Gamma irradiation effects on polycaprolactone/zinc oxide nanocomposite films

Abstract Polycaprolactone (PCL) to which has been added zinc oxide nanoparticles (ZnO NPs) produces nanocomposites (PCL/ZnO NCs). These nanocomposites can be used in biomedical applications and in the food packaging sector. However, for these materials to be used in these applications, they need to be sterilized. For this, gamma irradiation is the most common method. Thus it is important to evaluate the effects of gamma irradiation on the properties of PCL and PCL/ZnO that have been exposed to gamma irradiation. PCL/ZnO NCs films were obtained by solvent casting and exposed to gamma irradiation at 25 kGy and evaluated by Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) scanning electron microscopy (SEM) and mechanical properties. Mechanical properties and crystallinity showed marginal variations for the irradiated samples. The results obtained demonstrate that gamma irradiation at 25 kGy, did not cause profound changes in nanocomposite properties.

摘要：添加氧化锌纳米颗粒（zinc oxide nanoparticles, ZnO NPs）的聚己内酯（polycaprolactone, PCL）可制备得到纳米复合材料（nanocomposites, NCs，即PCL/ZnO NCs）。该类纳米复合材料可应用于生物医学领域以及食品包装行业。然而，若要将此类材料投入上述应用场景，需先对其进行灭菌处理，而伽马辐照（gamma irradiation）是当前最常用的灭菌方法。因此，评估伽马辐照对经辐照处理的聚己内酯及PCL/ZnO纳米复合材料性能的影响至关重要。本研究通过溶液浇铸法制备PCL/ZnO纳米复合材料薄膜，将其置于25 kGy剂量下进行伽马辐照处理，并采用傅里叶变换红外光谱（Fourier transform infrared spectra, FT-IR）、X射线衍射（X-ray diffraction, XRD）、热重分析（thermogravimetric analysis, TGA）、差示扫描量热法（differential scanning calorimetry, DSC）、扫描电子显微镜（scanning electron microscopy, SEM）以及力学性能测试对其进行表征。结果显示，辐照样品的力学性能与结晶度仅存在微弱变化。本研究所得实验结果表明，25 kGy剂量的伽马辐照不会对纳米复合材料的性能造成显著改变。