Preparation Of POSS Composites With Functional Groups And Study On The Combustion Properties Of Polypropylene

Silsesquioxane(POSS)is an organic-inorganic hybrid material.It is generally prepared by the hydrolysis and condensation of trihalo or trialkoxy silane.Its structure is irregular,trapezoidal,complete cage or Missing cage and other forms.In recent years,the research and application of POSS in the field of flame retardant have received more attention,but due to the complicated preparation process and low yield,its wide application is limited to a certain extent.In this paper,⁸NH₂-POSS with better flame retardant performance is selected as the monomer,and ATP-⁸NH₂-POSS composite material is prepared by intercalation reaction with aluminum dihydrogen phosphate(ATP),and ATP-⁸NH₂-POSS composite material is prepared.The characteristics of flame retardant used in polymers were studied,and the flame retardant mechanism was analyzed.The specific research work of the thesis is as follows:(1)Using KH550 as the raw material and tetramethylammonium hydroxide as the catalyst,white crystals appeared after the hydrolysis reaction,and ⁸NH₂-POSS monomer was isolated.It was characterized by ¹H-NMR,²⁹Si-NMR and other means,and the product was confirmed to be ⁸NH₂-POSS.The effect of reaction conditions on the yield of the product was discussed.When the reaction temperature is 50?,the amount of catalyst is 2ml,and the static time is 12h,the reaction yield is the largest,and the yield is 32%.(2)Using ATP and ⁸NH₂-POSS as raw materials,ATP-⁸NH₂-POSS composite was prepared by intercalation reaction,and the intercalation reaction composite ATP-⁸NH₂-POSS was characterized by SEM and FT-IR;ATP-⁸NH₂-POSS was analyzed by TG The thermal stability and thermal decomposition mechanism of the composite material were analyzed.(3)The resistance of ATP-⁸NH₂-POSS,ATP and ⁸NH₂-POSS to polypropylene(PP)was studied by vertical horizontal combustion(UL-94),oxygen index(LOI)measurement,cone and TG and other instruments.Burning effect.The results show that the three materials have a certain flame retardant effect on polypropylene.Compared with the single flame retardant ATP and⁸NH₂-POSS,the flame retardant performance of the ATP-⁸NH₂-POSS composite material is the best,and the mechanical properties of the material are also ⁸NH₂-POSS.The performance is relatively excellent.Subsequently,the effect of different ratios of ATP-⁸NH₂-POSS composite materials on the flame retardant properties of PP was studied;four different ratios of ATP-⁸NH₂-POSS/PP splines were prepared,and the test found that:as the content of ATP-⁸NH₂-POSS increases,The flame retardant performance of PP is better.When ATP-⁸NH₂-POSS is added at20%,the flame retardant performance can achieve better results.When ATP-⁸NH₂-POSS is added at 20%,the material oxygen index reaches 24,UL-94 level reached V-0 level.