Study On Biomass-Based Ammonium Phosphonate And Macromolecular Ammonium Phosphonate Flame Retardant Flame Retardants For Cotton Fabrics

Cotton fibrics products are materials commonly used by people,and are widely used in apparel,furniture materials,bedding and other fields.However,cotton fibrics are very flammable.Fires hazard caused by cotton fabric burning each year cause huge economic losses.Therefore,study on flame retardant cotton fabric is of great significance.Halogen,phosphorus,nitrogen,silicon,including some hydroxides and metal compounds are the mainstream flame retardant commonly used at home and abroad.Some developed countries have begun to ban the use of halogen-containing flame retardants.Nitrogen-containing compounds are generally used as synergists for phosphorus-containing flame retardants.Silicone flame retardants have low flame retardant efficiency,so they have high flame retardant efficiency.Phosphorus-containing flame retardants that are corrosive and have good compatibility with polymer materials have become a research hotspot,and the current market demand for phosphorus flame retardants is very large.Various inorganic flame retardants,such as Aluminum hydroxide,boric acid,antimony oxide and molybdenum-based compounds are cheap,non-volatile,have good thermal stability,have little impact on the environment and people,and can effectively control smoke,but the amount of a large amount seriously affects the performance of the material and its low flame retardance efficiency.With the increasing depletion of petroleum resources on the earth,the search for the use of sustainable biomass resources to develop new phosphorus-containing flame retardants has become a new research hotspot.Based on this research,two types of biomass-based phosphorus-containing durable resistances have been designed.The flame retardant of biomass is generally difficult to obtain.Therefore,a polymer-based polyvinyl alcohol-based phosphorus-containing environmentally friendly and durable polymer flame retardant was designed.Each flame retardant All contain(-PO-NH⁴⁺)active groups,which can react with the hydroxyl groups on cotton fiber to form a strong P-O-C covalent bond to improve durability.The research content of this article mainly includes:?1?Synthesis of ammonium salt of sodium glutamate tetramethylenephosphonic acid flame retardant and its application on cotton fabrics.In this study,a biomass-based ammonium salt of sodium glutamate tetramethylenephosphonic acid?ASGTMPA?was synthesized for cotton fabrics.The structure of ASGTMPA was characterized by NMR¹H,NMR ³¹P,NMR ¹³C and Fourier infrared?FT-IR?spectrum.The results show that ASGTMPA can bind to cellulose through P-O-C and-COOC-covalent bonds.TG and TG-IR analysis showed that the thermal cracking temperature of the cotton fiber treated with ASGTMPA was reduced,showing a typical condensed phase flame retardant mechanism.The ASGTMPA flame retardant changed the thermal cracking route of cotton fabrics and promoted the dehydration of cellulose to form carbon,and reduce the generation of flammable gases.Cone calorimetry test showed that the PHRR and THR of cotton fabric treated with ASGTMPA were lower than that of unfinished cotton fabric,indicating that ASGTMPA treated cotton had good flame retardant properties.In the vertical combustion test,when the concentration of ASGTMPA is 30%,the treated cotton fabric has no smoldering or continued burning,the damage length is 35mm,the limiting oxygen index reaches 39.5%,and after 50 LCs,it is 26.3%;SEM images show The morphology of the original and treated cotton fibers is similar.The XRD test shows that the crystal structure of the cotton fiber has not changed much,and in the strength test,it can be seen that the ASGTMPA flame retardant has not greatly affected the physical properties of the cotton fabric,and the strength and feel of the cotton fabrics remain good.?2?Synthesis of vanillin ethanolamine ammonium phosphate flame retardant and its application on cotton fabrics.This research designed and successfully synthesized a vanillin-based durable flame retardant vanillin ethanolamine ammonium phosphate?VEAAP?flame retardant,which contains?-PO-NH4+?active groups during the synthesis of the flame retardant without using formaldehyde,it can form P-O-C covalent bond with cotton fabrics.The structure of VEAAP was characterized by NMR1H,NMR 31P and NMR 13C.The FT-IR test showed that VEAAP was successfully grafted onto cotton fabric via P-O-C covalent bond.Through TG analysis,TG-IR analysis,vertical combustion analysis,limit oxygen index measurement analysis and cone calorimetry analysis,the flame retardant performance and washability of VEAAP treated cotton were characterized.The limit oxygen index of 20%VEAAP treated cotton reached 36.7%.After 50 LCs,the limit oxygen index is still 28.2%.VEAAP changed the thermal cracking route of cotton.The flame retardant formed phosphoric acid and polymetaphosphoric acid during the cracking process,which promoted the formation of carbon and greatly improved the carbon The flame retardancy of cotton fabrics and the release of flammable gases from treated cotton are greatly reduced.It was observed by SEM that the morphology of the treated cotton fiber and the untreated cotton fabric did not change significantly,only slight swelling occurred.XRD test showed that the crystallization of VEAAP-treated cotton fabrics was not greatly affected.?3?Synthesis of polyvinyl alcohol ammonium phosphate flame retardant and its application on cotton fabrics.Hydrogen peroxide was used to degrade PVA,and phosphoric acid and degraded PVA are used as raw materials to successfully synthesize polyvinyl alcohol phosphate ammonium?PVAAP?flame retardant for cotton fabrics.The structure of PVAAP flame retardant was characterized by nuclear magnetic resonance?1H NMR,13C NMR and 31P NMR?.FT-IR and washing resistance show that PVAAP flame retardant is successfully grafted onto cotton fabrics.The limit oxygen index?LOI?of the cotton fabric treated with 24%PVAAP reached 41.2%,and remained at 26.3%after 50 LCs,which indicates that 24%PVAAP flame retardant can be used as a durable flame retardant.The vertical burning test showed that the cotton fabric treated with PVAAP had no smoldering.The cone calorimetry test showed that the peak heat release rate?PHRR?and total heat release?THR?of cotton fabrics treated with 24%PVAAP were significantly reduced compared to the control cotton.Thermogravimetric?TG?and thermogravimetric infrared?TG-IR?spectroscopy showed that the initial decomposition temperature and the final decomposition temperature were greatly reduced,and PVAAP flame retardant changed the thermal cracking route of treated cotton.X-ray diffraction pattern?XRD?and scanning electron microscope?SEM?showed that the crystallinity of PVAAP-treated cotton fabrics decreased,probably because the PVAAP molecules entered the interior of the cotton fibers,because phosphoric acid and poly Due to the damage of metaphosphoric acid,the structure of the fiber treated with PVAAP flame retardant remains good,so PVAAP has potential application value.