Study On Preparation And Thermal Insulation Properties Of Intumescent Thermal Insulation Emrgency Materials

With the development of society,chemical plants have been developing towards the trend of industrial park large-scale and centralized.Once a fire occurs in the storage tank area,the consequences of the accident may be more serious and the harm will be further deepened,so the protection between adjacent storage tanks is extremely important.In this context,this paper develops a sprayable emergency thermal insulation material.When a fire occurs,the material can be sprayed on the surface of adjacent storage tanks to block heat radiation between adjacent storage tanks and prevent the spread of fire.During the synthesis of Potassium polyacrylate(K-PAM),Hectorite modified with silane coupling agent(KH-570)was added to prepare heat insulating material PPMH(Potassium polyacrylate?organic modified hectorite).On this basis,three intumescent flame retardants(IFR)were added in the polymerization process additionally,and three thermal insulation materials PPMHI(Potassium polyacrylate?organic modified hectorite?intumescent flame retardant)were prepared respectively,namely PPMHI-L(Lotus root starch),PPMHI-T(Tea saponin)and PPMHI-PT(Phytic acid?tea saponin).The aggregation state of the material was investigated by Fourier transform infrared spectroscopy(FTIR)and X-ray photoelectron spectroscopy(XPS).In order to explore the thermal insulation performance of the material,the temperature test,scanning electron microscope(SEM),thermogravimetric test analysis(TGA)and fire resistance test are completed,the finding results are as follows:(1)Research on PPMH thermal insulation materials.It was found by FTIR that hectorite was successfully intercalated by KH-570,and the modified hectorite also participated in the polymerization of potassium polyacrylate.A large number of-OH and-COOH hydrophilic groups were found in the material.The optimal ratio of initiator(ammonium persulfate),chain transfer agent(sodium bisulfite)and additive(modified hectorite)in the synthesis process was explored by designing an orthogonal table.The results show that when 0.11wt%initiator+1.45wt%chain transfer agent+1.36wt%additive are satisfied,the material meets the optimal choice of viscosity and thermal insulation performance.In addition,thermogravimetric-infrared(TG-IR)analysis revealed that thermal decomposition products of the material are mainly H₂O and CO₂.(2)Research on PPMHI-L thermal insulation material.By FTIR and XPS,the successful polymerization of the material is illustrated.Using the cone calorimeter to study the heat transfer process of PPMHI-L material,the study found that when the proportion of lotus root starch was 0.31%,the thermal insulation material PPMHI-L had the best thermal insulation performance.Compared with PPMH,the material added with intumescent flame retardant reduces the maximum temperature by 35.4%-41.6%.It can be concluded from SEM that with the increase of lotus root starch content,the char layer formed after the material heated is more stable.(3)Research on PPMHI-T thermal insulation material.PPMHI-T was characterized by FTIR and XPS.It was found that the organic modified hectorite and the intumescent flame retardant were involved in the polymerization reaction.The heat transfer process of PPMHI-T material was studied by cone calorimeter.It was found that the final back surface temperature of the PPMHI-T2(0.54wt%IFR)coated steel sheet was only about165.2°C.In addition,with the increase of the intumescent flame retardant,its water absorption rate starts to decrease,and the fluidity becomes poor.Combining thermal insulation and water absorption,PPMHI-T2 performs best.According to the TGA data,the thermal degradation of the material can be divided into two stages.The thermal degradation products of the material are mainly CO₂,H₂O and NH₃.The carbon residue of PPMH was 27.8 wt%,and the carbon residue of PPMHI-T2 was higher,about 38.7wt%.By SEM-EDS analysis,it was found that the char layer structure of PPMHI is more compact.The swelling height of the char layer of PPMHI-T2 is about 2 cm higher than that of PPMH.With the increaseing residual carbon content in PPMHI-T the char layer structure becomes more stable.(4)Research on PPMHI-PT thermal insulation material.It can be seen from FTIR and XPS that the modified hectorite and the intumescent flame retardant participate in the polymerization reaction.The heat transfer process of PPMHI-PT material was studied by cone calorimeter,and it was found that the steel plate surface of PPMHI-PT3(0.81wt%IFR)was only 173?.The thermogravimetric test found that the peak value of the derivative thermogravimetric curve of PPMHI-PT increased due to the addition of flame retardants.From the SEM-EDS analysis,it can be found that the char layer became denser with the increase of the flame retardant content,which is about 4 cm.