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A lignin-based PU coating was prepared for paper-based green packaging. Two representative diisocyanate were used to prepare the coatings. Due to the rigid aromatic, the physical properties of the TDI system reached the maximum below the lignin content of 40%. The HDI that contains flexible aliphatic chains alleviated the brittleness of coating, and it showed physical advantages when the lignin content was more than 50%. Owing to the high lignin content, the coating presented enhanced thermal stability. After coated with the lignin-based PU coatings, the dry tensile strength of coated paper was improved by 126%. Amazingly, the wet strength was increased from 0.31 to 12.6 MPa with an improvement nearly 40 times. Based on the coordination of lignin, Ag+ was introduced into the PU matrix, which imparted the coating with excellent antibacterial ability. The colony forming units of E. coli and S. aureus were both less than 1. However, no inhibition halo was observed, which indicated that the Ag was firmly anchored on the coating and the antibacterial ability is only available when the bacterial contact the coating surface. The lignin-based PU coating with favorable sustainability and properties shows great potential in paper-based green packaging fields. The prepared PU coating with high lignin content and firmly anchored Ag+ exhibits outstanding physical properties, thermal stability, and antibacterial property, which makes it an ideal candidate to be used in paper-based green packaging. [Display omitted] [ABSTRACT FROM AUTHOR]

Highlights • We set up an affordable method for the production inkjet printed conductive lines. • We tested plastic and paper as flexible sensors substrates using a consumer printer. • We characterized the printed lines morphology and their conductivity over time. • We defined an easy and rapid functionalization protocol for IDE printed devices. • Finally, we detected Ampicillin antibiotic in real milk samples by EIS measurements. Abstract Inkjet printing is an established technology that has been revisited in recent years for the low-cost and easy production of electrical sensing and biosensing systems. With this technique, it is possible to produce flexible microsystems on eco-compatible substrates such as polymers and paper. In this sense, we investigated the printing performances of a common office inkjet printer and of a commercial conducting ink, to produce aptamer-based electrochemical biosensors for antibiotics detection. During our analysis we characterized both the morphological and electrical properties of the printed electrodes, considering also their stability over time and tuning all the parameters to obtain reproducible micrometric systems. The produced devices proved to be able to undergo aptamer functionalization and to detect Ampicillin, a common used antibiotic, in few minutes with a LOD of 10 μg/ml in milk. Therefore, in this preliminary work we demonstrated the feasibility of low-cost customized inkjet-printed biosensors, and their possible use to prevent both antibiotic contaminations and antibiotic resistance development. [ABSTRACT FROM AUTHOR]

A paper-supported inorganic composite (PIC) separator is prepared by spraying Al 2 O 3 particles onto both surfaces of a commercial paper substrate. The as-prepared PIC separator shows excellent thermal stability without any shrinkage at 130 °C for 30 min, superior wettability towards the electrolyte, with a contact angle of 0°, and high ionic conductivity compared with that of the conventional polyethylene (PE) separator. The graphite|LiCoO 2 full-cells with the PIC separator exhibit good cycling and rate performance. In the nail penetration tests, the pouch cell assembled with the PIC separator shows high safety characteristics. Given the advantages of the PIC separator, it is a good potential replacement for the polyolefin separators used in high-safety lithium-ion batteries. [ABSTRACT FROM AUTHOR]

An anisotropic aerogel hot-extrusion strategy is designed to convert polyimide aerogels into aerogel-based paper. The multilayer interconnected aerogel-based paper exhibits excellent thermal stability and mechanical properties, and the mechanical properties remain great at high temperatures. This aerogel-based paper has huge application potential in the aerospace field. [Display omitted] • Multi-layer interconnected aerogel based paper was successfully prepared by anisotropic aerogel hot extrusion strategy. • Aerogel-based papers exhibit excellent thermal stability and stable mechanical properties (PI-1: 216.28 MPa at 25 °C). • The tensile strength of PI-1 was 3 times that of commercial polyimide paper and 24 times that of aramid paper at 400 °C. • Aerogel-based paper maintain stable mechanical property after 5000 cycles. The continuous improvement of papermaking technology has attracted widespread attention. However, the prevention of high-temperature decomposition and a subsequent decline in mechanical strength is still a significant challenge with current papermaking technology. Herein, a newly developed multilayer interconnected polyimide aerogel-based paper was successfully prepared via an anisotropic aerogel hot-extrusion strategy. Precursor solutions of highly rigid benzimidazole units containing intermolecular hydrogen bonds and linear rod-like benzimide units were first prepared. Anisotropic precursor polyimide (PAAS) aerogels with a thickness of 3 mm were then manufactured by unidirectional freeze-drying. Then, aerogel-based papers with a thickness of 40 μm and microstructure multilayer interconnected properties were obtained by a hot extrusion strategy and a thermal imidization process. This polyimide structural paper exhibited excellent thermal and mechanical properties. Through the design of micro and macro structures, the tensile strength of the aerogel-based paper was much higher than that of commercial paper at both room temperature and 400 ℃. This aerogel-based paper also exhibited high-temperature cycle stability, high flexibility, and good stretchable bending properties. The successful preparation of this aerogel-based paper demonstrates the feasibility of the hot extrusion strategy. This work provides a new papermaking technology method and broadens the application field of paper. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel dimer acid-based waterborne polyurethanes (DWPUs) were designed and prepared. • DWPUs were first used as multifunctional coatings for paper substrates. • Papers coated by DWPUs exhibited excellent water- and oil-resistances. • Alkyl and uniform membrane of DWPUs are critical to improve papers' properties. Paper derived from lignocellulose has great advantages over plastics as packaging material, nevertheless, the poor water- and oil-resistances of paper-derived products limited their application in high-end field. Herein, novel dimer acid-based waterborne polyurethanes (DWPUs) with different content of dimer acid-based polyester polyol (DG) were prepared and used as water- and oil-resistant coating for paper substrate. The effects of DG contents on water- and oil-resistances, mechanical properties and thermal stability of DWPUs coated papers were systematically investigated. When the content of DG reached up to 7 wt% (based on polyester glycol), the paper coated by DWPU exhibited 88.06% decrease in Cobb 60 value, 8.7 times increase in kit rating compared with uncoated paper. Meanwhile, DWPUs coated papers showed good mechanical properties and thermal stability. These improvements are attributed to the flexible long-alkyl chain, and six-ring structure of DWPUs as well as the continuous and homogeneous DWPU-derived membrane on the surface of paper. This study provides a new framework for the preparation of high quality, multifunctional, environmentally friendly water- and oil-resistant coatings for paper substrates. [ABSTRACT FROM AUTHOR]

Abstract: In this research the thermal stability of paper and its components are investigated, in order to evaluate the effect of the artificial weathering treatments, carrying on measurements of thermal gravimetry; also some SEM observations are performed to follow the degradative phenomena. Our work allowed to correlate the level of degradation of the artificially aged paper samples with that of the naturally aged ones. TGA curves of the weathered samples show changes in respect to the starting materials; particularly, the chemical oxidation appears as the most degradative action in respect to the other physical treatments. [Copyright &y& Elsevier]