Preparation And Properties Of Fe₃O₄/Bamboo Scrimber Composites

Bamboo is prone to mildew and deformation due to its own characteristics,which seriously affects the processing and utilization of bamboo.Adding inorganic nanomaterials is a way to modify bamboo,which can effectively improve the properties of bamboo,and improve the quality and utilization of bamboo products.In this paper,taking the bamboo bundles that have been loosened by bamboo wood as a unit,using the manufacturing process of reconstituted bamboo to explore the influence of heat treatment process and the solubility of the precursor solution on the properties of Fe₃O₄/bamboo scrimber composites.The bamboo bundle unit was heat-treated under saturated steam at 180?for 10 min,20 min,30 min,40 min,and 50 min to explore the effect of heat treatment time on the properties of Fe₃O₄/bamboo scrimber composites.Taking untreated bamboo bundles as raw materials,impregnating iron salt precursor solutions of 0.2 mol/L,0.4mol/L,and 0.6 mol/LFe³⁺to explore the effect of Fe₃O₄ addition on the properties of Fe₃O₄/bamboo scrimber composites1.Fe₃O₄/bamboo bundles were prepared and characterized by normal pressure impregnation technology and in-situ composite method.As the heat treatment time increases,the hemicellulose is degraded in a large amount.The relative content of hemicellulose in the bamboo bundle at 20min and 30 min decreases rapidly,from 10 to 20 min to 8.62%,and from 20 to 30 min.6.35%,the amount of hemicellulose decomposed in 10 to 30 minutes reached 58.1%of the total amount of hemicellulose.In addition to the C and O elements on the surface of Fe₃O₄/bamboo bundles,there is also Fe element.XRD proves that the material is Fe₃O₄.The infrared spectrum shows that the hemicellulose and part of the lignin are degraded during the heat treatment and alkali treatment.As the heat treatment time increases,the EDS mapping analysis shows that the Fe element signal on the surface of the bamboo bundles heat treated for 30 min is stronger.The Fe₃O₄/bamboo bundle prepared by immersing iron salt precursor solutions with different solubility,the amount of Fe₃O₄added increases with the increase of the solubility of the precursor solution.2.The Fe₃O₄/bamboo bundle unit was dipped and hot-pressed to prepare the Fe₃O₄/bamboo scrimber composites by using the bamboo scrimber preparation process,and then characterized.During the hot pressing process,the bamboo bundle unit is squeezed and compacted,and the surface analysis shows that there is a Fe element signal.AFM analysis shows that the Fe₃O₄/bamboo scrimber composites is a multi-phase material including the bamboo bundle unit,metal oxide and phenolic resin.Micro-CT analysis showed that Fe₃O₄ was uniformly distributed inside the bamboo scrimber composites,and the particles were distributed along the direction of the bamboo fiber.The maximum amount of Fe₃O₄ added to the bamboo bundle was 30 min under the heat treatment process.When immersing iron salt precursor solutions with different solubility,the amount of Fe₃O₄ added increases with the increase of the solubility of the precursor solution.3.Refer to the mechanical standard to test the physical properties of Fe₃O₄/bamboo scrimber composites.The elastic modulus,static flexural strength,and tensile strength along the grain of the Fe₃O₄/bamboo scrimber composites prepared from the heat-treated bamboo bundles all decrease with the increase of the heat treatment time.The compressive strengths along the grain and transverse grain first increase and then decrease with the increase of time,reaching larger values in 20 minutes,68.23 MPa and 60.87 MPa,respectively.Compared with the untreated bamboo scrimber,the increase rates are 5.9%and 12.1%,respectively.The water absorption of bamboo scrimber is directly proportional to the loading of Fe₃O₄ nanoparticles,and the size of the water contact angle is inversely proportional to the loading of Fe₃O₄ nanoparticles.The elastic modulus,static flexural strength,along-grain tensile strength of Fe₃O₄/bamboo scrimber composites prepared by dipping bamboo bundles with different iron salt solubility are all reduced compared with bamboo scrimber,and with the increase of iron salt solubility,first increase and then decrease,the larger value at 0.4 mol/L solubility.The compressive strength of the along-grain and transverse-grain is enhanced compared with the untreated bamboo scrimber,with the largest increase of 26.4%and 36.1%respectively.Both the water absorption weight gain rate and the size change increase with the increase of the solubility of the impregnated iron salt.4.In the 30-day infection experiment with Aspergillus niger,the five groups of Fe₃O₄/bamboo scrimber composites prepared by heat-treated bamboo bundles were not infected.The anti-mold performance of Fe₃O₄/bamboo scrimber composites prepared by immersing bamboo bundles with different iron salt solubility increases with the increase of the immersion iron salt solubility.