With the help of technology, natural rubber can be transformed into a variety of new materials

Natural rubber is an important industrial elastic raw material, and its excellent comprehensive properties make it irreplaceable. Developing new natural rubber composite materials is an effective way to extend its application field and expand its application range. Recently, Science and Technology Daily reporter learned from the Chinese Academy of Tropical Agricultural Sciences (hereinafter referred to as the Chinese Academy of Thermal Sciences), the processing institute of the natural rubber processing laboratory in the field of new natural rubber composite materials has made important progress.

Research and development of highly conductive composite fibers

MXene is the preferred material for energy storage fiber because of its high pseudocapacitance performance. However, the toughness of the fiber prepared by pure MXene is poor, and it is difficult to meet the requirements of special material preparation, which limits its large-scale production and application. By introducing carbon nanotubes (CNTs) into MXene fibers and using interfacial regulation and wet spinning technology, the research team of Natural rubber Processing Laboratory of the Processing Institute of the Chinese Academy of Thermal Sciences broke through the preparation technology of high toughness MXene fibers and developed MXene/CNT composite fibers with high toughness, high strength and high conductivity.

The research results were published in the international academic journal Carbon under the title "Carbon Nanotube-based MXene Fiber Capacitors with High toughness and high Conductivity".

On this basis, the research team made a breakthrough in the preparation technology of ultra-fine natural rubber fiber and highly conductive MXene/ natural rubber composite fiber by optimizing the formula and adjusting the process. The fiber is less than 200 microns in diameter, thinner than three strands of human hair, and has a 1,200 percent elongation when broken.

Dr. Tao Jinlong, leader of the scientific research team, said that the breakthrough of continuous microfine multifunctional elastic fiber technology based on natural rubber provides a good foundation for the development of "green" highly elastic, braided and wearable fibrous elastic electronic components.

To make inks that can draw circuits

MXene is one of the ideal materials for the fabrication of conductive circuits and electronic flexible devices, but the water-soluble MXene solution is easy to be oxidized at room temperature and can not be preserved for a long time.

To solve the above problems, the research team of Natural rubber Processing Laboratory of the Processing Institute of the Chinese Academy of Thermal Sciences broke through the preparation technology of MXene ink which can be stably preserved at room temperature by solvent compounding strategy, developed MXene ink with good fluidity and writing ability, and successfully drew circuits on the flexible substrate with ballpoint pen. This circuit has fast, accurate touch and can respond to water level measurement, which has potential application value in the field of flexible electronic technology.

The research was published in Nanoscale, an academic journal of nanoscience and technology research, under the title "Environmentally Stable MXene Inks that can directly write flexible electronic Products". It is reported that the scientific research team is accelerating the transformation of the results, carrying out the key technology research and development of "printable flexible composite conductive ink based on natural rubber /MXene".

Dr. Kong Na, the author of the paper, said that compared with the ink containing organic solvent, the composite conductive ink can give full play to the green advantage of natural latex aqueous solution, and realize the application of natural rubber in the field of flexible functional materials.

The highly conductive porous foam is prepared

Building energy storage devices with high power density and fast charging and discharging speed is the key to develop portable electronic devices. As a new two-dimensional highly conductive material, MXene has a unique advantage in the design of energy storage devices due to its high capacitance and good mechanical strength. However, intermolecular activity is reduced, hindering the transfer of electrons.

To solve the above problems, the research team of the Natural rubber Processing Laboratory of the Processing Institute of the Chinese Academy of Thermal Sciences successfully prepared MXene foam with highly interconnected channels by using the sacrificative template method. The abundant pore structure effectively expanded the specific surface area, provided enough effective sites for the electron movement between layers, and accelerated the electron transfer rate.

Dr. Zhang Jizhen from the Processing Institute of the Chinese Academy of Thermal Sciences introduced that compared with the current commercialized capacitors, the capacitors prepared by MXene foam showed much higher electrochemical performance than the traditional capacitors, especially in terms of power and energy density achieved a great breakthrough.

The research results were published in Small, an international academic journal in the field of nanomaterials, under the title of "Analytical Effect of pore size on electrochemical capacitance Performance of MXene Foam". In addition, the team constructed a flexible strain sensor with good sensitivity and sensing range using natural rubber foam and MXene as materials.

The person in charge of the Chinese Academy of Thermal Sciences said that the natural rubber processing laboratory of the processing Institute of the Chinese Academy of Thermal Sciences has made a major breakthrough in the field of high performance special natural rubber raw rubber processing. The laboratory has also newly established the direction of new natural rubber composite materials, in order to further explore the properties of natural rubber and expand its application field.