Synthesis and structural characterization of urea–isobutyraldehyde–formaldehyde resins

Abstract

Urea-isobutyraldehyde-formaldehyde (UIF) resins were synthesized using urea, isobutyraldehyde, and formaldehyde; sulfuric acid was used as a catalyst. The effects of molar ratio of urea/isobutyraldehyde/ formaldehyde (U/I/F) on the properties of resins were investigated, and the structures of the resins were characterized by FTIR, 1 H-NMR, and 13 C-NMR. When U/I/F was 1.0/3.6/2.4, the yield of the resin was 76.5%. The softening point and hydroxyl value were 90°C and 32 mg KOH/g, respectively. The FTIR, 1 H-NMR, and 13 C-NMR results showed that an a-ureidoalkylation reaction occurred between urea and isobutyraldehyde to form a lactam. The UIF resins also contained hydroxyl groups and aldehyde groups; the content of aldehyde groups in the resin increased as the amount of isobutyraldehyde increased.

The effect of TiO2 component on the properties of acrylic and urea-aldehyde resins under accelerated ageing conditions

“…9) showed peaks at 2963 and 2874 cm −1 due to asymmetric and symmetric stretching vibrations, respectively, of C-H bonds in the CH 3 , deformation of geminal methyl groups at C(CH 3 ) 2 at 1218 and 1154 cm −1 are also observed [2,10,11]. The FTIR spectra showed significant photochemical alterations for the aged material.…”

“…It has been extensively applied as additive in polymers and polymer composites due to its potential protective properties for the underlying paint layers [18,19]. Research Table 2: Laropal A81 [9,10].…”

Synthesis, structure, and characterization of glyoxal‐urea‐formaldehyde cocondensed resins

“…One relatively unexplored approach is the use of alternative, nontoxic, nonvolatile aldehydes to produce urea‐based resins for wood adhesive. Up to now, the reported alternative aldehydes are dimethoxyethanal, propionaldehyde, succinaldehyde, glutaraldhyde, and isobutyraldehyde . However, these aldehydes still have problems: either they are toxic to some extent or they are volatile; or they present other problems such as low reactivity, solubility, or high cost.…”

Wood products and green chemistry

“…Resins based on urea-glyoxal for textiles are wellknown (Petersen 1968), but these are low condensation resins not adaptable for wood. Hybrid resins urea-formaldehydeanother aldehyde have been the initial target of several researchers, with good results for plywood (Deng et al 2014b;Zhang et al 2009Zhang et al , 2014. The problem of these is that formaldehyde, although much less, is still there.…”