Green Solvent Processed Cellulose/Graphene Oxide Nanocomposite Films with Superior Mechanical, Thermal, and Ultraviolet Shielding Properties
Green Solvent Processed Cellulose/Graphene Oxide Nanocomposite Films with Superior Mechanical, Thermal, and Ultraviolet Shielding Properties
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DOI：
10.1021/acsami.9b19686
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发表时间：
2020-01-08
影响因子：
9.5
通讯作者：
Mukhopadhyay, Samrat
中科院分区：
文献类型：
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作者：
Ahmed, Abbas;Adak, Bapan;Mukhopadhyay, Samrat
本研究首次报道了一种绿色工艺来制备Lyocell纤维和氧化石墨烯（GO）基新型纤维素/氧化石墨烯纳米复合材料（CGN）柔性膜用于紫外线（UV）屏蔽应用。采用聚乙二醇（PEG）作为溶剂，通过溶液浇铸法制备CGN薄膜.为了改善GO片在纤维素基质中的分散性，通过用环氧氯丙烷（ECH）交联纤维素和GO片的含氧官能化基团，在纤维素和GO片的含氧官能化基团之间形成反应性界面。在纤维素基体中添加GO片导致了CGN纳米复合膜的结构和表面形貌的协同变化。在形态学研究中观察到GO片在CGN膜中的增强分散，这归因于通过氢键的充分的纤维素-GO相互作用，并导致机械和热性能的显著增强。与纯纤维素膜相比，具有2wt%GO负载的CGN膜（CGN 2）的拉伸强度和杨氏模量分别从55.6MPa和2.1GPa增加到89 MPa和4.3GPa。此外，CGN膜表现出显着的紫外线屏蔽能力，增加GO负载在纤维素基质。CGN 2膜（2wt%GO负载）在280至400 nm的波长范围内具有突出的吸光度，并且在UV-B和UV-A区域中显示出几乎完全屏蔽（类似于99%）UV射线。此外，CGN 2膜的紫外线防护因子比纯纤维素膜的紫外线防护因子提高了80倍以上。所得CGN纳米复合膜在紫外防护领域具有很高的应用潜力。
This study reports for the first time a green process to fabricate Lyocell fiber and graphene oxide (GO) based novel cellulose/graphene oxide nanocomposite (CGN) flexible films for ultraviolet (UV) shielding applications. A polyethelene glycol (PEG) mediated solvent system was utilized to make CGN films via solution casting route. To improve the dispersion of GO sheets in a cellulosic matrix, a reactive interface was formed in between cellulose and oxygenic functionalized groups of GO sheets via cross-linking them with epichlorohydrin (ECH). The addition of GO sheets in cellulose matrix leads to the synergistic changes, which were observed in the structure and surface morphology of CGN nanocomposite films. Enhanced dispersion of GO sheets in CGN films was observed in morphological investigations which is attributed to the adequate cellulose-GO interaction by hydrogen bonding and led to significant enhancement in the mechanical and thermal properties. The tensile strength and Young's modulus of CGN films with 2 wt % GO loading (CGN2) increased to 89 MPa and 4.3 GPa from 55.6 MPa and 2.1 GPa, respectively, as compared to the neat cellulosic film. Additionally, the CGN films exhibited remarkable UV shielding capability which increased with GO loading in a cellulose matrix. The CGN2 film (2 wt % GO loading) possessed outstanding absorbance in the wavelength range of 280 to 400 nm and showed almost complete shielding (similar to 99%) of UV rays in both the UV-B and the UV-A regions. Moreover, the ultraviolet protection factor of the CGN2 film demonstrated more than 80-fold increase compared to that of the neat cellulose film. The obtained CGN nanocomposite film has a high potential for applications in the field of UV protection.