Study On Key Technology Of Antibacterial Functional Wheat Straw Fiber Mulch

It is the only way to realize the green and sustainable development of agriculture and promote the construction of ecological civilization to increase the research and development of green agricultural inputs and the resource utilization of agricultural waste.This study aimed at reducing pesticide such as efficiency,comprehensive utilization of straw and plastic film pollution problems of agricultural production,with wheat straw as raw material,carried out with a fully biodegradable property of wheat straw fiber orientation to improve the mulch type and antibacterial wheat straw fiber mulch manufacturing key technology research,and preliminary analyses the antibacterial mechanism of antibacterial typal wheat straw fiber mulch.The main research contents and results are as follows:(1)The basic model of wheat straw fiber mulch directional improvement key technology research.Using four factors five levels quadratic orthogonal rotation combination test method,with grammage,proportion of wheat fiber,neutral sizing agent and wet strength agent for impact factors,the dry tensile strength,wet tensile strength,sizing degree,air permeance and contact angle as the evaluation index,the wheat straw fiber on the mechanical properties of the mulch,barrier properties and the hydrophobic properties improvement,and carry on the verification test to each performance index.The results show that:when the parameter combination is grammage 55 g/m~2～65 g/m~2,proportion of wheat fiber 60%～70%,neutral sizing agent 0.9%～1.1%,wet strengthening agent1.3%～1.5%,dry tensile strength of the film≥1.8 k N/m,wet tensile strength≥0.8 k N/m,air permeance≤2μm/(Pa·s),sizing degree≥120 s,contact angle≥100°.The results were in the optimal range.When the parameter combination was:grammage 60 g/m~2,proportion of wheat fiber 65%,neutral sizing agent 1.0%,wet strength agent 1.4%,all performance indexes of wheat straw fiber wiper mulch met the requirements of coating substrate.(2)Study on manufacturing technology of antibacterial wheat straw fiber mulch.With 5 factors level 5 1/2 quadratic orthogonal rotation combination test method,adhesive concentration,wet film thickness,drug loading,acetic acid concentration,drying temperature as the impact factors,dry tensile strength,wet tensile strength,air permeance,sizing degree,contact angle as the evaluation index,optimize the antimicrobial type wheat straw fiber mulch manufacturing technology,and various performance indicators for validation test.The results show that:When the combination of parameters is adhesive concentration 1.4%～1.6%,wet film thickness 15μm～25μm,drug loading0.1 g/m~2～0.2 g/m~2,acetic acid concentration 2%～4%,drying temperature 35℃～45℃,dry tensile strength of mulch≥2 k N/m,wet tensile strength≥1 k N/m,air permeance≤1.4μm/(Pa·s),sizing degree≥200 s,contact angle≤90°.In order to satisfy the requirements of field laying,the process parameters were selected as follows:adhesive concentration 1.5%,wet film thickness 20μm,drug loading 0.15 g/m~2,glacial acetic acid concentration 3%and drying temperature 40℃.(3)Sustained release characteristics of antibacterial wheat straw fiber mulch.The release kinetics of antibacterial wheat straw fiber mulch was studied and the mechanism of sustained release of antibacterial wheat straw fiber mulch was analyzed.The results showed that the cumulative release of carbendazim from wheat straw fiber mulch manufactured by the optimized process could reach 87%-92%,and the release curve was in accordance with the Ritger-Pappas model.The release mechanism was the synergistic effect of drug diffusion and skeleton dissolution.(4)From the consideration of economy,machinery,environmental protection and so on,and through the study and analysis of mechanical properties,barrier properties,hydrophobic properties and slow-release properties,the manufacturing process of antibacterial wheat straw fiber mulch was designed.(5)Pot experiment.The antibacterial wheat straw fiber mulch treatment had significant control effect on soybean root rot.The plant height,weight and dry weight of antibacterial type wheat straw fiber mulch treatment group were 133.1%,144.9%and 113.8%of those of control group.Compared with the basic wheat straw fiber mulch,the antibacterial wheat straw fiber mulch has a more significant effect on improving pesticide efficacy and disease control,and provides a good environmental condition for soybean growth.