CO₂-switchable hydrogels have been well documented during the past decade; however, the reversible response makes them unable to sequestrate CO₂ owing to the gas release and viscosity reduction under high temperatures, weakening their capacity to absorb CO₂. To address this issue, a series of copolymers based on grafting poly(dimethylaminopropyl methacrylamide) onto the backbone of sodium carboxymethyl cellulose (NaCMC) were prepared, characterized, and examined rheologically. In the semidilute entangled regime, the copolymer aqueous solutions can be gelled in the presence of CO₂, but they cannot revert to the solution phase after bubbling N₂ at 60 °C. With such irreversibility, 1 wt % aqueous solution of the copolymer with 24.88 mol % DMAPMAm can absorb CO₂ up to 12.1 mg·g^–1, whereas only 18.2% of the absorbed CO₂ is released after heating at 60 °C. This work paves a new way to develop irreversible hydrogels for CO₂ sequestration.

中文翻译：

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用于二氧化碳封存的纤维素基不可逆水凝胶


CO ₂ -可切换水凝胶在过去十年中已得到充分记录；然而，由于高温下气体释放和粘度降低，可逆反应使得它们无法封存CO ₂ ，削弱了它们吸收CO ₂ 的能力。为了解决这个问题，制备了一系列基于将聚（二甲基氨基丙基甲基丙烯酰胺）接枝到羧甲基纤维素钠（NaCMC）主链上的共聚物，并对其进行了表征和流变学检查。在半稀释缠结状态下，共聚物水溶液在 CO ₂ 存在下可以凝胶化，但在 60 °C 下鼓泡 N ₂ 后不能恢复到溶液相。由于具有这种不可逆性，1 wt% DMAPMAm 共聚物水溶液可吸收 CO ₂ 高达 12.1 mg·g ^–1 ，而仅吸收 18.2% 的 CO ₂ 。 b7>在60℃加热后释放。这项工作为开发用于 CO ₂ 封存的不可逆水凝胶开辟了一条新途径。