Preparation and performance of flame retardant butyl tape compounded with phosphorus-based flame retardant agent

Abstract

Zinc oxide/melamine hypophosphate (MHS)/butyl tape premix (BTP) flame-retardant composites were prepared by mixing MHS, zinc oxide and BTP using mechanical blending method and the synergistic flame retardant effect between zinc oxide and MHS was investigated. The combustion performance and thermal stability of zinc oxide/MHS/BTP composites were studied by scanning electron microscope, limited oxygen index, cone calorimetry and thermogravimetric analysis, and the effect of zinc oxide on the adhesive performance of zinc oxide/MHS/BTP composites was studied by persistent adhesion and peel strength test. The results showed that the addition of zinc oxide could adjust the carbon formation and foaming process of the MHS/BTP composite and result in the generation of a complete gas chamber structure. The limited oxygen index of the composite increased from 28.5% to 33.0%, the vertical combustion grade of UL-94 increased from V-1 to V-0, the peak of heat release rate of the MHS/BTP flame-retardant composite could decrease by 66.7% at most, the total heat release decreased by 22.0%, the peak of smoke release rate decreased by 67.3% and the total smoke release decreased by 58.5%. The mass fraction of carbon residue of the MHS/BTP flame retardant composite increased from 25.58% to 40.41% and the maximum thermal decomposition temperature increased from 344.96 °C to 394.91 °C. The addition of zinc oxide would lead to a slight reduction of persistent adhesion and peel strength of the MHS/BTP flame retardant composite.

Keywords

• mechanical blending method
• melamine hypophosphate
• butyl rubber
• butyl tape premix
• zinc oxide
• synergistic flame retardant effect
• flame retardance