"Identification method of natural rubber, isoprene rubber and natural rubber/isoprene rubber blend"

Abstract

Six kinds of natural rubbers and two kinds of isoprene rubbers were extracted with acetone as the solvent, and the selection of the internal standard for quantitative analysis of raw rubbers of natural rubber and isoprene rubber and vulcanizates of natural rubber, isoprene rubber and natural rubber/isoprene rubber blend was based on the diffe-rence in the composition of acetone extract concentrate of natural rubber and isoprene rubber. In addition, acetone extract concentrate was analyzed by internal standard method, and the identification method of natural rubber, isoprene rubber and natural rubber/isoprene rubber blend was established. Finally, the method was applied to the identification of the main components of the submitted samples. The results showed that squalane could be used as the internal standard for quantitative analysis of natural rubber, isoprene rubber and natural rubber/isoprene rubber blend. Under the preferred gas chromatography-mass spectrometry quantitative analysis and detection conditions, the blending ratio of natural rubber and isoprene rubber in natural rubber/isoprene rubber blend could be measured by the qualitative analysis of γ-sitosterol and γ-tocotrienol in natural rubber, combined simultaneously with the quantitative analysis of the specific antioxidant in the acetone extract concentrate of vulcanizate by internal standard method, of which the deviation was -5% when the characteristic fragment ion whose mass to charge ratio was 296 was used as the referenced characteristic fragment ion for quantitative analysis. The identification method showed good results in identifying the main components of the submitted samples.