离子交换树脂催化环氧化低分子聚异丁烯的研究

以H2O_2(过氧化氢)/乙酸为反应试剂、IER(离子交换树脂)为催化剂,采用原位过酸法合成了环氧化LPIB(低相对分子质量聚异丁烯)。考察了反应温度、反应时间、原料配比及IER含量等对产物的双键转化率、环氧值和环氧基团收率等影响,并采用单因素试验法优选出LPIB环氧化的最佳工艺条件。研究结果表明:LPIB的末端双键易被环氧化,并伴有一定量的副反应;LPIB环氧化的最佳工艺条件为n(双键):n(乙酸):n(H_2O_2)=1:0.7:1.65、w(IER)=13.5%(相对于树脂质量而言)、反应温度70℃和反应时间12 h,此时产物的双键转化率为86.5%、环氧值为0.083 mol/100 g和环氧基团收率为79.2%;IER循环使用4次后,其催化效率基本不变。

Supported Ziegler-Natta catalysts from MgCl_(2)·nROH precursors and its catalytic behaviors for diene copolymerization

Heterogeneous TiCl4/MgCl_(2) type Ziegler-Natta(Z-N)catalysts with unique advantages like low cost,high activity,high stereoregularity and pretty particle morphology,contribute to more than 130 Mt polyolefin large-scale production.However,most researches related with heterogeneous Z-N catalysts focused onα-olefin polymerizations like ethylene,propylene,etc.