Performance And Mechanism Of Wood-based Composites Reinforced With Red Pottery Clay

Wood-based composites combine the advantages of both woody units and functional units.In order to explore the new ways to enhance the performance of wood-based composites,the performance and mechanism of wood-based composites reinforced by red clay were studied systematically.The effects of red clay and modified red clay on wood-plastic composites and the properties of the wood-based foam composites were investigated.The influence of the red clay on the properties of the polystyrene/nanometer cellulose crystal composite film was further investigated.The aim of this paper is to establish the best quality ratio of red clay and modified clay to improve the functional characteristics of wood-based composites,realize the efficient use and recycling of wood residues and plastic,and improve the preparation process of wood-based composites,And gives the new performance characteristics of wood-based composites,expand the multi-functional development of wood-based composite materials.The main contents and results are as follows:(1)Through the research of RPC inorganic filler component analysis and preparation,using SEM,XRD,and rapid analysis of chemical composition of nonmetallic materials,whiteness test,viscosity test and calcination experiments,the characteristics of Nenjiang basin unearthed Neolithic late RPC was confirmed.The component mass ratio was 6.57wt%MgO,16.93wt%Al2O3,68.23wt%SiO2,8.27wt%Fe2O3.The RPC was prepared according to the proportion,then it was refined into clay,finally into RPC inorganic filler by high temperature anaerobic calcination;and the surface morphology and viscosity characteristics of RPC was investigated;the RPC high temperature anaerobic calcination mechanism was revealed.All the above study set the foundation of RPC as the wood-based composite inorganic filler.(2)Through the study of the preparation and properties of high density polyethylene(HDPE)wood-plastic composites reinforced with RPC by SEM,mechanical properties test,shrinkage test,friction test and cone calorimeter test.The study focuses on the effects of different amount of RPC on properties of wood plastic composites.The results:SEM observation indicates that under 2000X,when the addition of RPC was 5wt%,the distribution of RPC is uniform in the fracture surface.With increasing the amount of RPC,the phenomenon of agglomeration under 500X was observed.The mechanical properties,density and shrinkage analysis showed that when the RPC content was 5wt%,the bending strength increases by 7.5%;the flexural modulus increases by 2.64%;the tensile yield stress increases by 26.51%;the tensile strength increases by 0.2%;while the elongation decreases by 12.22%;the impact strength increases by 18.81%;density increases,shrinkage rate decreases.The friction performance tests showed that the friction reaches the maximum when the RPC addition amount was 5wt%:the friction coefficient was 0.28;the friction coefficient increases by 133.33%,and with better skid resistance.Cone calorimeter tests show that when the RPC content is 10wt%,WPCs material TTI extends 5s;HRR decreases by 15.25%;EHC decreases by 3.48%;MLR decreases by 19.05%;THR reaches 79.33 MJ·m-2.The decrease was 13.72%,and TSP and SPR decreases by 25.37%and 27.78%respectively.Comprehensive performance showed that RPC can effectively improve the mechanical properties of composite materials,increased the friction coefficient of the material,enhanced the anti-slip performance of materials,and improved the combustion performance and the amount of residual carbon material,and the combustion suppression effect,which can also effectively optimize the performance of wood-based composites.(3)Based on the research of preparation and properties of HDPE/wood-fiber composites reinforcing mRPC,RPC was modified with silane coupling agent(KH-560),then the mRPC/HDPE/wood-fiber composites was prepared.Through the testing of dynamic mechanical properties(DMA),thermal stability(TGA)absorption characteristics,UV accelerated aging,mechanical property test and spectrophotometer measurement,the study focuses on the influence of different mRPC content on the properties of composites,revealing the RPC organic silane modification mechanism.The results:moisture absorption tests showed that the moisture sorption isotherms appear "S" curve upward,and the phenomenon of hygroscopic hysteresis.DMA and TGA test showed that the composite performance was the best when adding 5%mRPC,the storage modulus being 3264MPa,loss modul was being 2084MPa.The thermal degradation temperature was obviously increased.UV accelerated aging analysis showed that in the aging process of 3000h,the mechanical properties lose the least when adding 5wt%mRPC.The flexural strength,the flexural modulus,the impact strength were 63.17MPa,3284.17MPa,and 12.85MPa respectively;spectrophotometer test results showed that this in the aging stage,?L*and ?E*increase.The composite surface with 5%mRPC fades least.It also showed that mRPC was a rigid structure in composite material,and the rigidity was enhanced obviously.The thermal stability and anti-aging properties of wood-based composites were effectively enhanced.(4)The preparation and properties of modified wood-based foam composites were studied.The mRPC/polypropylene(PP)/wood fiber foam composites were prepared by high temperature hot pressing at 180?.Through SEM,mechanical properties test,shrinkage porosity and water absorption rate and thickness swelling rate test,The effects of different additions of modified clay on the properties of wood-based foam composites were investigated,and the effects of polypropylene azodimethylamide Extrusion mechanism of hot pressing was revealed.The results show that SEM observation shows that the cell distribution is more and more uniform in the fracture surface of the specimen with mRPC addition of 5wt%at 100X,mRPC appears in the cell gap,wrapped up by PP,and the adhesion was maximized.Mechanical properties,porosity,shrinkage,water absorption rate and thickness swelling rate test showed that with 5wt%mRPC,performance achieves optimal:flexural strength was 27.53MPa,flexural modulus being 2112.04MPa,tensile strength being 19.95MPa,the impact strength being 6.30KJ·m-2;The absolute density of volume value reached 70.75cm3;the porosity was 21.39%;shrinkage rate reached 1.17%;water absorption rate increases most significantly;the balance of water absorption rate reached 9.28%;thickness expansion rate decreased by 25%.It showed that mRPC can optimize mechanical properties of foaming wood-based composites,and improve the hygroscopic properties,and expand the application field of materials.(5)RPC/polystyrene(PS)/nanometer cellulose crystals(CNCs)were prepared by electrospinning.The effects of the coating materials RPC/PS/CNCs on the preparation and properties of the polystyrene/nanometer cellulose crystals were studied.The effects of different additions of RPC on the properties of the composite · films were investigated by SEM,mechanical property test,contact angle test and TGA.The effect of the red clay on the properties of the composite films was revealed.The results show that SEM observation shows that the smoothness of the composite film is smooth when the amount of RPC is 4wt%,and the mechanical properties show that when the content of RPC is 3wt%,the tensile strength of the composite film was 0.51 MPa,increasing by 45.72%,to achieve the best.The contact angle test showed that the addition of 3wt%RPC reduced the hydrophobicity of the composite film,and the contact angle increased to 149°,reaching the maximum value.The thermal stability test showed that the RPC/PS/CNCs composite film has a two-stage thermal decomposition method.When the amount of RPC is 4wt%,the maximum pyrolysis temperature reaches 449.5 ?,and the pyrolysis temperature begins to decrease with the increase of the addition amount.It is shown that RPC effectively enhances the mechanical properties,hydrophobicity and thermal stability of composite films,and makes the development of wood-based composites more versatile.