Heatfireprotection Polymer Coatings on the Basis of EPDM-40 with Additives

Abstract

Triple ethylene-propylene copolymers (EPDM) are used for the making of structural elements exposed to mechanical loads and are heat-resistant [1, 2], but their widespread use in aviation and shipbuilding equipment and other industries is limited due to Flammability. Double ethylene-propylene rubbers are practically limiting, and triple (EPDM), Dicyclopentadiene is used as the third component, due to the small content of double bonds in the side chains, have high heat resistance compared to diene rubbers [2], and therefore the issues of fire resistance of rubber-technical products based on them remain more and more urgent [3-7]. In [7] it is shown that if the values of the oxygen index (OI) and PP and EPDM are equal 17 % and 18.5 %, respectively, the coke numbers (CN) - 0 % and 0.5 %, and the copolymer is a PP/EPDM = 37,5/62,5 OI increases to 19.5% and CN up to 1.5 %. For copolymer PP / EPDM = 61.5 / 38.5 OI and CN are 21% and 3.4%, respectively, i.e. fire resistance in copolymers does not increase, which is an urgent problem. Polyolefins as it is shown in [7] and other works, at pyrolysis in soft conditions decompose practically without the rest, at thermal blows the mechanism of destruction changes and the carbonized rest is formed. The presence of cross-linked structures in the macromolecules of polyolefins also leads to the appearance of a carbonized residue. In work [8] the formulations of rubber mixtures resistant to wet chlorine, aqueous solutions of sodium hydroxide and sodium chloride, hydrogen, for the production of gaskets for electrolyzers and in [9] the effect of dithiophosphate accelerators on the complex properties of rubbers based on rubber grade EPDM-40. In [10] investigated the effect of a modified alumino-silicate intumescent microfiber filler kaolin microfiber (KMF) on the fire and heat protective properties (FHP) of vulcanizates based on ethylene-propylene-diene rubber EPDM-40. The compositions contained from 3 to 15 Weight Part (W.P.) KMV with a fractional composition of 25-110 microns and a fiber diameter of about 10 microns. As modifiers used a phosphorus boron containing oligomer (FBO), contributing to the increase of fireheat protective properties and multifunctional additive - hexachlor-p-xylene. It has been established that the modification of the kaolin microfiber leads to an improvement in the fire and heat protective properties at high temperature exposure: the rate of linear combustion decreases by 14%, the formation of the coke layer (CL) increases. It is shown that in conditions of erosion ablation, the fire-protective material has a 10 to 15% increase in tearing strength of CL, the time of onset of fire increases by 20-40% and the time of CL separation by 30%. In [ 11 ], the effect of HYPERLINK "https://translate.google.com/translate?hl=ru&prev=_t&sl=ru&tl=en&u=https://elibrary.ru/keyword_items.asp%3Fid%3D12826492" microcarbon fiber, a solution of FBO, HYPERLINK "https://translate.google.com/translate?hl=ru&prev=_t&sl=ru&tl=en&u=https://elibrary.ru/keyword_items.asp%3Fid%3D2483721" elastomers and HYPERLINK "https://translate.google.com/translate?hl=ru&prev=_t&sl=ru&tl=en&u=https://elibrary.ru/keyword_items.asp%3Fid%3D4285142" elastomeric materials on the fire-protective properties of EPDM-40 was investigated. The aim of the study was to investigate the processes of pyrolysis in the condensed phase, improving the properties of incombustibility and the creation of flame retardant rubber based on EPDM-40 for metal constructures.

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