二维红外相关光谱在鉴别不同配方树脂中的应用

采用红外光谱结合二维相关分析技术,对添加不同固化促进剂的环氧树脂进行了快速鉴别研究.结果表明,二者在一维红外光谱图上没有差别,但是在二维红外相关谱图上却存在明显的差异.在对4000-2500cm-1和1600-730cm-1两个区域的同步和异步光谱进行研究后发现,配方B有甲基自动峰的出现,而配方A则无；配方A中基团变化顺序为：-CH3＞-CH2＞苯环C=C,醚C-O-C＞一CH2＞苯环C=C,环氧C-O-C＞苯环C=C,苯环=CH＞苯环C=C,苯环=CH＞叔丁基C-C；配方B中基团变化顺序为：环氧C-O-C＞苯环C=C,醚C-O-C＞苯环C=C＞叔丁基C-C,-CH3＞苯环C=C＞叔丁基C-C.研究得到两种树脂体系中-OH、苯环C=C、-CH2、-CH3、叔丁基C-C、醚C-O-C、环氧C-O-C、苯环=CH等基团光谱强度的变化相关性.因此,二维相关红外光谱可以用于揭示树脂反应过程中的高分子链段内不同基团的变化规律和相互作用,并用于一维红外谱图无差别的树脂的鉴别.

Application of Generalized Two-Dimensional Infrared Correlation Spectroscopy on Distinguishing Resin Formulation

Abstract A practicable and efficient methoct tor ldentification of different epoxy formuations with different curing accelerator was conducted by Fourier transform infrared spectroscopy（FTIR） combined with two-dimensional correlation spectroscopy （2D） technique. The two resin formulations tested were similar to each other in one-dimensional IR spectra but quite different in 2D-FTIR spectra. An investigation on 2D FTIR synchronous and asynchronous spectra disclosed that in the range of 4000--2500cm-1 and 1600--730cm-1, methyl auto-peak appears in the synchronous spectrum of formulation B,while not in the formulation A; As follows are the intensities variations order of formulation A ：--CH3〉--CH2〉 benzene ring C =C, Ether C--O--C〉--CH2〉 benzene ring C=C,Cyclic C--O--C〉benzene ring C=C,benzene ring =CH〉benzene ring C =C,benzene ring=CH〉Tert-butyl C-C;As follows are the intensities variations order of formulation B.Cyclic C--O--C〉 benzene ring C =C, Ether C--O--C〉 benzene ring C=C〉 Tert-butyl C--C,--CH3 benzene ring C=-C〉Tert-butyl C-C. In addition,The correlation intensities of --OH, benzene ring C =C、--CH2.--CH3. Tert-butyl C--C. Ether C--O--C. Cyclic C--O--C and benzene ring =CH can be obtained. The results proved that 2D correlation spectra could enhance the resolution of infrared spectra and increase the capability of identification,which make it a powerful and new approach to identifying different resins.