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It is crucial and significant to boost the utilization of renewable resources and exploitation of biodegradable materials alternative to petrochemical plastics. Waste paper, mainly composed of cellulose (82–95 wt%) and derived from the lignocellulose, is a type of abundant, renewable, and biodegradable resource, whose recycling use and conversion to high value‐added products can reduce the pressure on the environment and exert immense economic benefits. Herein, four kinds of common waste paper (e.g., printing paper, newspaper, straw paper and roll paper) were converted into cellulose‐based bioplastic membranes by using ionic liquid 1‐butyl‐3‐methyl‐imidazolium chloride as solvent. The cellulose‐based membranes are smooth and compact, and their mechanical strength is prominently improved about 3–100 times comparison with the original paper. The maximum tensile strength of the film (F4) is over 127 Mpa and its optical transmittance reaches 80% at 450–800 nm wavelength. Besides, this kind of cellulose‐based films have excellent biodegradability. Thus, the results demonstrated that the cellulose‐based bioplastic membranes stemmed from waste paper possess a magnificent application prospect. [ABSTRACT FROM AUTHOR]

Digital printing waste paper fiber/nanocrystalline cellulose/poly(lactic acid) composites, modified through γ‐methacryloxy propyl trimethoxy silane (KH570), isopropyl tri(dioctylpyrophosphate) titanate, sodium hydroxide, polyethylene glycol 6000 (PEG6000), and a composite silane coupling agent (KH570/PEG6000), were fabricated by melt blending and injection molding, and the effects of different modifiers on the properties of composites were studied. The results show that the mechanical properties of the modified composites were improved, and the best flexural strength, tensile strength, and impact strength were obtained by PEG6000, KH570/PEG6000, and KH570, respectively. Thermogravimetric analysis showed that the thermal decomposition performance of the composites treated by KH570 was relatively superior. Differential scanning calorimetry analysis demonstrated that the melting enthalpy and crystallinity of the modified material increased, while the cold crystallization temperature decreased. After modification, both water absorption and degradation showed a decreasing trend, especially KH570/PEG6000. Under the action of several modifiers, the diffusion coefficient, thermodynamic solubility, and permeability of composites were reduced to varying degrees. Furthermore, scanning electron microscopy demonstrated that interfacial adhesion and composite compatibility were improved with significantly fewer and smaller pores, as well as a fuzzy boundary among the three phases. [ABSTRACT FROM AUTHOR]

Nanocrystalline cellulose (NCC) was prepared from office waste paper (OWP) by sulfuric acid hydrolysis method in this paper and it was used to prepare a series of poly (lactic acid) PLA/NCC composites by using a dissolution method in solvent N, N‐dimethylformamide solution. The results indicated that with the addition of only 3 wt% NCC, the composites exhibited outstanding mechanical property. The tensile, bending and impact properties of the PLA/3NCC composite were improved by 8.2%, 13.1%, and 35.9% than those of pure PLA, respectively. On this basis, office waste paper fibers (OWF) were also used as a physical blended filler to enhance PLA/NCC composites to reduce the preparation cost of PLA composites and the perfect PLA/NCC/OWF sample was easily manufactured by melting–blending and injection molding. According to the crystallization and melting performance table, both NCC and OWF can act as nucleating agent to promote the crystallization properties on composites, while the blends did not have positive effect on thermal stability. Furthermore, the water absorption and degradation properties of PLA composites were also studied. This work not only provided a novel idea for the utilization of office waste paper but also successfully produced environment friendly composites with favorable mechanical properties and crystallization performance. [ABSTRACT FROM AUTHOR]

Combining recycling of paper wastes (WPs) with extrusion‐based additive manufacturing represents a sustainable route to cellular cellulose composites tailored for lightweight construction. Particularly, shear mixing of shredded WPs with an aqueous solution of a polymer binder like polyvinyl alcohol (PVA) yields aqueous pastes suitable for 3D printing. As a shear thinning additive, both WP and microfibrillated cellulose account for enhanced shear thinning and dimensional stability. Opposite to the formation of dense WP/PVA composites by melt extrusion, 3D printing of aqueous pastes produces cellular cellulose/PVA composites exhibiting hierarchical pore architectures. In spite of low densities around 0.8 g cm−3, high Young's modulus (2.0 GPa) and tensile strength (53 MPa) are achieved. Mechanical stability, water resistance, and even flame retardancy simultaneously improve by crosslinking with glyoxal and especially by mineralization. Multimaterial 3D printing combines the 3D dispensing of cellulose/PVA pastes with the simultaneous, staged, or subsequent spraying of aqueous water glass to enable mineralization of composite surface, bulk, and interlayers. Furthermore, the glyoxal‐mediated crosslinking affords thermo‐ and moisture‐responsive cellulose/PVA composites with programmable shape change induced either by heating at 100 °C or by exposure to moisture at 37 °C. [ABSTRACT FROM AUTHOR]

ABSTRACT Cellulose nanocrystals (CNC) are isolated from office waste paper using an alkali solution and a subsequent acid hydrolysis process. The Fourier transform infrared spectroscopy and X-ray diffraction (XRD) results demonstrate that ink and fillers used in the papermaking industry are almost totally removed after alkali treatments. The XRD results show that CNCs obtained after 2 wt % NaOH solution treatment and a subsequent hydrolysis process exhibit only a cellulose I crystalline structure, and the crystallinity index value increases around 42% with respect to initial office waste paper. Nevertheless, CNCs obtained after 7.5 wt % NaOH solution treatment and a subsequent acid hydrolysis process show a mixture of cellulose I and cellulose II polymorphs. The thermal analysis shows that the CNCs obtained after 7.5 wt % NaOH solution treatment and a subsequent acid hydrolysis process are thermally less stable than other samples, suggesting that the cellulose chains could depolymerize into low molecular weight sugar compounds. Even though the atomic force microscopy images confirm the presence of CNCs, the optical images show that some cellulose microfibers still maintain their structure. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45257. [ABSTRACT FROM AUTHOR]

The article offers research news briefs from chemical industry as of January 2015. It discusses development of processes for converting cellulose into n-hexane and other alkanes for using them as biofuels and bio-derived chemical building blocks by M. Dusselier and others, published in the journal "Energy and Environmental Science," and an approach for generating aluminium-aluminium bonding adhesives from waste office paper by Z. Zhang and other, published in the periodical "Green Chemistry."