Research On Halogen-Free Flame Retardant Polyolefin Flooring Materials

This article used maleic anhydride grafted EVA(75% of it is EVA whose VAc content is 18%,25% of it is EVA whose VAc content is 32%) as matrix resin, and then filling 70% Al(OH)3 in EVA to manufacture the halogen-free flame retardant polyolefin flooring materials. This article has been tried several formulas through experiments, besides has a deep study on the content of the various components in the formulas and the processing methods and conditions of the halogen-free flame retardant polyolefin flooring materials. Using test equipment such as universal materials testing machine, oxygen index tester, smoke density tester, hot air aging instrument and akron abrasion tester, this article inspect the material’s performance such as mechanical properties, oxygen index, smoke density, changes in mechanical properties after hot air aging, akron abrasion. Through the above methods we got the best formula and processing methods and conditions.1. When the material’s content of Al(OH)3 is 70%, the oxygen index of the material is better than those whose content of Al(OH)3 is 50% or 60%, the oxygen index achieved a high level 34, in full compliance with the technical requirements. Among polymer materials including LLDPE, Vista-elastomer, EVA and EAA, the article choosed EVA as the matrix resin of the halogen-free flame retardant polyolefin flooring materials. When the ratio of the EVA whose VAc content is 18% and the EVA whose VAc content is 32% in matrix resin is 3:1, the mechanical properties of the material achieve the best, with a tensile strength more than 12MPa and a breaking elongation more than 100%2. The mechanical properties of the halogen-free flame retardant polyolefin flooring material are significantly influenced by its processing methods. Compared to the product processed by twin-screw extruder, those which is processed by closed mixer have better mechanical properties, both the tensile strength and breaking elongation of the material processed by closed mixer have a 10% increase. When the mix temperature is 150℃, the matrix resin EVA has better fluidity, the raw material can mix with each other better, at the same time this processing temperature can avoid the raw material from being burned, it can ensure the product’s good exterior.3. The article inspect the hardness, low temperature performance and mechanical properties of the material by testing on its shore A hardness, brittleness temperature and stress and strain. Here is the testing results: the density of it is 1.356g/cm3,the shore A hardness of it is 93, its brittleness temperature is -22℃, its tensile strength is 12.05MPa, its breaking elongation is 107.36%.4. The article also inspect the burning performance and Abrasion resistance of the halogen-free flame retardant polyolefin flooring material. Here is the testing results:its oxygen index is 29.5, the smoke density is 2.941176%, the akron abrasion is 0.688cm3/1.61km5. The article inspect the hot air aging performance of the halogen-free flame retardant polyolefin flooring material, and compared the shore A hardness and stress and stain performance before and after the hot air aging. Here is the results:after the hot air aging, the shore A hardness of the material changes to be-6, its rate of change on tensile strength is-13%;its rate of change on breaking elongation is-9%...