Сельскохозяйственные машины и технологии (Jun 2016)
Innovative agricultural materials
Abstract
Development of ecodegradable materials and use of them in innovative technology of sowing of seeds of grain crops in a tape isan important and actual problem of polymeric chemistry. Material is affected by programmable destruction under the influence of natural factors taking into account the biochemical processes in a plant. At the present time in literature there are no the data about polymeric materials which can operate plants biochemical processes when contacting to root system of directly in the soil. The authors developed compositions on the basis of synthetic polymer - low density polyethylene (LDPE) and biodegradable polymer - a polylactide (PLA). Thermophysical properties of ecofilms change under the influence of ultra-violet radiation. Photooxidation leads to cracking of samples with the raised maintenance of PLA. Temperature of melting of PLA decreases from 165 to 152 degrees Celsius (in some compositions to 137 degrees) and crystallinity degrees lower on average by 20 percent. Thus the most considerable decrease in crystallinity (about 30 percent) is noted in composition with a ratio of components of 50:50 mass percent. A composition formulation affects on the speed of destructive influence of moisture and an ultraviolet. The speed advantage of these processes is characteristic for the compositions containing from 30 to 60 mass percent of PLA. The soil samples with the maintenance of PLA more than 30 mass percent will be in less time exposed to biodegradation. Composition 50:50 has the greatest loss of weight equaled 18 percent. For other samples relative loss of weight makes 5-10 percent. The test for biodestruction showed considerable change of properties of polymeric samples of PLA- LDPE depending on mix composition. It means that it is possible to select such ratio of components at which material properties would conform to requirements imposed to agricultural appointment films.
