Research On Preparation And Properties Of Rare Earth Fluorescent Bamboo Plastic Composites

Bamboo powder, strontium aluminate phosphor, high density polyethylene (HDPE) and coupling agent were used to produce rare earth fluorescent bamboo plastic composite by means of high-speed mixing, banburying and injection molding in this paper. It had combined the advantages of bamboo powder, aluminate long afterglow luminescent material and high density polyethylene, so it had rosy development and application prospect. The developments and application of rare earth fluorescent bamboo plastic composite will not only ease the situation of insufficient forest resources and wood, which is very expensive, but also promote the developments and application of rare earth resources, and adding the luminescence property of bamboo plastic composite. Meanwhile, the problems of the recycling of wasted materials like polymers and bamboo powder will be solved. This paper, This paper firstly screen the better kind and content of coupling agent, the content and particle size of phosphor to prepare a better comprehensive properties of rare earth fluorescent bamboo plastic composite. Then used hydrogen silicone oil modified bamboo powder and phosphor to improve the water resistance of the composite, in order to enlarge its application scope. It would provide the development and application basis of rare earth fluorescent bamboo plastic composite.The effects of three kinds of coupling agents (MAPE, YB-510, KH-510) on the properties of composites were firstly discussed in this paper. Through a variety of instrument analysis indicated that three kinds of coupling agents could all not only improve the dispersibility of bamboo powder and phosphor, the shear thinning effect, and the wettability between fillers and matrix, but also strengthened the interface bonding of composite and decreased the agglomeration. MAPE was the best one among three coupling agents. By analysing the emission spectrum, mechanical property and FESEM of composites with 2%,4%,6%,8% MAPE and observing the chemical structure of composites by FT-IR, results showed that the combination property of composites with 6% MAPE was the best with better properties in the dispersibility of bamboo powder and phosphor in matrix, fewer chances of damage and extinction of phosphor, better interface bonding of composites and less side reaction. On the surface of bamboo powder and phosphor where free hydroxyl groups and anhydride groupsesterification reaction happened and hydrogen bonds were formed, MAPE played a part in connecting two different polar materials.Secondly, the effects of the contents and particle size of strontium aluminate phosphor in rare earth fluorescent bamboo plastic composite were investigated. By adding different contents of phosphor, using analytical instruments to characterize the properties of the composites, and using FESEM to observe the tensile fracture microstructure of composites. The results showed that the combination properties of composites was better when the content of strontium aluminate phosphor was 13.7%, it has a better comprehensive performance, better thermal stability, higher luminous efficiency, better mechanical properties, the dispersibility of phosphor in matrix was better, the agglomeration was less and the utilization of phosphor was high. The study on the particle size of strontium aluminate phosphor showed that the relative luminous intensity increased with the decrease of the particle size of phosphor; the luminescence property, bending strength, bending modulus, tensile strength and impact strength of rare earth fluorescent bamboo plastic composites first increased and then decreased. The composites with 1500 mesh phosphor had relatively stronger interface bonding function and its fillers and matrix had better wettability, which had better mechanical property and dynamic rheology property; FESEM showed that the smaller the size of phosphor particle was, the better the interface bonding of composites will be, but the size of phosphor particle was too small that would lead to increasing agglomeration, which would result in worse interface bonding; The thermogravimetric (TG) and derivative thermogravimetric(DTG) curves of rare earth fluorescent bamboo plastic composites indicated that with 1500 mesh phosphor had better thermal stability, so the combination properties of composite with 1500 mesh phosphor was relatively better.Bamboo powder and phosphor modified hydrogen silicone oil that were used to change their characters from hydrophilism to hydrophobicity, In order to improve the water resistence of rare earth fluorescent bamboo plastic composite. The contact angle analysis showed that unmodified composite surface hydrophilic, modified composite surface hydrophobic; Water absorption and thickness expansion rate of water absorbing analysis showed that the water absorption and thickness expansion rate of water absorbing of composite increased with soaking time increased and finally stabilized, the water absorption and thickness expansion rate of water absorbing of modified composite was more smaller; Emission spectra showed that the relative luminous intensity peak of modified composites was 63% higher than the relative luminous intensity peak of unmodified composites before soaked in water, the relative luminous intensity of them were decreased with increasing soak time, the relative luminous intensity of unmodified composite were decreased much more rapidly:Mechanical properties showed that the mechanical properties of modified composites were superior to unmodified composites before soaked in water, with increasing immersion time, the flexural strength, flexural modulus and tensile strength of composites decreased and then stabilized, the impact strength of composites increased at first then decreased, finally stabilized, compared to the unmodified composite, the bending strength, flexural modulus and tensile strength decreasing rate of the modified composite were more small, while the decreasing rate of the impact strength was large, but stabilized value was bigger than the stabilized impact strength of unmodified composite; Field emission scanning electron microscopy showed that strontium aluminate phosphors and bamboo powder dispersed very well in the modified composite, reunion reduced, the interfacial adhesion strength improved in the modified composite; Infrared spectroscopy showed:the composites were modified by hydrogen silicone oil, the number of free hydroxyl groups was decreased, hydroxyl absorption peak shifted to lower wave number, methyl characteristic absorption peak appeared in 1387.75 cm-1, it indicated that hydrogen silicone oil and the hydroxyl of bamboo fiber and strontium aluminate phosphors surface occurred chemical reaction, it formed a hydrophobic coating layer.