In order to prepare a A-B-A triblock copolymer having biomedical properties, polyurethane was synthesized with ester-type polyol, 4,4 -diphenylmethane diisocyanate and diamine. The amine groups were introduced into these terminal positions of the polyurethane molecules by the addition of ethylenediamine. Then, the triblock copolymers were synthesized from amino-terminated polyurethane as B block and N-carboxyanhydride of γ-methyl-L-glutamate as A block. To evaluate the blood compatibility, the microsphere column method was used, and adhered platelets morphology was investigated by using scanning electron microscope. The results showed that the blood compatibility of triblock copolymers were superior to that of homopolymers. Among the triblock copolymers, the blood compatibility of I-30 and Ⅱ-30 including 30 wt% polypeptide was superior to that of others. Also the type I (polyol Mw=1000) was slightly better than the type Ⅱ (polyol Mw=2000) for the property.

본 연구에서는 폴리우레탄과 생체단백질의 구성성분인 y-methyl-L-glutamate을 블록공중합하여 A-B-A triblock copotymer를 합성하였고 이에 대한 혈액적합성 및 물성을 검토하였다. 먼저 분자사슬말단에 아민기가 도입된 에스테르형 폴리우레탄을 합성하고, 이 합성물과 phosgene법으로 합성한 γ-methyl-L-glutamate L-carboxyanhydride(NCA)를 반응시켜 triblock copolymer를 합성하였다. 혈액실험은 microsphere column법으로 잔유혈소판수를 측정하였고 Lee-White 법으로 혈액응고시간을 측정하였으며 시차주사전자현미경으로 점착혈소판의 모폴로지를 관찰하였다. 실험결과, triblock copolymer의 혈액적합성은 폴리우레탄과 poly(γ-methyl-L-glutamate)(PMLG)각각의 homopolymer보다 우수하며 펩티드함량 30%인 I-30과 Ⅱ-30이 우수한 혈액적합성을 나타내고 있었다. 또한 polyol 단위분자량 1000으로 만든 type I이 2000으로 만든 type Ⅱ보다 다소 우수한 경향을 나타내고 있었다. 각 시료의 인장강도와 신장율 및 임계표면장력을 측정하였으며, 시차주사열량 분석(DSC) 및 wide-angle X-ray도 측정하였다.

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