Under the threat of environmental pollution caused by waste plastics, environmentally friendly and biodegradable materials with superior performance have attracted worldwide public attention. Herein, by combining solid-state shear milling (S3M) and biaxial stretching technologies, high-performance and environmentally friendly poly­(vinyl alcohol) (PVA)/kaolin barrier films used for packaging were fabricated. The highly effective S3M technology simultaneously achieved the in situ exfoliation and superior dispersion of layered kaolin in the PVA matrix at ambient temperature. These kaolin nanoflakes featured a thickness of ∼3 nm and a width of ∼70 nm, thus effectively blocking the movement of PVA molecular chains and leading to the increase of glass transition temperature (T g) as well as the initial degradation temperature of the PVA matrix. By further synchronously biaxial stretching, benefiting from the well-dispersed kaolin and the oriented PVA molecular chains, the obtained anisotropic composite film with 5 wt % kaolin exhibited extremely high yield strength (138.7 MPa), tensile strength (146.4 MPa), and Young’s modulus (5.5 GPa), as well as excellent ultraviolet (UV) and oxygen barrier properties. This work not only highlights a novel strategy for achieving synchronous exfoliation and dispersion of layered clay minerals in a polymer matrix but also facilitates the green development of high-performance polymer-based films used for packaging.

With the rapid development of modern intelligent industry and the Internet of Things, the demand for multifunctional electromagnetic interference (EMI) shielding material has increased for complicated application scenes. Herein, derived from a hazardous waste, i.e., leather solid waste (LSW), a silver/LSW/poly­(vinyl alcohol) (PVA) membrane has been prepared via resourceful combination of solids state shear milling (S3 M) and electroless plating technology. The debundled leather fibers prepared by S3 M can act as template for silver electroless plating and thus conductive Ag/LSW fibers with high aspect ratio and electrically conductive were achieved. Moreover, Ag/LSW fibers were integrated into film and sealed with PVA to form the Ag/LSW/PVA membrane. Owing to the high conductivity and mechanical performance of PVA, the Ag/LSW/PVA membrane (1.2 mm) exhibited EMI shielding (62 dB), mechanical robustness (tensile strength reached to 89.7 MPa), and Joule heating capability (56 s to 101.3 °C). Impressively, the multifunctional membrane exhibits great potential in future smart oil stations, where under the premise of satisfying high-efficiency electromagnetic shielding, the Ag/LSW/PVA membrane can effectively absorb heavy crude oil through the Joule heating and porous structure and achieve double protection for electronic devices.

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With the intention to abate the pollution arising from the improper handling of petroleum-based plastic, green composites consisting of biodegradable plastics and biomass wastes have received widespread attention. However, the balance between mechanical performance and biodegradability still has not been reconciled and evaluated. Herein, a concept for water-soluble poly(vinyl alcohol) (PVA)/biomass waste composite materials is proposed. Instead of degrading to small molecules, the PVA matrix can dissolve in water within the soil. Moreover, after PVA was composited with waste cottonseed shell (CTS) using solid-state shearing milling (S 3 M) technology, considerable mechanical and thermal performance was achieved, with the maximum tensile strength and degradation temperature of the PVA/CTS composites reaching 10.3 MPa and ∼250 °C, respectively. Moreover, the soil burial test demonstrated that even if PVA cannot degraded in environment within a short term, its water-soluble nature ensures its environmental friendliness, as the PVA matrix can dissolve in soil in 10 days without imposing any adverse effects on either plants (wheat) or animals (earthworm). This work not only describes the preparation a series of ecofriendly PVA/biomass composites but also provides new insight into the environmental friendliness of PVA-based materials.

Antistatic packaging film plays an important role in protecting sensitive electronic components from the damage of electrostatic discharge (ESD) during transportation and application. Considering the antistatic property and environmental friendliness of polyvinyl alcohol (PVA), PVA was chosen as matrix to prepare PVA/carbon fiber (CF) composite film via melt casting and asynchronous biaxial stretching. The addition of CF made more perfect conductive pathway formed in system, thus improving the electric property of the composite precursor sheet. And the subsequent biaxial stretching further promoted the cross arrangement of CF as well as the orientation of PVA molecular chains, so endowed the stretched composite film with excellent mechanical, antistatic and water‐resistant properties. When CF content was 5 wt% and the stretching ratio was 3.0 × 3.0, the tensile strength, volume resistivity and water contact angle of the composite film reached 69.4 MPa, 1.07 × 105 Ω·cm, and 74.7° respectively, which met the requirements of electrostatic dissipation packaging. This work highlights the structural evolution of PVA/CF composites under biaxial stretching and spurs the devising of antistatic packaging materials.