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采用溶剂热法和直接混合法合成了3种金属有机骨架材料(Zn-MOFs),研究了其在碳酸乙烯酯(EC)与丁二酸二甲酯(DMSu)耦合反应制聚丁二酸乙二醇酯(PES)和碳酸二甲酯(DMC)反应中的催化性能,并对工艺条件进行了考察.采用X射线粉末衍射法(XRD),扫描电子显微镜(SEM),傅里叶转化红外光谱法(FTIR)和原子发射光谱法(ICP-AES)对Zn-MOFs进行了表征,对聚合物PES进行了FTIR和核磁共振(~1HNMR和~(13)C-NMR)测试.结果表明,既具有MOF-5结构,又含有较多Zn O的纳米Zn-MOF-L催化活性最好.在Zn-MOF-L催化下,最优反应条件如下:预缩聚反应温度215℃,预缩聚反应时间4 h,缩聚反应温度220℃,缩聚压力小于300 Pa,n(EC)/n(DMSu)=2,催化剂用量为1 wt%.最优反应条件下,DMC的收率可达到65.08%,PES的特性黏数[η]可达到0.572 d L/g,数均相对分子质量M_n为2.1×104,相对分子质量分布PDI为2.21.
Three kinds of metal-organic framework materials (Zn-MOFs) were synthesized by solvothermal method and direct mixing method. The effects of coupling reaction of ethylene carbonate (EC) with dimethyl succinate Diol ester (PES) and dimethyl carbonate (DMC), and the process conditions were investigated.X-ray powder diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared Zn-MOFs were characterized by FTIR and ICP-AES. FTIR and 1H NMR spectra of the polymer PES were measured. The results showed that, The best catalytic activity of Zn-MOF-L with both MOF-5 and ZnO are as follows: The optimal reaction conditions are as follows: the pre-polycondensation reaction temperature is 215 ℃, the pre-polycondensation reaction Time was 4 h, the temperature of polycondensation reaction was 220 ℃, the polycondensation pressure was less than 300 Pa, n (EC) / n (DMSu) = 2 and the amount of catalyst was 1 wt%. Under optimum conditions, the yield of DMC reached 65.08% The intrinsic viscosity [η] of PES was 0.572 d L / g, the number average molecular weight M_n was 2.1 × 104, and the relative molecular mass distribution PDI was 2.21.