Preparation And Properties Of Multifunctional PMMA/ZnO Nanocomposites

Nano-ZnO is a versatile material with UV-shielding,antibacterial,photocatalytic and photoluminescence properties.Polymethylmethacrylate（PMMA）shows superior mechanical properties and high transparency to visible light（400⁸00 nm）,which makes it applicable to construction,transportation,advertising and other fields.However,PMMA could not availably block ultraviolet radiation（UV）that is harmful to the human body.In addition PMMA is not provided with antibacterial,photoluminescence or other multifunctional properties.The strategy is to add ZnO into PMMA.Since the high surface energy of ZnO and its poor compatibility with PMMA,ZnO tends to be unevenly distributed in PMMA,resulting in opaque or translucent PMMA/ZnO nanocomposites.The researchers usually employ three methods of solution mixing,surface modification and in-situ polymerization to prepare highly transparent PMMA/ZnO nanocomposites.The solution mixing method requires a large amount of toxic solvents.The surface modification process of ZnO is complicated and time consuming.While in-situ polymerization method is simple and non-toxic（or low-toxic）.In this research,PMMA/ZnO nanocomposites were prepared by modified in-situ polymerization method using MMA as monomer,AIBN as initiator,Zn（Ac）₂·2H₂O as precursor,LiOH·H₂O as catalyst and anhydrous ethanol as solvent.The characterization results of FTIR,XRD,TEM,and UV-Vis show that ZnO dispersed homogeneously in the PMMA matrix,and PMMA/ZnO nanocomposites possess antibacterial,anti-ultraviolet,photoluminescence and high transparency properties.For mass production,one-step in-situ polymerization process was employed to prepare PMMA/ZnO composites,which is simple,environmentally friendly,and economical.The results of FTIR,XRD,TEM,UV-Vis and AFM indicate that PMMA/ZnO nanocomposites with outstanding thermal and optical properties have been successfully prepared.Due to the uniform dispersion of ZnO（3⁵ nm）in the PMMA matrix,the PMMA/ZnO nanocomposites have the advantages of high transparency（>90%）,efficient UV-shielding capacity（>95%）and bright luminescence.Multifunctional PMMA/ZnO nanocomposites have potential applications in the fields of UV-shielding coatings,agricultural films and antibacterial plastics.Based on the PMMA/ZnO nanocomposites and the hydrophobic SiO₂,superhydrophobic PMMA/ZnO/SiO₂coatings were prepared.and applied to a substrate such as PMMA by dip coating method.AFM,SEM,UV-Vis,CA and other characterization results demonstrate that roughness PMMA/ZnO/SiO₂ coating is uniformly dispersed on the surface of the substrate,and the coating has both high transparency and superhydrophobic property.The coating is expected to be used in self-cleaning glass,electronic equipment,automotive transportation and other fields.