Research On The Properties And Application Technology Of Biomass Cushioning Packaging Composites

In order to solve the problem of environmental pollution caused by plastic packaging composites,such as "white pollution",a new completely biodegradable biomass cushioning packaging composites with cellular microstructure was proposed.However,there are many problems about the biomass cushioning packaging composite need to be solved,such as the cushioning property of the biomass packing composite was poor,the development cycle of new product formulation using trial-and-error method was too long,and the original molding equipment can't meet the demand of the new biomass cushion packaging composites for the preparation process.In order to improve the cushioning property of the biomass cushioning packaging composites,the effect of fiber alkaline treatment,starch plasticizing modification and sisal fiber content on the cushioning property of the composites was investigated by analyzing the energy absorption efficiency-stress curves.The underlying influence mechanism of these factors was analyzed based on the cellular microstructure,hydrogen bonding strength and the compatibility between fiber and starch for the first time.Fiber alkaline treatment and starch plasticizing modification increased the compatibility between sisal fiber and thermoplastic starch(TPS),promoted the formation of dense cellular microstructure,thereby enhanced the cushioning property of the composites.And they also enhanced the hydrogen bond between sisal fiber and TPS,improved the interfacial adhesion strength between the sisal fiber and TPS,thus increased the cushioning property of the composites;With increasing fiber content,the cellular microstructure of composites becomes dense first and then loosens,resulting in initial enhancement and subsequent weakening of the cushioning property of the composites.The composite with 4:13 mass ratio of fiber and TPS exhibit the densest cellular microstructure and optimal cushioning property;After biodegradability tests for 28 days,the weight loss of the composites was 62.36%.It indicated that the composites had excellent biodegradation property and could be degraded under natural environment.It's found that the composites are a promising replacement for expandable polystyrene(EPS)as packing material,especially under large compression load(0.7-6 MPa).In order to solve the problem that the long development cycle and high research and development(R&D)cost of new composite caused by using the trial-and-error method during the process of R&D of the biomass composites formula.A new fast design method of biomass cushioning packaging composites formula with product property as the driving force was put forward.The mathematical prediction model for mechanical properties,density and cost of biomass cushioning packaging composites were established.In the process of R&D of new products of biomass cushioning packaging composites,the mathematical prediction model of the properties of the composites with new product property as the driving force can be used to design the formula of the composites quickly,thus greatly shortening the R&D cycle of the new products;On the premise of meeting the requirements of the mechanical properties of the new product,the density and cost of the composite can be optimized,thereby the lightweight design of the composite can be realized and the cost of the composite can be optimized.In order to meet the requirements of the new biomass cushioning packaging composite to the molding equipment,make up the deficiency of the original molding equipment and further improve the cushioning property of the biomass cushioning packaging composites.A molding equipment with dynamic controlled temperature field and pressure field was developed.It includes molding system,temperature control system and pressure control system.The temperature and pressure fields in the mold cavity of the forming equipment can be accurately controlled through the coordinated control of the above three systems.Through the simulation optimization design method,a series of optimized design were carried out to the original mold,which solved the problem that the original mold couldn't form the stable pressure field and the temperature field and pressure field in the mold cavity were uneven.Finally,a stable and uniform temperature and pressure field is formed in the mold cavity of the new molding equipment,and it can be controlled accurately and dynamically.In summary,the effect of fiber alkaline treatment,starch plasticizing modification and sisal fiber content on the cushioning property of the composites was investigated.The underlying influence mechanism of these factors was also analyzed.The cushioning property of biomass cushioning packaging composites was improved.A new biodegradable biomass cushioning packaging composite which can replace EPS as packing material was prepared;A new fast design method of biomass cushioning packaging composites formula with product performance as the driving force was established.A new molding equipment with dynamic controlled temperature field and pressure field suitable which was suitable for the new composites had been developed.All these provide theoretical and technical support for large-scale market application of the new biomass cushioning packaging composites.