PTC-thermistors Based on Polymer Composite Material for Use in the Agricultural Sector

Abstract

The agro-industrial complex plays a key role in the domestic economy and requires improvement and modernization of existing and creation of new technologies. The introduction of intelligent and automated systems and digital methods leads to the need for the development of control systems and sensors that ensure accuracy and operational stability. (Research purpose) The research purpose is in developing the polymer composite materials based on an epoxy oligomeric binder for use as PTC sensors. (Materials and methods). The compositions were mixed according to the calculations of generalized parameters of the structure of a dispersed-filled polymer composite material. The method of thermomechanical analysis was used to study the dependence of electrical resistivity on temperature for samples of composite material based on ED-20 epoxy resin with different filler concentrations. The resistance was measured by multimeter to the contacts of the sample. Copper fabric was used as contacts. (Results and discussion) The article considers the possibility of using the obtained composite materials on the example of the technological process of grain drying, where the temperature of the drying agent can vary in the temperature range from 40-50 to 120-140 degrees Celsius. There is a possibility of «programming» PTC sensors based on polymer composite materials by varying the qualitative and quantitative composition to solve the necessary tasks and the operation of PTC sensors in different temperature ranges. (Conclusions) The developed samples of polymer composite materials have the prospect of application as PTC sensors for various technological processes of agriculture. The developed samples of various compositions are sensitive to the required temperature ranges.