Aging characteristics of drip irrigation belt in Xinjiang cotton fields and their effects on its recovery and recycling

The old drip irrigation belts in Xinjiang cotton fields are prone to damage and have low recovering efficiency when being mechanically recovered, as well as poor mechanical performance and short service life of the old materials used in the production of various new products. Therefore, experiments were carried out from the macroscopic mechanical properties and microscopic chemical composition changes of the old drip irrigation belt to explore how the changes in its mechanical and chemical properties affect the recovery and recycling of the old drip irrigation belt. Mechanical properties of the old drip irrigation belts were tested by statics and dynamics test methods. The experiment results of indicators about mechanical properties showed that the tensile strength, elongation at break, natural rebound rate, impact strength and other mechanical parameters of the old drip irrigation belt samples were significantly lower than the corresponding values of the new ones. Which will affect the tensile capacity of the drip irrigation belt when it is recovered in the field. Furthermore, X-ray energy spectrum and infrared spectrum methods were used to analyse the chemical composition changes of the old drip irrigation belt. The determination results of X-ray energy spectrum showed that the oxygen content of the new drip irrigation belt samples was 1.73%, while that of old drip irrigation belt samples reached 12.15% ~ 15.27%. Then, the infrared spectrum experiment results showed that there were significantly more carbon groups in the old drip irrigation belt samples than that in the new ones. In addition, the correlation between the mechanical properties and oxidation degree of drip irrigation belt samples was analyzed, results showed that there was a significant negative correlation between them. This study results can provide basic data and theoretical guidance for the research and development of drip irrigation belt recovery equipment in Xinjiang cotton field, the research of rapid detection method of drip irrigation belt aging, the manufacture of anti-aging drip irrigation belt and the cyclic utilization of old materials.