Synthesis Of Composites Based On Black Talc And Their Applications As Functional Materials

Modification and resource utilization of clay minerals are the hotspot of mineral material and environmental protection.Black talc is a layer clay mineral with huge reserves in Jiangxi province,China.Its main chemical composition is Mg3(Si4O10)(OH)2,and displayed black or grey due to presence of graphenoid organic matter.At present,the main idea is to remove the organic matter in layered structure improving whiteness of black talc before application.In this study,a series of new composites were prepared directly on the bases of layered black talc.In this study,we investigated black talc adsorption properties based on its layered structure,combined mineralogy research methods with our major characteristics,which was no longer limited to whitening process.First,we systhesed dye stained talc,then filled it into marine polymer.Then mechanical properties,thermal properties,and shading performance of this polymeric material were studied.Second,we loaded the photosensitive material on the black talc layer,and electromagnetic wave performance of it was studied.Third,we loaded ferrite on the black talc layer,compared its performance with other electromagnetic wave materials,and microwave-assisted Fenton-like catalytic degredation of marine refractory industrial pollutants was also studied.Then we explored adsorption performance of acidified balck talc of simulated marine organic dye pollutants.And we intercalated photocatalyst into the interlayer,researched on the marine organic dye pollutants photocatalytic performance.These have broadened the application of black talc in marine pollutant treatment and marine materials.Through research,the following conclusions were drawn:(1)Stained talc was prepared by using dye(DR 28)and black talc,and then filled into ABS.Because black talc in low filling quantity can increase the toughness and strength of ABS,and dye can improve its compatibility with ABS,therefore,mechanical properties and thermal properties of stained talc/ABS were increased.Within a certain amount of filling quantity of dyed talc,the color of ABS deepened as filling quantity increased.But stained talc exists in the form of solid particles in ABS matrix,which can absorb part of the incident light,led to ABS dimmer.Combined modification,filling,enhancement and coloring,it shows that the stained talc fillers in polymer has a certain potential.(2)Talc/NiTiO3 composite was successfully synthesized.Lack of magnetic elements,both black talc and black talc/NiTiO3 composite materials exhibit low permeability,while eddy effect and tunnelling effect of NiTiO3 can increase dielectric loss.Electromagnetic wave absorption maximum RL of talc/NiTiO3 composite is-11.94 dB in 6.85 mm,the optimum thickness is in 6.3-7.3 mm range,the corresponding frequency is 13-18 GHz,which expand the application of talc and NiTiO3 in the electromagnetic wave absorption.(3)We synthesised black talc/NiFe2O4 composite,because NiFe2O4 has strong dielectric loss and magnetic loss,and reducing wave impedance,greatly improved its electromagnetic wave absorption properties.The optimum thickness is 2.97 mm,corresponding to the maximum RL value of 14.01 dB,bandwidth of RL<5 dB is 6.75 GHz,bandwidth of RL<-10 dB is 2.74 GHz.Compared with other absorbing materials,the performance of black talc/NiFe2O4 composite is better than others,which also expand the application of black talc in the electromagnetic wave absorption.And the electromagnetic wave absorbing properties of black talc/NiTiO3 composite materials can be improved by enhancing dielectric loss and introducing magnetic loss.(4)Talc/NiFe2O4 composite has high microwave absorption properties,and low surface area and adsorption.However,introduction of microwave irradiation will increase molecular thermal motion and system temperature,improving the Fenton-like reagent degradation of DMP.Thereby talc/NiFe2O4 composite can be applied to refractory marine pollutant removal.(5)Acidification can remove dolomite in black talc,while the layered structure of talc was retained.The simulation marine pollutant MB adsorption of acidified sample was consistent with Langmuir model.A new type of black talc/TiO2 nanocomposite was prepared by inserting TNBT into black talc layer and TiO2 particles were in-situ synthesised.Owing to increase of specific surface area and porosity of black talc/TiO2 nanocomposites,MB degradation rate can reach up to 99%within 40 min.In simulated seawater configuration,the ions in seawater with TiO2 can form the high oxidizing free radicals,so talc/TiO2 nanocomposites also showed good photocatalytic performance.At the same time,talc/TiO2 nanocomposites was similar to the photocatalytic performance of the newly synthesised TiO2.Therefore,talc/TiO2 nanocomposite is a recyclable and low-cost photocatalytic degradation material for organic pollutants.