N-(4-乙烯基)苄基咪唑共聚物的合成及与钴卟啉络合物的氧结合性能

SYNTHESIS OF N-(4-VINYL)BENZYLIMIDAZOLE COPOLYMER AND OXYGEN-BINDING PROPERTIES OF ITS COMPLEX WITH COBALTPORPHYRIN

研究了N-(4-乙烯基)苄基咪唑单体及其与甲基丙烯酸辛酯共聚物(PBIOM)的合成与表征,以及咪唑基有机或聚合物配位体与钴卟啉(CoP)络合物的氧结合性能.合成的PBIOM重均分子量和咪唑基含量分别由GPC和元素分析方法测定,结果为3.4×105和57 mol%.PBIOM或苄基咪唑(BIm)中的咪唑基与CoP在溶液中配位,得到的CoP-PBIOM或CoP-BIm络合物具有快速、可逆的氧结合特性.相同氧气分压下CoP-BIm络合物在三氯甲烷溶液中的氧结合百分率略大于CoP-PBIOM络合物.CoP-PBIOM络合物固体膜的氧结合亲和力大于三氯甲烷溶液中的氧结合亲和力.60℃下CoP-PBIOM固体膜的氧结合半衰期为40.7 h,而CoP-BIm固体膜为8.8 h,表明聚合物配位体显著提高了CoP络合物的氧结合寿命.

N-（4-vinyl）benzylimidazole and its copolymer with octyl methacrylate （PBIOM） were synthesized and characterized, and oxygen-binding properties of cobahporphyrin （CoP） complexes with imdazole ligands were studied. The weight-average molecular weight and imidazole content of PBIOM were determined to be 3.4×10^5 and 57 mol % by GPC and elemental analysis, respectively. PBIOM or benzylimidazole （BIm） and CoP in chloroform solution were mixed to complex the imidazolyl residue of the ligands with the fifth coordination site of CoP under nitrogen atmosphere to get CoP complexes. CoP complex displayed a reversible change in the UV-visible absorption spectrum from the deoxy form to the oxygen-binding one with an isosbestic point, in response to the partial oxygen pressure of the atmosphere. The oxygen-binding equilibrium curves of CoP complexes obeyed a Langmuir isotherm, to give the oxygen-binding affinity P50 （ oxygen partial pressure at which half of the CoP binds with oxygen）. At the same partial oxygen pressure, the oxygen-binding ratio of CoP-BIm complex was a little larger than that of CoP- PBIOM complex.The oxygen-binding affinity of CoP-PBIOM complex in the solid membrane state was larger than that in chloroform solution.The half lifetime of CoP-PBIOM membrane at 60℃ was 40.7 h, while that of CoP-BIm membrane （poly（octyl methacrylate） as matrix） was 8.8 h, indicating that polymer ligand significantly prolonged the lifetime of CoP complex.