Chemical and micro-structural changes in glass-like carbon during high temperature heat treatment

Abstract

A glass-like carbon was fabricated using furan resin. The influence of heat treatment temperature during fabrication process on the chemical and micro-structural changes was studied by various analytical and spectroscopic methods including TGA, FT-IR, CHN, TEM and XRD. The chemical resistance properties of the fabricated glasslike carbon were also investigated. It has been found that the heat-treated samples at higher temperature up to 2600 o C in N 2 atmosphere had little weight loss, small amounts of functional groups, and high carbon content. The fabricated glass-like carbons upon heat treatment at 2600 o C showed an amorphous stage without any grain growth and/or reconstruction of structure. The glass-like carbon had much better chemical resistance than the artificial graphite, and exhibited a high chemical resistance due to its low surface areas, minimum impurities, and low graphite crystallites.

Comparison of Structural Features of Humins Formed Catalytically from Glucose, Fructose, and 5-Hydroxymethylfurfuraldehyde

“…A comparison of the humins spectra to the spectrum of HMF in Figure 6 shows that these peaks arise from the furan ring of HMF. 12,39 This is clear for the 1525 cm −1 feature, but in the 750 to 850 cm −1 range the bands in the humins are shifted relative to HMF. Nonetheless, we believe these peaks do arise from furan rings; DFT frequency calculations for products of the condensation of Scheme 3.…”

“…The first group, indicated in the figure by dashed gray lines, includes two peaks in the 750 to 850 cm –1 range, a peak at 1030 cm –1 , and a peak at 1525 cm –1 . A comparison of the humins spectra to the spectrum of HMF in Figure shows that these peaks arise from the furan ring of HMF. , This is clear for the 1525 cm –1 feature, but in the 750 to 850 cm –1 range the bands in the humins are shifted relative to HMF. Nonetheless, we believe these peaks do arise from furan rings; DFT frequency calculations for products of the condensation of DHH with HMF indicate vibrational modes of the furan ring in this range that do not appear at the same frequencies as the corresponding modes in HMF.…”

“…1625 and 1710 cm –1 indicated by solid gray lines in the figure, are prominent in the glucose and fructose humins, while they cannot be distinguished in the HMF humins. The location of these two peaks is characteristic of a carbonyl group conjugated to an alkene group . They might also be attributed to a conjugated diene structure such as that proposed to exist in polymers of furfuryl alcohol, , but in that case we would expect them to be most evident in the humins formed from HMF.…”

“…The location of these two peaks is characteristic of a carbonyl group conjugated to an alkene group. 39 They might also be attributed to a conjugated diene structure such as that proposed to exist in polymers of furfuryl alcohol, 40,41 but in that case we would expect them to be most evident in the humins formed from HMF. The intensity of these two peaks helps to answer the question of whether humins are formed by the direct polymerization of glucose and fructose, or whether glucose and fructose first be converted to DHH via HMF before humins can form.…”

Study on Preparation and Property of Woodceramics

“…But studies on the impregnating resin just involve liquid and solid phenolic resin [7][8][9], and epoxy resin [10]. Some results show that furane resin can be transformed into glassy carbon after carbonization with a high carbon yield ratio [11]. Furane resin is a kind of synthetic resin made from furfural or furfuryl alcohol which has furane-ring structure.…”