Research On Equipment And Processof Continuous Glass Fiber Reinforced Polypropylene Prepreg Tape

Continuous fiber reinforced thermoplastic composite material(CFRTP)has great application potential in automotive lightweight design and aerospace due to its excellent performance,low cost and design flexibility.The melt impregnation process is a widely industrialized prepreg technology in the preparation process of CFRTP prepreg tape.Melt impregnation mold structure and impregnation process parameters determine the fiber dispersion effect and impregnation effect of the prepreg tape.Research on the mold structure and optimization of the process parameters play an important role in improving the performance of the prepreg composite material.Design the experiment plan through Design Expert software,and use the laboratory self-made production line to prepare the glass fiber reinforced polypropylene prepreg tape.Use the experimental results to analyze the influence of traction speed,pre-dispersing roll wrap angle,mold temperature on CFRTP dispersion,impregnation effect and mechanical properties.Then analyze the influence of dispersion and impregnation effect on mechanical properties,and optimize the best combination of process parameters for the mold.Based on the Wilson model,the prediction of fiber dispersion and broadening is established through experimental analysis,and the fiber crosssection distribution function derived from the Wilson model is used to predict the fiber dispersion uniformity of the prepreg tape.Based on Darcy's law and the Kozeny-Carman equation is used to describe the impregnation process of the resin melt in the fiber bundle.The Reynolds equation is used to calculate the melt pressure in the curved runner mold.Combine the Carreau model to characterize the resin melt viscosity.Combined with the spreading prediction equation of the dispersion model,the fiber impregnation model of the impregnation process is established.Based on the weibull distribution function,the fiber damage during the dispersion process and the impregnation process is analyzed,and the fiber fracture model is established.Combined with the theoretical model,the influence of mold structure parameters and process parameters on the degree of impregnation and fiber fracture rate is analyzed,and the influence of various parameters on the mold structure optimization process is analyzed to simplify the mold structure optimization process.The continuous glass fiber-reinforced polypropylene prepreg tape was prepared through experiments using two-structure melt-impregnation molds made in the laboratory,and various properties of the prepreg tape were analyzed.And through theoretical model analysis of the interaction between mold structure and process parameters.The results found that the two mold structures have their own advantages and disadvantages,and the optimization of the mold structure parameters can be achieved by taking advantage of each other to make up for the disadvantages.There is a certain interaction influence between the mold structure and some process parameters,which provides a certain reference for the optimization of mold structure parameters and process parameters.Combined with the theoretical model and the experimental results,the influence degree and interaction of the parameters of mold and process on the impregnation process are analyzed.Optimize the design of impregnation mold and impregnation process within a certain range,so that the impregnation process can achieve a lower fiber fracture rate and a higher degree of impregnation.