Complete recycling and valorization of waste textiles for value-added transparent films via an ionic liquid

Waste polyester-cotton blended textiles have huge production and most of them are incinerated and landfilled, leading to seriously environmental pollution and significant waste of natural resources. Hence, recycling these textile wastes to other value-added products in a sustainable and economical way is meaningful and urgent. In order to completely utilize and valorize polyester-cotton blended textiles, transparent regenerated cellulose films and high-purity recovered polyethylene terephthalate (PET) film were successfully prepared via ionic liquid 1allyl-3-methylimidazolium chloride (AmimCl). It is indicated that cotton fibers in waste polyester-cotton blended fabrics can be fully dissolved in AmimCl, resulting in efficient separation of polyester and cotton. The transparent cellulose films can be achieved after coagulating and drying processes. Moreover, the changes in morphology and crystalline structure of cellulose films regenerated in different coagulation bath were also investigated in detail, in which cellulose films with dense structure regenerated from water coagulation bath exhibited good mechanical properties and tensile strength was as high as 35 MPa, much higher than that of polyethylene (PE, 9 MPa) self-sealing bag membrane commonly used in laboratory, showing great potential application in packaging and wrapping fields. Meanwhile, the high purity PET residue was also reused as raw material to fabricate transparent and flexible PET film by melt pressing, whose tensile strength can reach 36 MPa. Consequently, a facile and eco-friendly process of recycling and reusing polyester-cotton blended textiles was developed and the high-valued utilization of waste polyester-cotton blended textiles can also be realized.

Automated summary

By using the ionic liquid AmimCl, transparent regenerated cellulose films and high-purity recovered PET films were successfully prepared, allowing for efficient separation of polyester and cotton and showing great potential in the packaging and wrapping fields.