The invention discloses a preparation method of upright polypropylene infusion bags, including the following steps: heating the barrel temperature of a one-step hollow molding machine to 160℃–250℃; injecting molten PP material into a bag preform mold under high pressure and performing pre-blowing to obtain a bag preform; transferring the uncooled preform directly to the blow molding station of the integrated machine for hot blow molding and subsequent cooling to obtain finished products. Adopting the hot blow process, direct hot forming reduces insoluble particles, enhances product stability, and eliminates preform storage and transfer procedures to lower the risk of foreign substance contamination. Products manufactured by this process feature low shrinkage, high bag elasticity, excellent impact resistance and gas barrier performance, reducing liquid leakage and improving yield. Blow molding is completed by utilizing residual heat of preforms without secondary heating, which shortens the molding cycle and cuts energy consumption.
Country Code: CN
Application Number: CN202211733361.8
