Browe Matthew A, Landers John, Tovar Trenton M, Mahle John J, Balboa Alex, Gordon Wesley O, Fukuto Masafumi, Karwacki Christopher J
DEVCOM Chemical Biological Center, 8198 Blackhawk Rd., Aberdeen Proving Ground, Maryland 21010, United States.
National Research Council, Washington, D.C. 20001, United States.
ACS Appl Mater Interfaces. 2021 Mar 3;13(8):10500-10512. doi: 10.1021/acsami.1c00397. Epub 2021 Feb 19.
A strategy is developed to enhance the barrier protection of polyethylene oxide (PEO)-metal-organic framework (MOF) composite films against chemical warfare agent simulants. To achieve enhanced protection, an impermeable high-aspect-ratio filler in the form of Laponite RD (LRD) clay platelets was incorporated into a composite PEO film containing MOF UiO-66-NH. The inclusion of the platelets aids in mitigating permeation of inert hydrocarbons (octane) and toxic chemicals (2-chloroethyl ethyl sulfide, 2-CEES) of dimensions/chemistry similar to prominent vesicant threats while still maintaining high water vapor transport rates (WVTR). By utilizing small-angle neutron scattering, small-angle X-ray scattering, and wide-angle X-ray scattering, the LRD platelet alignment of the films was determined, and the structure of the films was correlated with performance as a barrier material. Performance of the membranes against toxic chemical threats was assessed using permeation testing of octane and 2-CEES, a common simulant for the vesicant mustard gas, and breathability of the membranes was assessed using WVTR measurements. To assess their robustness, chemical exposure ( diffuse reflectance infrared Fourier transform spectroscopy) and mechanical (tensile strength) measurements were also performed. It was demonstrated that the barrier performance of the film upon inclusion of the LRD platelets exceeds that of other MOF-polymer composites found in the literature and that this approach establishes a new path for improving permselective materials for chemical protection applications.
开发了一种策略来增强聚环氧乙烷（PEO）-金属有机框架（MOF）复合膜对化学战剂模拟物的阻隔保护。为了实现增强保护，将锂皂石RD（LRD）粘土薄片形式的不可渗透高纵横比填料掺入含有MOF UiO-66-NH的复合PEO膜中。薄片的加入有助于减轻尺寸/化学性质与突出的糜烂性威胁相似的惰性烃（辛烷）和有毒化学品（2-氯乙基乙基硫醚，2-CEES）的渗透，同时仍保持高水蒸气透过率（WVTR）。通过利用小角中子散射、小角X射线散射和广角X射线散射，确定了薄膜中LRD薄片的排列，并将薄膜的结构与作为阻隔材料的性能相关联。使用辛烷和2-CEES（糜烂性芥子气的常见模拟物）的渗透测试评估了膜对有毒化学威胁的性能，并使用WVTR测量评估了膜的透气性。为了评估它们的坚固性，还进行了化学暴露（漫反射红外傅里叶变换光谱）和机械（拉伸强度）测量。结果表明，加入LRD薄片后薄膜的阻隔性能超过了文献中发现的其他MOF-聚合物复合材料，并且这种方法为改进用于化学防护应用的渗透选择性材料开辟了一条新途径。
