高效液相色谱法测定乙烯-醋酸乙烯酯共聚物(EVA)胶膜中醋酸/醋酸根含量的不确定度评定

Evaluation of Uncertainty for Determination of Acetic Acid/Acetate in Photovoltaic Cells Packaging Material EVA

对液相色谱法测定光伏电池封装材料乙烯-醋酸乙烯酯共聚物(EVA)中的醋酸/醋酸根(HAc/Ac^(-))含量的不确定度进行评定。以去离子水超声溶解EVA中HAc/Ac^(-),pH值为2.5~3.0的磷酸盐缓冲溶液作为流动相,采用反相液相色谱法、紫外检测器检测,以外标法定量。实验中不确定度分量来源于样品重复性测试、样品称量、样品配制、标准曲线计算样品含量。结果表明,当称样量为0.5~1.0 g时,HAc/Ac^(-)含量(以醋酸钠,NaAc计)的测量结果为(128±3)g/g,k=2。不确定度最大来源为标准曲线拟合。

The uncertainty of determination of acetic acid/acetate(HAc/Ac^(-))content in ethylene-vinyl acetate copolymer(EVA)by liquid chromatography(HPLC)was evaluated.The acetic acid/acetate in EVA was ultrasonically dissolved in deionized water,and the phosphate buffer solution with pH of 2.5~3.0 was used as the mobile phase.Reversed-phase liquid chromatography(RP-HPLC)and ultraviolet detector(DAD)were used,and external standard method was used for quantification.The uncertainty components in the experiment were derived from sample repeatability test,sample weighing,sample solution preparation and the work curve fitting.The results showed that when the sample weight was 0.5~1.0 g,the content of acetic acid and acetate(measured by sodium acetate,NaAc)was(128±3)μg/g,k=2.The maximum source of uncertainty was work curve fitting.