Preparation And Study For Flame Retardant PVA Packaging Film

Polyvinyl alcohol?PVA?is a biodegradable packaging film polymer material.PVA,as the combustible and flammable materials in air,will also release a lot of black smoke during burning as well as most plastic,which greatly limits the PVA in the application of materials on the requirements of high flame retardant properties.In this paper,the application of three kinds of flame retardants in PVA flame-retardant packaging films was studied,and the flame-retardant mechanism of flame retardants in PVA packaging films was discussed.The following conclusions were obtained through experimental analysis:1.PVA flame retardant mechanism mainly contained the gas-phase flame retardant,condensed phase flame retardant and silica sol flame retardant three flame retardant mechanism.Several flame retardant mechanisms can be realized in the flame-retardant process,which is called synergistic effect-synergistic flame retardant.2.The gas-phase flame retardant mechanism of APP flame retardant played the main roles in PVA/APP flame retardant flame retardant system while condensed phase flame retardant mechanism may just play subsidiary roles.The results showed that LOI values of PVA flame retardant film reached 29%,and UL-94 reached V-0 rate when the APP content was 20%.This was because that the OP-10 improved the dispersibility and compatibility of APP in the PVA flame retardant packaging film to a certain degree.3.The synergistic effect of gas-phase and condensed phase flame retardant mechanism was existed in PVA flame retardant packaging film by the introduction of APP/MA compound flame retardant.The two mechanism supplemented and promote each other,which achieved the purpose of the common flame retardant promotes.The results showed that LOI values of PVA flame retardant film reached 34%,and UL-94 reached V-0 rate when the APP was 22% and the content of MA was 10%.The mutual crosslinking worm-like structure formed in the PVA film after adding APP and MA.4.A large number of Si-O-C bonds formed between SiO₂ in silica sol flame retardants and PVA molecules,which constituted a stable network structure and significantly improved the activation energy.The results showed that LOI values of PVA flame retardant film reached 32%,and UL-94 reached V-0 rate flame retardant standards when the content of SiO₂ was 28%.