Polyurethane(PU) was synthesized from polytetramethylene glycol(PTMG), 4,4'-diphenylmethane diisocyanate(MDI), and ethylene diamine(ED) as a chain extender. To modify the surface of newly synthesized polyurethan films, PU films were treated with oxygen plasma treatment at different conditions. The maximum concentration of peroxide generated on the PU film by oxygen plasma treatment was about 2.4n㏖/㎝² as determined by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method. Acrylic acid was grafted on the PU film using peroxy radicals generated as initiating sites. The concentration of acrylic acid grafted on the surface of PU film was about 1.7μ㏖/㎝² when the amount of acrylic acid grafted was calculated by the rhodamine interaction method. The chemical properties of the surface-modified PU films were characterized by the Attenuated Total Reflection Infrared (ATR-IR) and Electron Spectroscopy for Chemical Analysis (ESCA). The water contact angles of the surface-modified PU films were examined using a contact angle goniometer and the results showed that the hydrophilicity of PU films were highly improved by oxygen plasma treatment and acrylic acid grafting.

Polytetramethylene glycol(PTMG), 4,4'-diphenylmethane diisocyanate(MDI) 그리고 쇄연장제로서 ethylene diamine(EI)을 사용하여 폴리우레탄(PU)을 합성하였다. 합성폴리우레탄 필름의 표면개질을 하기 위해 압력과 조사시간을 달리하여 산소 플라즈마 처리를 하였다. 1,1-Diphenyl-2-picrylhydrazyl(DPPH)를 사용하여 표면에 생성된 peroxide를 정량한 결과, 필름표면에는 최대 2.4nmol/cm²의 peroxide가 생성하였다. 필름표면에 생성된 radical을 이용하여 아크릴산을 그라프트 중합하였으며, 단위 면적당 아크릴산의 농도는 rhodamine interaction 법으로 측정했을 때 최대 1.7μmol이었다. 표면 처리한 폴리우레탄 필름표면의 화학적 조성은 Attenuated Total Reflection Infrared(ATR-IR)과 Electron Spectroscopy for Chemical Analysis(ESCA)를 이용하여 검토하였다. Contact angle 법을 이용하여 표면개질 폴리우레탄 필름의 적심성을 조사한 결과, 산소 플라즈마 처리한 PU-Plasma>아크릴산을 그라프트 한 PU-COOH>미처리 PU의 순으로 친수성이 증가함을 알 수 있었다.

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