The Back Cover picture shows our new zinc carboxyguanidine catalyst for the ring‐opening polymerization of lactide to polylactide (PLA), a biodegradable polyester. Lactide originates from maize, sugar beets, or sugar cane as renewable resources. PLA is well‐known but up to now industrially produced only by tin catalysts. Our catalyst represents a viable alternative for the melt polymerization (monitored by Raman spectroscopy) owing to its extraordinary robustness and activity. More details can be found in the Full Paper by Schäfer et al. (on page 3547 in Issue 18, 2017 DOI: 10.1002/cssc.201701237).

中文翻译：

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封面文章：丙交酯开环聚合的高活性N，O锌胍催化剂（ChemSusChem 18/2017）

封底图片显示了我们用于丙交酯到可生物降解的聚酯聚丙交酯（PLA）开环聚合的新型锌羧胍催化剂。丙交酯来源于玉米，甜菜或甘蔗，可再生资源。PLA是众所周知的，但到目前为止，仅通过锡催化剂在工业上生产。我们的催化剂具有非凡的耐用性和活性，是熔体聚合（通过拉曼光谱法监测）的可行替代品。更多细节可以在Schäfer等人的论文全文中找到。（在2017年第18期第3547页DOI：10.1002 / cssc.201701237）。