Al@SiO2@Al2O3双层复合材料的可控合成及其耐腐蚀与力学性能

为了有效提高铝颜料的耐腐蚀与力学性能,通过一种温和有效的Sol-Gel法,首先在铝颜料表面包覆一层SiO2,再通过异丙醇铝水解产生A12O3,从而制备了 Al@ SiO2@ Al2O3的双层复合材料。利用扫描电镜、EDS谱、红外光谱、X射线衍射等分析手段对包覆前后的铝颜料的微观形貌及包覆层成分进行分析和表征;通过析氢试验来考察样品的耐腐蚀性能;并将双层包覆的铝颜料添加到PVC树脂中,研究铝颜料对PVC树脂的拉伸性能和硬度的影响。结果表明:表面包覆质量分数约10%的SiO2和4%的A12O3,室温条件下,反应时间为4 h,Al2O3能够在铝颜料表面形成表面光滑、致密的包覆层,在浓度为0.5 mol/L的盐酸中,缓蚀效率达84.6%;添加0.10%(质量分数,下同)铝颜料,PVC树脂的拉伸强度提高45.77%,断裂伸长率提高46.55%,硬度提高27.05%;添加0.15%铝颜料时PVC树脂的光泽度有89.7Gs.

Controllable Synthesis of Al@SiO2@Al2O3 Double-Layer Composite and Evaluation of Its Corrosion Resistance and Mechanical Properties

In order to effectively improve the corrosion resistance and mechanical properties of aluminum pigments, a mild and effective sol-gel method was used to prepare the Al@ SiO2@ A12O3 double-layer composite by coating SiO2 layer on aluminum pigments and producing A12O3 from the hydrolysis of aluminum isopropoxide. Scanning electron microscope, energy dispersive spectrometer, infrared spectroscopy, and X-ray diffractometer were employed to analyze and characterize the microstructure and coating composition of aluminum pigments before and after coating treatment. In addition, the corrosion resistance of the samples was examined by hydrogen evolution experiments. Double-coated aluminum pigments were added to PVC resin to study the effect of aluminum pigments on the tensile properties and hardness of PVC resin. Results showed that the mass fractions of SiO2 and A12O3 in surface coating were about 10% and 4%, respectively. The A12O3 could form a smooth and dense surface on the surface of aluminum pigments for the reaction time of 4 h at room temperature. The corrosion inhibition efficiency of the coating was 84.6% in 0.5 mol/L hydrochloric acid. With adding 0.10%(mass fraction, hereafter) aluminum pigments, the tensile strength of PVC resin was increased by 45.77%, and the elongation at break was increased by 45.77% as well as the hardness was improved by 27.05%. When the content of aluminum pigment was 0.15%, the gloss of obtained PVC resin was 89.7 Gs.