Spectra epoxy resin

Epoxy-dlol Adduct. The epoxy-diol adducts were prepared using standard techniques ( 1 ) by heating a mixture of two moles of diol with one mole of epoxy resin at 130-140°C for 8 hours using 1% N,N-dimethylethanolamine as catalyst. Epoxy-diol adducts prepared in this manner showed the absence of epoxy absorption in the infrared spectrum. 

R Original IR spectrum of epoxy resin. b TD Theynal degradation. 

Oxidation studies have been made for cured epoxy resins and the relative stability of the functional groups was established by following the changes in the absorbance ratios of bands associated with the particular functional group 231>. Hence the most unstable groups can be determined easily and their reactions separated from the more stable units. The irreversible 232) and reversible 2331 effects of moisture on epoxy resin systems have also been studied by FT-IR using the difference spectrum method 234). (Fig. 20) shows the interaction spectra obtained after three cycles of water sorption and redrying. The reversible nature of the interactions are clearly demonstrated. 

On comparing the spectrum of the epoxy resin in Fig. 4a with that obtained after reaction with APS dried at 25°C (Fig. 4b), one can see the disappearance of the epoxide peak at 912 cm and the appearance of a strong band at 3500 cm-1 due to —OH groups, as expected from the above reaction. However, after reaction for the same duration with APS dried at 170°C, the disappearance of the epoxide peak at 912 cm"1 and the appearance of the hydroxyl band at 3500 cm 1 are both less significant. The ratio of peak intensities, 912/3500 cm, remains high, indicating inhibition of the amine-epoxide reaction when APS is dried at 170°C. 

The interaction between these films and bulk epoxy resin was assessed by immersing an aluminum mirror coated with an air-dried primer film in a Petri dish filled with the epoxy resin, heating the dish in an oven at 100°C for 1 h, allowing the dish to cool overnight, and then extracting any unreacted material from the surface of the mirror by MEK extraction. Figure 6A is the reflection spectrum of a relatively thick film (ca. 3 / n) of neat DGEBA resin (cast onto polished aluminum from a 3% solution in toluene), and Fig. 6B shows the RAIR spectrum obtained from the mirror that was primed, heated in resin, and extracted. The... 

We have repeated this work to demonstrate the use of the dual-cell FTMS to distinguish isomers in a mixture. Figure 14a shows an electron impact spectrum of the epoxy resin extract introduced via the direct insertion probe. Figure 14b shows the 50 eV CAD... 

Spectra.—The infrared spectrum was recorded with the material sublimed on to cold potassium bromide windows sealed to a gas-tight glass cell with an epoxy resin. The deposit could not be sublimed from the windows without some attack on the bromide and thus it is possible that spurious peaks may be present in the spectrum. The observed peaks are 631vs, 680w, 725vw, and 1308w cm.. ... 

While proton nmr is satisfactory for determinations on low and medium EEW epoxy resins, the method loses accuracy as the EEW increases. As shown in Figure 1, the proton nmr spectrum of DER 332LC (EEW=175) has sharp multiplets and integration of the relative areas is straightforward. But, as the spectrum of EPON 1004 (EEW 950) shows, when the EEW increases, the multiplets broaden due to overlap with the lines of the aliphatic protons in the bridging groups of the oligomers. 

Figure 3.27. The FT-Raman spectrum of the TGDDM epoxy resin MY721. The prominent bands may be contrasted with those from the MIR (Figure 3.16) reflecting the different selection rules for the two vibrational spectroscopic techniques (de Bakker et al, 1993a).

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