Organic Functionalization Of Magnesium Hydroxide And Flame Retardancy In Different Substrates

Polymer materials are inexpensive and have a wide variety.Comparable to metal materials and inorganic non-metal materials,they have advantages such as low density,easy processing and easy forming,so they are widely used in various fields of life,becoming the largest outputs material in the national economy.However,most polymer materials are combustible and flammable.During combustion,the heat release rate and the flame propagation rate are high,and usually accompanied by molten dripping and the generation of toxic fumes,which has caused great harm to the environment and the safety of people's lives and property.Therefore,in order to improve the safety of the use of polymer materials,it is imperative to give them flame retardancy.In this dissertation,organic functionalization of magnesium hydroxide was used to prepare intrinsic and additive composite flame retardant materials.The specific research contents are as follows:1.Functionalized magnesium hydroxide CEPPM is prepared by the reaction of2-carboxyethylphenyl hypophosphite?CEPPA?and magnesium hydroxide?MH?;CEPPM is used to replace some monomers to prepare halogen-free and low-smoke intrinsic flame-retardant nylon 66?FRPA66?;the structure and morphology of CEPPM and FRPA66 were characterized by Fourier transform infrared spectroscopy?FT-IR?,nuclear magnetic resonance(¹H NMR,³¹P NMR)and scanning electron microscope?SEM?.The thermal stability,mechanical properties,and flame retardancy of FRPA66were characterized by TGA,limit oxygen index?LOI?,horizontal and vertical combustion?UL-94?and cone calorimetry?CCT?.The results show that compared with pure PA66,the copolymerized 9%CEPPM intrinsic flame retardant FRPA66 UL-94 is increased from V-2 to V-0;the LOI value is increased from 25.0 to 31.5;PHRR,THR and HRR have decreased by 40.6%,9.8%and 21.4%.2.Functionalized magnesium hydroxide BPMMA was prepared by the reaction of phenyl phosphate?BPA?,melamine and magnesium hydroxide?MH?;We add BPMMA and expandable graphite?EG?into ethylene-vinyl acetate copolymer?EVA?to prepare halogen-free and low-smoke EVA composite materials;The structure and morphology of EVA composites were characterized by fourier transform infrared spectroscopy?FT-IR?,nuclear magnetic resonance testing(¹H NMR and ³¹P NMR),scanning electron microscopy?SEM?;We also investigated the flame retardancy of EVA composites.The results showed that:PHRR of EVA-9 decreased from 1586.4 KW/m²to 185.2 KW/m²,a decrease of 88.3%;THR decreased from 553.6 MJ/m² to 11.4 MJ/m²,a decrease of 79.9%;and the TSP of EVA-4 decreased from 12.7 m² dropped to 3.9m²,a decrease of 68.2%.After the cone material calorimetry test of the reference material,there is no residual carbon,and the carbon layer of the composite material is up to 5 cm thick;the UL-94 test material of the control material has no grade,and the flame-retardant EVA composite material is V-0.3.Ethylenediamine tetramethylene phosphate reacts with urea and then reacts with MH to prepare functional magnesium hydroxide AEDMH;AEDMH and ammonium polyphosphate?APP?are used as additives to prepare low-density polyethylene?LDPE?composite resistance Materials;FT-IR,NMR(¹H NMR,³¹P NMR),high-resolution mass spectrometry?MS?,and scanning electron microscope?SEM?were used to characterize AEDMH and LDPE composite flame retardant materials;The flame retardancy of LDPE composites was investigated.The results showed that compared with pure LDPE,the PHRR and THR of LDPE flame-retardant composites were reduced by 64.2%and 27.3%,respectively;the LOI value reached 27.5,an increase of55.4%.