Novel High-Efficiency Casein-Based P–N-Containing Flame Retardants with Multiple Reactive Groups for Cotton Fabrics

Abstract

Novel, high-efficiency, and halogen-free flame retardants with reactive groups, casein-based FRs, were synthesized based on a casein hydrolysis solution for cotton fabrics. After treated by the casein-based FRs, cotton fabrics exhibited high-efficiency flame retardancy; the limiting oxygen index (LOI) of treated cotton fabric increased to 39.5%. Compared with other nature flame retardants, the novel flame retardants could impart durable flame retardancy to cotton fabrics. The LOI value could sustain at 26.7% after 40 laundering cycles (LCs). Cone calorimetry and vertical burning test confirmed that the cotton fabrics treated by the casein-based FRs achieved markedly enhanced flame retardancy. X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared (FTIR) indicated that the casein-based FRs were grafted on cellulose by P­(O)–O–C and C­(O)–O–C bonds. Scanning electron microscopy (SEM) revealed that the modification was facile. Thermogravimetry (TG), energy-dispersive X-ray (EDX), TG-FTIR and SEM revealed that the casein-based FRs played an important role in condensed phase, together with the flame retardant behavior in gaseous phase. The casein-based FRs mainly prevented the formation of levoglucosan by phosphorylation of cellulose and catalyzed the dehydration of cellulose. The tensile strength and whiteness of cotton fabrics treated by the casein-based FRs were substantially retained.

Casein/Apricot Filler in the Production of Flame-Retardant Polyurethane Composites

“…One of the halogen-free, bio-based flame retardants is casein, which is a group of related phosphoproteins described with the chemical composition C 81 H 125 N 22 O 39 P. The high content of phosphorus and nitrogen favors the use of casein as a flame retardant for polymer materials. Its effectiveness has been confirmed so far on cotton and polyester fabrics and poly(lactic acid) composites [50][51][52]. The structure of casein is shown in Figure 1.…”

“…The high content of phosphorus and nitrogen favors the use of casein as a flame retardant for polymer materials. Its effectiveness has been confirmed so far on cotton and polyester fabrics and poly(lactic acid) composites [50][51][52]. The structure of casein is shown in Figure 1.…”

“…Figure 11 shows the XRD patterns of apricot filler and casein/apricot filler. In both cases, an intense peak occurs at 2θ = 16-25 • , which corresponds to the diffractions of amorphous cellulose I and amorphous cellulose II [49,50]. For the PUR_REF, wide diffraction from 15-25 • with a maximum peak appeared at approximately 20 • .…”

One‐step treated wood by using natural source phytic acid and uracil for enhanced mechanical properties and flame retardancy

“…XPS curves of C1s and O1s of the char of FR wood are shown in Figure 10(B, C). In the C1s spectrum, by curve fitting treatment, three characteristic peaks at 284.6, 286.0, and 288.2 eV were emerged, which were corresponding to CC/CH/CC, CO/CN and CO bonding respectively 39,40 . As shown in O1s spectrum, the peak at 530.8 eV was assigned to CO in the carbonyl group, the peak at 531.9 eV was assigned to PO in phosphate group, and the peak at 533.1 eV was assigned to the O in COC and POC groups 39,41 .…”

A Comparative Thermal Analysis of Fire-Off Treated Cotton, Polyester and Co/Pet Fabrics

“…Effective FR properties were achieved with increased LOI values (from 18.2 to 52.9) and decreased total heat release (THR) and effective heat combustion (EHC) values. In another innovative study [33], casein-based, P-N containing FRs with -COO − NH4 + and -P=O(O − NH4 + )2 reactive groups, were synthesized based on a casein hydrolysis solution for cotton fabrics. Cotton fabrics, after the treatment, exhibited highly efficient flame retardancy by achieving 39.5% LOI value.…”