Abstract：
The aim of this study was the synthesis of bimetallic nanoparticles based on Fe2O3/TiO2 and its use in the poly(lactic acid) (PLA) films as an oxygen scavenger in extra virgin olive oil (EVOO) packaging. Bimetallic nanocomposites were prepared by two different precipitation methods (precipitation with ammonia and sodium hydroxide). The characteristics of bimetallic nanoparticles precipitated with sodium hydroxide (Na-Ti0.01Fe0.048O0.08) and bimetallic nanoparticles precipitated with ammonia (NH-Ti0.01Fe0.022O0.09) were compared. Relative amounts of elements in bimetallic nanocomposites and their morphological characteristics were determined using field emission scanning electron microscopy coupled with energy-dispersive X-ray spectrometer. Porosity volume and surface area of bimetallic nanoparticles were calculated using adsorption-desorption isotherms and the Brunauer-Emmett-Teller method. The formation/characterization of bimetallic nanoparticles and their location in the matrix of PLA-based nanocomposite film was studied using X-ray diffraction and Fourier transform infrared. In nanocomposite films based on PLA, bimetallic nanoparticles lead to better oxidative stability (peroxide value, p-anisidine index, K232, and K270) of the EVOO and oxygen scavenging during storage compared to free nanoparticles. Mechanical properties of nanocomposite films were improved due to bimetallic nanoparticles, which were better for Na-Ti0.01Fe0.048O0.08. In vitro release modeling of the bimetallic nanoparticles in EVOO proved that Fickian diffusion is the dominant mechanism, and the Peleg model was the best description of the release behavior of nanoparticles.
摘要：
这项研究的目的是基于Fe2O3/TiO2的双金属纳米粒子的合成及其在聚乳酸（PLA）薄膜中作为特级初榨橄榄油（EVOO）包装中的氧清除剂的用途。通过两种不同的沉淀方法(用氨和氢氧化钠沉淀)制备双金属纳米复合材料。比较了用氢氧化钠沉淀的双金属纳米颗粒(Na-Ti0.01Fe0.048O0.08)和用氨沉淀的双金属纳米颗粒(NH-Ti0.01Fe0.022O0.09)的特性。使用场发射扫描电子显微镜和能量色散X射线光谱仪确定双金属纳米复合材料中元素的相对含量及其形态特征。使用吸附-解吸等温线和Brunauer-Emmett-Teller方法计算双金属纳米颗粒的孔隙率和表面积。使用X射线衍射和傅里叶变换红外研究了双金属纳米颗粒的形成/表征及其在PLA基纳米复合膜基质中的位置。在基于PLA的纳米复合膜中，双金属纳米颗粒导致更好的氧化稳定性(过氧化物值，对茴香胺指数，K232和K270）与游离纳米颗粒相比，在储存过程中的EVOO和氧清除。由于双金属纳米粒子的存在,纳米复合薄膜的力学性能得到了改善,其中Na-Ti0.01Fe0.048O0.08更好。EVOO中双金属纳米颗粒的体外释放模型证明了Fickian扩散是主要机制，Peleg模型是纳米粒子释放行为的最佳描述。
