Structures, Properties and Potential Applications of Corncob Residue Modified by Carboxymethylation

Abstract

In this study, corncob residue (CR) valorization was simply and efficiently realized via carboxymethylation, and its enhanced performance as fillers in urea-formaldehyde (UF) resin was investigated. The structures of corncob residue and carboxymethylated derivative were analyzed by nuclear magnetic resonance (NMR), Fourier-transform infrared spectroscopy (FTIR), and Raman techniques, respectively. The thermal stability, morphology, viscosity control, and adhesive strength were then investigated to evaluate its performance as fillers in UF resin composite. Similar to commercial flour, carboxymethylated CR could effectively disperse in UF resin. It also exhibited a better initial viscosity control between 30 and 50 °C. The adhesive test analysis showed that the shear strength of resin with carboxymethylated CR addition could reach 1.04 MPa, which was comparable to flour (0.99 MPa) and significantly higher than raw CR (0.45 MPa). Moreover, a low formaldehyde emission was observed.

Cross-Linked Carboxymethylcellulose Adsorbtion Membranes from Ziziphus lotus for the Removal of Organic Dye Pollutants

“…phase of the cellulose, so it demonstrate that the ordered structure of the cellulose has been disrupted during the carboxymethylation of the cellulose, similar to what Gao et al [47]. Mazuki et al [48] suggested that during the etherification of the cellulose with MAC the hydrogen bonds of that join the cellulose chains are cleaved.…”

“…However, the XRD spectra of the PA-CMC and α-CMC presented a single broad band at 2θ~18 • and 2θ = 20 • , respectively, as it can be seen in Figure 1. This band is associated with the amorphous phase of the cellulose, so it demonstrate that the ordered structure of the cellulose has been disrupted during the carboxymethylation of the cellulose, similar to what Gao et al [47]. Mazuki et al [48] suggested that during the etherification of the cellulose with MAC the hydrogen bonds of that join the cellulose chains are cleaved.…”

“…To confirm that the carboxymethylation reaction of the alkaline and α-cellulose has occurred, the obtained PA-CMC and α-CMC were subjected to a XRD analyses. Commonly, the cellulose presents characteristics peaks at 2θ = 15.7 • , 22.1 • and 34.5 • , which are associated to the (101), (002), and (400) lattice planes of cellulose [47]. However, the XRD spectra of the PA-CMC and α-CMC presented a single broad band at 2θ~18 • and 2θ = 20 • , respectively, as it can be seen in Figure 1.…”

“…The bands observed at 3340 and 2900 cm −1 correspond to the stretching frequency of hydroxyl groups in cellulose and to the stretching vibration of the C-H bond [47]. The bands observed at 1450, 1372 and 1317 cm −1 are attributed to the crystalline structure of the cellulose, while the band observed at 1030 cm −1 is characteristic of the cellulose [49].…”

Recent developments in lignin modification and its application in lignin‐based green composites: A review

“…[ 103 ] Lignin has recently been employed as an adhesive alternative to fiberboard panels, combined with other biopolymers such as chitosan, and as the only bioderived element by exploiting the lignin/built‐in biopolymer's compatibility with wood fiber. [ 104 ] Lignin can improve interfacial adhesion between wood fibers and the polymer matrix when included in the fiber of particle composites. [ 24 ] As a compatibilizer, kraft lignin, a wood flour/PP composite, is used, and mechanical testing is used to study the effect of lignin levels on compatibilization.…”