Effect of modified hydrotalcites on flame retardancy and physical properties of paper

Abstract

Functionalized layered double hydroxides (LDHs) based on a multi-modifier system composed of itaconic acid (ITA) and titanate coupling agent (NDZ-201) were designed and fabricated in this paper with the aim to develop high-performance fire retardant paper. The structure of LDHs were characterized using Fourier transform infrared spectroscopic analysis, X-ray diffraction analysis, thermogravimetric analysis (TGA), scanning electron microscopic analysis, cone calorimetry, and laser particle size analysis. The results showed that carbonate anions were partially replaced by ITA, whereas the titanate coupling agent was attached to the surfaces of the hydrotalcites. The limiting oxygen index (LOI), TGA curves, total heat release rate (THR), and heat release rate (HRR) indicated that as the addition of hydrotalcites increased, the modified LDHs’ LOI value and thermal stability noticeably increased compared to the unmodified hydrotalcites, and the HRR and THR of the material decreased. When the addition amount was 25%, the LOI of ITA-LDHs was 26.9%. However, the Mg-Al hydrotalcites adversely affected the strength index of flame-retardant paper; the modified hydrotalcites clearly reduced this effect, and the whiteness of paper increased and reached 83%.

Itaconic acid-modified layered double hydroxide/gellan gum nanocomposites for Congo red adsorption

“…3 b. In the thermogram of the LDH, a mass loss (2.7%) was observed between 30 and 235 °C because of the removal of water 30 . Also, a mass loss of about 3.7% occurred between 235 and 580 °C due to decomposition of –OH groups and degradation of the layered structure.…”

“…In the modified sample, the broadband centered at 3473 cm −1 is related to the hydroxyl groups. On the other hand, the bands at 1646 cm −1 and 1431 cm −1 are assigned to the carboxylic ions absorption bands 30 , 31 . The C=C stretching vibration can be observed at 1565 cm −1 .…”

Raman Spectroscopy for Characterization of Hydrotalcite-like Materials Used in Catalytic Reactions

“…Their excellent anion exchange capacity stimulates the use as host-guest materials applied in the pesticide-related field [39]. The improved thermal, mechanical and rheological properties of PNCs containing LDHs significantly enhance the performance on flame retardancy and physical properties of the paper and epoxy resin [40,41]. Low cost plastic films can be produced and used in agricultural area.…”

Eco-friendly flame-retardant Xuan paper via layer-by-layer assembly organic/inorganic composite coating on pulp fiber

“…Inorganic flame retardants are the most widely used in the addition method due to their lower cost, for instance, aluminum hydroxide and magnesium hydroxide (Yang et al 2017;Zhou et al 2020). However, the needed usage levels of these inorganic flame retardants are usually large, which may greatly influence the physical properties of paper (Wang et al 2019). Organic halogen containing and/or phosphorus containing compounds are the effective flame retardants (Chen et al 2018;Fang et al 2019).…”