Synergistic Fire Performance Between Metal or Metal Filled Organic Coatings and Engineering Plastics

Abstract

Metal filled organic and EMI coatings affect the fire performance properties of engineering plastics. Zinc arc spray, zinc/epoxy, and zinc borate/epoxy coatings on modified-polyphenylene oxide (m-PPO) are particu larly effective. The results from non-flaming NBS smoke chamber tests show a dramatic reduction in smoke for zinc and zinc borate coatings, whereas a ZnO coating did not show the same effect. Heat release data (Radiant Panel) for these samples show lower Q values for zinc, zinc borate coatings compared to m-PPO, epoxy coated m-PPO and ZnO epoxy coated m-PPO. The Fs values for zinc and zinc borate coatings are low compared to a m-PPO control and ZnO coated m-PPO. Polycarbonate structural foam sheet was coated with epoxy coatings filled with zinc, zinc borate, or ZnO. NBS Smoke Chamber data in the non-flaming mode for zinc or ZnO coatings do not show an improvement in smoke produc tion, but a zinc borate epoxy coating does have a reductive effect on smoke. Ra diant Panel Q was low for all coated samples compared to a control. Fs values also were low for coated samples. From OSU heat release data the zinc borate/epoxy coating shows a low heat release rate and the zinc/epoxy coating a much delayed heat release rate. Data for smoke (2 min) was low for coated samples compared to a control, but for smoke (peak) only zinc borate demon strated the potential for significant smoke reduction.