Study On Properties Of Modified Starch Adhesive And Its Application In Biomass Seedling Trays

Seedling trays have been widely used in agricultural seedlings due to its simple operation and easy availability of raw materials.However,traditional seedling trays have poor air permeability and water permeability,are not easily degraded,and cause environmental pollution.Therefore,Biomass seedling trays with good degradability and environmental protection are increasingly used in agricultural planting.The important ingredient in the preparation of biomass seedling trays is starch adhesive.In order to improve the physical and chemical properties of biomass seedling trays and make them more suitable for the growth of seedlings,this article modifies the component starch adhesive in the seedling trays.Research shows that adding adhesive components in the process of preparing biomass seedling trays can improve the physical and chemical properties of biomass seedling trays.Firstly,corn starch is oxidized to synthesize starch adhesive.The influencing factors on the viscosity,fluidity,bonding strength,water resistance,drying rate and solid content of oxidized starch adhesive is discussed.The synthesized oxidized starch adhesive is added to seedling trays,the biodegradation rate of seedling trays was29.44%,the volume expansion rate was 62.31%,the moisture content was 14.06%,the shear strength was 0.8 MPa,and the optimal glue content was determined to be 4g.Secondly,in order to improve the biodegradation rate and water resistance of the biomass seedling trays,we modified the starch adhesive,and synthesized the grafted starch adhesive with VAC and MAA as the grafting mixed monomers.The water-to-powder ratio and acidity were investigated.The effect of decomposing time,grafting temperature,and the amount of grafting monomer on the performance of the adhesive,and using FT-IR,SEM,TGA,XRD to characterize the structure and morphology,the synthesized grafted starch adhesive is used to prepare biomass seedling trays.Compared with the biomass seedling tray prepared by oxidized starch adhesive under the condition of sizing amount,the biodegradation rate is increased by more than 10%,the volume expansion rate is reduced by 19.31%,the shear strength is increased by more than 1 times,and the optimal glue content was determined to be 3g.Finally,on the basis of the grafted starch adhesive,the graft-crosslinked starch adhesive was prepared by the double crosslinking method of TDI and borax,and the water-to-powder ratio,monomer dosage,crosslinking agent addition method,and crosslinking agent were explored.The effect of dosage on the graft-cross-linked starch adhesive,and the above two starch adhesives and the synthesized graft-cross-linked starch adhesive were used to prepare biomass seedling trays,and the physical and chemical properties of the three seedling trays were compared.Among them,the seedling tray prepared by cross-linked starch adhesive has the best physical and chemical properties.Its biodegradation rate is 41.19%,volume expansion rate is 34.72%,water content is 13.62%,and shear strength is 0.91 MPa and the optimal glue content was determined to be 2 g.In this paper,starch adhesive is applied to the preparation of biomass seedling trays,which provides a new choice for the application of starch adhesive.At the same time,the biomass seedling tray prepared by adding starch adhesive fully meets the needs of rice seedlings.The preparation of biomass seedling trays provides a new option.