Minami Yasunori, Inagaki Yuuki, Tsuyuki Tomoo, Sato Kazuhiko, Nakajima Yumiko
Interdisciplinary Research Center for Catalytic Chemistry (IRC3), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan.
PRESTO, Japan Science and Technology Agency (JST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan.
JACS Au. 2023 Aug 17;3(8):2323-2332. doi: 10.1021/jacsau.3c00357. eCollection 2023 Aug 28.
Super engineering plastics, high-performance thermoplastic resins, show high thermal stability and mechanical strength as well as chemical resistance. On the other hand, chemical recycling for these plastics has not been developed due to their stability. This study describes depolymerization of oxyphenylene super engineering plastics via carbon-oxygen main chain cleaving hydroxylation reaction with an alkali hydroxide nucleophile. This method is conducted with cesium hydroxide as a hydroxy source and calcium hydride as a dehydration agent in 1,3-dimethyl-2-imidazolidinone, which provides hydroxylated monomers effectively. In the case of polysulfone, both 4,4'-sulfonyldiphenol (bisphenol S) and 4,4'-(propane-2,2-diyl)diphenol (bisphenol A) were obtained in high yields. Other super engineering plastics such as polyethersulfone, polyphenylsulfone, and polyetheretherketone were also applicable to this depolymerization.
超级工程塑料，即高性能热塑性树脂，具有高热稳定性、机械强度以及耐化学性。另一方面，由于这些塑料的稳定性，尚未开发出针对它们的化学回收方法。本研究描述了通过与碱金属氢氧化物亲核试剂进行碳 - 氧主链裂解羟基化反应，对氧化苯撑超级工程塑料进行解聚。该方法以氢氧化铯作为羟基源，氢化钙作为脱水剂，在1,3 - 二甲基 - 2 - 咪唑啉酮中进行，可有效提供羟基化单体。以聚砜为例，可高产率地获得4,4'-磺酰基二苯酚（双酚S）和4,4'-(丙烷 - 2,2 - 二基)二苯酚（双酚A）。其他超级工程塑料，如聚醚砜、聚苯砜和聚醚醚酮，也适用于这种解聚反应。
