The Cover Feature shows a new approach to cyclic polylactide in the bulk ring‐opening polymerization (ROP) of l‐lactide by using ZIF‐8 as a heterogeneous catalyst. The ZIF‐8 catalyst assembled by spray‐drying technique displays high efficiency and good recyclability for this ROP reaction. The active acid and basic sites in ZIF‐8 are supposed to cooperatively catalyze the ROP reaction, particularly forming cyclic polylactide with high molecular weight. More information can be found in the Communication by Luo et al. on page 4135 in Issue 21, 2017 (DOI: 10.1002/cssc.201701438).

中文翻译：

---

封面功能：沸石咪唑骨架ZIF-8催化剂将l-丙交酯开环聚合为环状聚（丙交酯）（ChemSusChem 21/2017）

封面功能展示了一种新的方法，通过使用ZIF-8作为非均相催化剂，在l-丙交酯的本体开环聚合（ROP）中制备环状聚丙交酯。通过喷雾干燥技术组装的ZIF-8催化剂对该ROP反应显示出高效率和良好的可回收性。ZIF-8中的活性酸和碱性位点可以协同催化ROP反应，特别是形成高分子量的环状聚丙交酯。有关更多信息，请参见Luo等的《通讯》。就在问题21，2017年4135页（：10.1002 / cssc.201701438 DOI）。