To advance a strategy of polymer-to-polymer upcycling of waste polyolefin by dehydrogenation then functionalization, we report successful hydroesterification of polycyclooctene (PCOE), an analogue for partially unsaturated polyethylene. Here, we convert PCOE to a linear analog for poly(ethylene-co-ethyl acrylate) (EEA) across a range of ethyl acrylate incorporations (0 to 18 mol % of ethylene units). The ester incorporation was well controlled by reaction time, and the remaining C═C bonds were subsequently hydrogenated. The bulky ethyl acrylate groups did not incorporate into orthorhombic PE crystals, decreasing the crystallinity, crystallite size, and melting temperature with increasing functionalization. Additionally, hydroesterification tuned the dynamic mechanical properties, decreasing both the glass transition temperature and the storage modulus in the rubbery regime with greater functionalization. The linear EEA analogs reported here achieve remarkable extensibility (strain > 4000%) and high toughness, comparable to commercial random and branched EEA. Ultimately, we demonstrate successful conversion of an analogue to dehydrogenated PE to a linear EEA with favorable mechanical properties.

中文翻译：

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聚环辛烯的氢化酯化得到线性乙烯乙基丙烯酸酯共聚物，作为实现聚烯烃功能化的一个步骤


为了推进通过脱氢然后功能化对废聚烯烃进行聚合物-聚合物升级回收的策略，我们报道了聚环辛烯 （PCOE） 的成功氢化酯化，这是一种部分不饱和聚乙烯的类似物。在这里，我们将 PCOE 转换为聚丙烯酸乙酯掺入范围（乙烯单位的 0 至 18 mol %）的聚（乙烯-丙烯酸乙酯共聚乙酯）（EEA） 的线性类似物。反应时间很好地控制了酯的掺入，剩余的 C═C 键随后被氢化。大块的丙烯酸乙酯基团没有掺入斜方晶系 PE 晶体中，随着功能化的增加，结晶度、晶粒尺寸和熔融温度降低。此外，氢化酯化调节了动态机械性能，降低了橡胶状态下的玻璃化转变温度和储能模量，功能化程度更高。此处报道的线性 EEA 类似物具有显着的延展性（应变 > 4000%）和高韧性，可与商业随机和支链 EEA 相媲美。最终，我们证明了将类似物转化为脱氢 PE 的成功转化为具有良好机械性能的线性 EEA。