Transparent cellulose/aramid nanofibers films with improved mechanical and ultraviolet shielding performance from waste cotton textiles by in-situ fabrication

Transparent Cellulose-Based Films Prepared from Used Disposable Paper Cups via an Ionic Liquid

“…The composition and crystal phases of polymer materials can be acquired by X-ray diffraction and the X-ray diffraction profiles of CPs, UPCs (the PE coating side), p-UPCs, PE film, Film-H, and Film-A were presented in Figure 5 a,b. As is shown in Figure 5 a, the raw material CPs, UPCs, and p-UPCs demonstrate well-defined peaks of cellulose phase I at 2θ = 15.1°, 16.8°, 22.8°, and 34.5°, corresponding to the (1–10), (110), (200) and (004) planes [ 12 , 16 , 31 ]. However, it is worth speaking that the UPCs (the PE coating side) and p-UPCs show some differences.…”

“…Nevertheless, UPCs (the PE coating side) exhibit a prominently different spectrum from those of the CPs and p-UCPs, and it is similar to the PE spectrum, meaning that the pretreatment can peel off most of the PE coating from cellulose paper board. In FTIR, some peaks such as the O-H stretching peak (3700 to 3200 cm −1 ) and C-H stretching peak (3000–2700 cm −1 ) are relatively sensitive to the cellulose structure change [ 12 , 15 , 16 ]. As is shown in Figure 5 c, the O-H stretching peak is located at 3290 cm −1 for the raw materials p-UPCs.…”

“…Meanwhile, the C-H stretching peak is located at 2894 cm −1 for p-UPCs, while it shifted to lower wavenumbers for Film-H (2881 cm −1 ) and Film-A (2885 cm −1 ), demonstrating a prominent red shift. It is worth noticing that the absorption band at 899 cm −1 and 1110 cm −1 are also usually used to analyze the changes of cellulose structure [ 16 , 28 ]. As is demonstrated in Figure 5 c, the absorption band at 899 cm −1 was weak in the spectrum of CPs and p-UPCs, but it enhances obviously for Film-H and Film-A.…”

“…However, the high-grade dissolving-grade pulps including wood pulps and cotton liner pulps are still the major source for producing cellulose-based materials, making the raw materials scarce and limiting the exploitation and application of cellulose-based products [ 11 , 12 , 13 ]. In contrast, the domestic wastes which are produced extensively every year can be a good candidate as raw materials [ 14 , 15 , 16 ]. Generally, the paper cups are composed of 95 wt% high-quality cellulose paper board and 5 wt% inner polyethylene (PE) coating [ 1 , 4 ].…”

“…Nevertheless, it has been proved that cellulose can be dissolved efficiently in ionic liquids (ILs) [ 25 , 26 , 27 ]. Moreover, converting low-cost cellulose-contained wastes into high-value cellulose-based materials has been investigated for many years in our previous studies [ 12 , 13 , 16 , 25 , 28 ]. In this work, by using UPCs as raw materials, transparent cellulose-based films with excellent mechanical and thermal properties were successfully prepared through a green solvent ionic liquid 1-allyl-3-methylimidazolium chloride (AmimCl).…”