Study On The Preparation And Properties Of Rice Straw Fiber-based Grass Suppressing Mulch Film

Weed control in paddy fields is one of the important links in rice planting.Film-covered rice cultivation can control weed growth,reduce fertilizer loss,and provide a new planting model for green rice cultivation.However,the non-degradability of plastic mulch film has caused serious ecological and environmental pollution.China produces a large number of crop stalks every year.Abandonment of stalks have brought a series of resource and environmental pollution problems.This paper focused on the preparation of a degradable straw fiber base film using crop straws,which was mainly used for the suppression of weeds in rice cultivation.While reducing the use of plastic mulch film,the waste straw is recycled.In this paper,after the straw fiber was depolymerized,straw fiber-based grass suppressing mulch films were prepared by wet papermaking process and the properties were tested.The main research work of this paper includes the following aspects:Biological deconstruction is based on the activity of microorganisms to decompose,transform and destroy straw fiber.The microorganisms decomposed some easily decomposable organic matters such as pectin,wax and oil on the surface of the fiber at first.With the penetration of hypha,the absorption peaks of straw fiber at 1724 cm^-1 and 1233 cm^-1disappeared,indicated that the linkages between rice straw were damaged.With the naked leakage of cellulose and hemicellulose,the holocellulose was gradually degraded,and its content gradually decreased.The effects of different microorganism inoculation amount and treatment time on the pulping performance of straw fiber were studied.Comprehensively considerd the loss of materials and the changes in mechanical properties of straw fibers to determine the biological treatment conditions,it was found that the energy consumption of straw pulping was greatly reduced and the mechanical properties were slightly improved after biological treatment.Straw fiber-based material was prepared by sizing in the pulp and finishing after coating.When the coating amount of chitosan was 2.0-2.5 g/m²,the dry tensile strength of the material was 31.92 N and the wet tensile strength was 10.36 N.The burst resistance is 136.00 k Pa and the tear strength is 352.27 m N.A pot experiment was performed on the prepared material,and the results showed that the herbicidal effect was very significant,compared with that of the bare land control 76.19%reduction in weed growth,could achieve the effect of reducing medicine and reducing weeding costs.In addition,the tillering ratio was increased,and the tiller number of the straw-fiber-based sample was 9.63,which was 0.75 higher than that of the bare soil control,and 1.13 higher than the commercially available sample.