Sodium alginate oxide assembly layered double hydroxide and its structure-activity relationship to anti-fogging properties and flame retardancy of leather

The small molecular volatilized during the leather fogging process will pollute the air environment inside the car and make leather products flammable. In this paper, layered double hydroxide (LDH) was modified by different dosage of oxidized sodium alginate (OSA) via exfoliation-reassembly, and its structure were investigated by XRD and TEM. Then modified Zanthoxylum Bungeanum Maxim Seed Oil/ OSA modified LDH (MZBMSO/OSA-LDH) were obtained by introducing OSA modified LDH (OSA-LDH) into modified Zanthoxylum Bungeanum Maxim Seed Oil (MZBMSO), and used MZBMSO/OSA-LDH in leather fatliquoring process. The effect of the introduction of OSA-LDH on the anti-fogging and flame retardancy of leather was investigated. Compared to the MZBMSO treated leather, MZBMSO/OSA-LDH-0.2 treated leather exhibited remarkable improvement on fogging value of the leather, which was decreased by 45%. Furthermore, the leather treated by MZBMSO/OSA-LDH-0.4 has reduction of length of charring and smoke density around 36.1% and 37.5%, respectively. A potential interaction mechanism demonstrates that under the influence of OSA-LDH, an organic-inorganic interpenetrating network structure formed by leather collagen fibers-fatliquor molecule-LDH layer, which utilized to the steric hindrance and adsorption effect to hinder small molecule migration inside the leather fibers, thereby suppressing the fogging of the leather.