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The possibility of producing pulp-and-paper materials with improved performance characteristics via exposing paper to the field of a unipolar corona discharge has been explored. It has been shown that the improvement of the physicomechanical properties of a pulp-and-paper material under the action of an electric field is associated with the orientation of the structural elements of the material and the strengthening of the bonds between the mutually approaching cellulose fibers. The enhancement of the barrier characteristics of the paper exposed to a unipolar corona discharge is attributed to the formation of an energy barrier, which is overcome at the expense of the driving force of the spreading of the liquid over the surface of the material. [ABSTRACT FROM AUTHOR]

In this study, the effect of heat treatment on barrier and functionality of polyolefin-coated papers was investigated. The aim was to find the optimal improvements on barrier without losing the applicability of the materials due to physical damages. The results of the study proved considerable improvement in barrier characteristics of the structures. Both water vapor and oxygen transmission rates of LDPE-coatings decreased linearly following the set-temperature until 200°C. At this point, the treatment caused a continuing decrease in oxygen transmission achieving 10 × lower transmission levels than the untreated structure, whereas moisture transport faced corresponding but lower increase. This was considered to be caused by the difference in diameter of the H2O and O2 molecules; the smaller water molecules are able to penetrate between spherulites, whose size increased due to higher treatment temperature followed by cooling. [ABSTRACT FROM AUTHOR]

• Fabrication of flexible paper temperature sensors with 658.5 Ω/°C. • Temperature sensitivity of 658.5 Ω/°C, which is 14 times higher than that of sensor with polymer substrate (46.0 Ω/°C), for the temperature range of 30–42 °C. • Reliable process against atmospheric humidity. • Implement a body-attachable temperature patch for wearable thermometer. A highly sensitive, flexible, and wearable paper-based temperature sensor is fabricated using printing paper and poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) solution. It exhibits a negative temperature coefficient and is implemented in a new band-like body-attachable thermometer. Compared to the polymer substrate, the use of hydrophilic and flexible paper substrate facilitates significantly superior sensitivity and simple fabrication. The paper sensor is fabricated by depositing PEDOT:PSS onto the paper with an 80 g base weight for 40 s, which is covered with a 50 μm film to protect it from humidity. This is followed by a heat treatment at 150 °C for 10 min. The paper sensor exhibited an electrical conductivity of 0.48 Ωcm−1 at room temperature with a linearity of 99.86 %. Remarkably, its sensitivity is 658.5 Ω/°C, which is 14 times higher than that of sensor with polyimide substrate (46 Ω/°C), for the body temperature range of 30–42 °C. The paper-based temperature sensor is implemented in a body-attachable patch for a wearable thermometer, which is simply connected with a circuit part for signal processing and the results are transferred to a phone via Bluetooth. The proposed inexpensive sensor is potentially useful for a wide range of flexible electronics and healthcare applications. [ABSTRACT FROM AUTHOR]