Preparation Of Phosphorus-based Flame Retardant Spirocyclic Phosphate Bisphenol-s And Its Application In Resin

In recent years,the three major synthetic materials have developed rapidly,and they are rapidly replacing the traditional metal materials.They are widely used in China's chemical industry,and they bring a lot of convenience to human beings.But synchengcai is basically there are huge hidden dangers.In the application of polymer materials,the synthetic polymer is the most common and has the best mechanical properties,but the limit oxygen index of the synthetic polymer materials is generally less than 21%.And most of the polymer materials are composed of hydrocarbon oxygen and other elements,in the open fire or high temperature is very easy to burn.And it burns with smoke and droplets.In this paper,bisphenol-S,phosphorus oxychloride and pentaerythritol were used as raw materials to synthesize high flame retardant spiral-ring phosphate bisphenol-S copolymer by two-step reaction.The flame retardant was added into polyethylene and polypropylene to synthesize high flame retardant polymer.The effects of raw material ratio,reaction time and other factors on the yield of flame retardant and the flame retardant performance of flame retardant were studied.In the synthesis stage of flame retardants,the structure of flame retardants was characterized by infrared spectroscopy,and the thermal stability of flame retardants was analyzed by thermogravimetric analyzer.In the synthesis stage of polymer composites,the flame retardancy grade of composites and the limit oxygen index of composites were determined by vertical combustion apparatus and limit oxygen index apparatus.The mechanical properties of composites were measured by universal testing machine and impact strength tester.The process conditions of the suitable flame retardant pentaerythritol spirocyclic phosphate bisphenol-Scopolymer were determined by single factor test.In the first step,the reaction temperature was controlled at 110?,the suitable reaction conditions were:n(pentaerythritol):n(phosphorus oxychloride)=1:5,the reaction time was 6 h.In the second step,acetonitrile was used as the solvent,triethylamine as the acid binding agent,the temperature was controlled at 80?,the suitable reaction conditions were:n(pentaerythritol spirocyclophosphate dichloride):n(bisphenol s)=1:1.05,the reaction time was 8 hours.The maximum yield of the first step was 62.43%,and the maximum yield of the second step was 66.63%.The flame retardancy and mechanical properties of the composite reached the optimal value when the adding amount of flame retardant in polymer polypropylene and polyethylene was 25%.The thermal decomposition temperature of the flame retardant was 270?,which was higher than 200?of the common flame retardant.The experimental results showed that the oxygen index of the modified polypropylene composite reached 25.1%.The oxygen index of the modified polyethylene composite reached 23.9%.The impact strength and tensile strength of themodified polypropylene composite were 29.36KJ/m~2and 10.56 MPA The impact strength and tensile strength of the modified polyethylene composites were 18.17KJ/m~2 and 11.6 MPA.