within the copolymer and by the ability to apply the Fineman-Ross copolymerization equation to describe copolymerization kinetics. Copolymers of methacrylic acid and ethylene dimethacrylate showed pH-dependent swelling behavior that was applied to the enteric release of fluorescein and ibuprofen.