| Nano-particles have high surface activity and a great inclination to agglomerate due to the lack of coordinate atoms on the surfaces.Dispersion of nano-particles and the interfacial compatibility between nano-particles and polymer are key questions and research hotspots on preparing high performance nano-composite materials.Surface modification of nano-particles is a simple and effective way to ameliorate the dispersion of nano-particles and the interfacial compatibility between nano-particles and polymer.In this thesis,some organic compounds with certain functional groups were used for modifying nano-calcium carbonate and nano- aluminum oxide, which can bring certain functional groups onto surface of those nano-particles. In this way those modified nano-particles and polymer can be linked by chemical bond.Consequently,the interface between nano-particles and polymer becomes firm remarkably.Main work as follow:1,Nano-calcium carbonate is modified by benzenesulfonic acid 4-ethenyl- sodium salt(SSS)which brings vinyl onto surface of nano-calcium carbonate.It is certain that nano-calcium carbonate is absorbed by SSS in physical process by analyzing infrared spectrum,settlement volume.The optimal experimental condition is that:W(SSS):W(CaCO3)=3:100,reaction temperature =80℃,PH= 6～7,reaction time =2 hours.2,Nano-calcium carbonate is modified by 4-Aminobenzoic acid which brings amido onto the surface of nano-calcium carbonate.It is likely that nano-calcium carbonate is absorbed by 4-Aminobenzoic acid in physical process by analyzing infrared spectrum and settlement volume.The optimal experimental condition is that:W(4-Aminobenzoic acid):W(CaCO3)=4:100,reaction temperature =70℃,reaction time =2 hours.3,There are vinyls on the surface of nano-calcium carbonate which was modified by diallyl dimethyl ammonium chloride(DMDAAC).It is certain that nano-calcium carbonate is absorbed by DMDAAC by analyzing X-ray photoelectron spectroscopy(XPS)and settlement volume.The optimal experimental condition is that:W(DMDAAC):W(CaCO3)=7:100,reaction temperature =85℃,reaction time =2 hours.4,Conjugated linoleic acid(CLA)is used for modifying nano-calcium carbonate.By analyzing XPS,Transmission electron microscopy(TEM)and weight loss,it is certain that nano-calcium carbonate and CLA are integrated by chemical bond and conjugated double bond is brought onto the surface of nano-calcium carbonate.The optimal experimental condition is that:W(CCA): W(CaCO3)=5:100,reaction temperature =75℃,reaction time = 1 hours.5,Amino propyltriethoxysilane(KH550)is used for modifying nano-aluminum oxide.By analyzing infrared spectrum,XPS and weight loss, it is certain that nano-aluminum oxide and KH550 are integrated by chemical bond and amido is brought onto the surface of nano-calcium carbonate.By analyzing settlement volume,the optimal experimental condition is obtained: W(KH550):W(Al2O3)=5:100,reaction temperature =80℃,reaction time =4 hours.6,In application research,it is found that the coating of waterborne polyurethane with modified nano-aluminum oxide has a higher hardness than the coating of pure waterborne polyurethane.Compared to the coating of waterborne polyurethane with unmodified nano-aluminum oxide,the coating of waterborne polyurethane with modified nano-aluminum oxide has a higher hardness too.At the same time,compared to the coating of waterborne polyurethane with unmodified nano-aluminum oxide,the coating of waterborne polyurethane with modified nano-aluminum oxide has a greater enhance on abradability.In the test of shear strength of epoxy resin,the epoxy resin with modified nano-aluminum oxide has higher shear strength than the epoxy resin with unmodified nano-aluminum oxide. |
