Cellulose-based fabrics have significant advantages, but their application scenarios are limited due to their flammability. This work used biomass phytic acid and protein decomposition products, ...alkaline amino acids (arginine, lysine, histidine) to prepare alkaline amino acid flame retardants (PALA, PALL, PALH), and they were utilized to endow Lyocell fabrics with flame-retardant and antibacterial properties. When the weight gain was about 16.0 wt%, PALA exhibited better flame-retardant effect, and the limited oxygen index value of PALA-Lyocell reached 47.1 %. In the cone calorimetry test, PALA showed the best flame-retardant efficiency in reducing flame growth index with a 92.0 % decrease in peak heat release rate. The results of thermogravimetric analysis coupled with Fourier Transform Infrared spectroscopy (TG-FTIR) and char residues indicated that the flame-retardant property of alkaline amino acid flame retardants was formed through the combined action of gas and condensed phases. In the antibacterial test, PALA had the highest antibacterial rate against Staphylococcus aureus at 97.2 %. Mechanical property, handle feeling, and whiteness results had indicated that alkaline amino acid based flame retardants had little effect on the physical properties of Lyocell fabrics. This work confirms alkaline amino acid based flame retardants have functions of flame-retardant and antibacterial properties, providing reference for the practical value of biomass in cellulose-based fabrics.
Lyocell fiber is regarded as one of the most representative green fibers, which has higher strength than other regenerated cellulose fibers, but is easily fibrillated when produced. Here, we ...developed a strategy to strengthen lyocell fiber by the strong interaction between the small molecules of biomass and polymeric cellulose chain networks. The green biomass naringin molecules containing phenolic hydroxyl structures are introduced into the solvent (N-methyl morpholine-N-oxide, NMMO) system of producing lyocell fiber, and the rational arrangement of naringin and cellulose molecular chains is precisely controlled through fiber-forming process of dry-jet-wet spinning and wet-drafting. Due to the interaction of strong hydrogen bond between naringin and cellulose molecules, the strength, toughness and Young’s modulus of the obtained composite fibers reached 500.78 ± 33.57 MPa, 28.16 ± 4.65 MJ/m3 and 23.06 ± 1.01 GPa, respectively, which were 86.96 %, 44.86 % and 48.97 % higher than those of pure lyocell fibers. In addition, naringin molecules have two directional (the longitudinal and transverse direction) bonding effects, which not only improves the mechanical performance of the fiber, but also reduces the fibrillation. The simultaneously improvement of mechanical performance and the reduction of fibrillation tendency are unprecedented in related studies, which contributes to the production of better performance lyocell fibers.
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•The green biomass naringin was used to strengthen the regenerated cellulose fiber.•The cellulose fiber had excellent mechanical propertie (500 Mpa), an increase of 87 % compared to pure fiber.•The cellulose fibers had excellent anti-fibrillation property, dyeability, weavability, washability etc.
Cellulose fibers are a class of green fibers that are widely used. But its flammability makes it a very high fire risk. According to inference, glycine and phosphoric acid may have the function of ...binding each other and capturing cellulose pyrolysis fragments. This is of great significance for the exploration of the hypothesis that the oxidation process of cellulose can be regulated by adding catalysts so that the oxidized fibers have high carbon yield and ultra-high flame retardancy. In this study, a compound catalyst was prepared with glycine and phosphoric acid in a particular ratio for the first time, and the chemical structure of lyocell fiber during pre-oxidation was adjusted with a specific step-by-step heating system to prepare flame-retardant fiber. The results of flammability testing showed that the limiting oxygen index (LOI) of the oxidized fibers unexpectedly jumped to 66.4%, more than three times higher than that of lyocell fibers with an LOI of only 18%. The UL-94 grade also directly reached the highest level (V-0). This means that the study produced fibers with excellent flame retardancy with a simple method, which to some extent verified the previous hypothesis. Furthermore, based on the abundant XPS and FT-IR data, a unique mechanism for the synergistic flame retardancy of N and P based on the phosphoramide structure is also proposed. This study provides a new method for broadening the application scope of cellulose-based products in the field of fire risk.
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•Exploring simple and efficient flame-retardant catalysts containing N and P.•Controlling cellulose pyrolysis using particular pre-oxidation processes.•Formation of flame-retardant structures related to phosphamides.•Excellent flame-retardant effect and its application.
•NMMO-based CB dispersion is prepared and characterized.•The properties of dispersion rely on structure and amount of dispersant.•NMMO-based CB dispersion has excellent compatibility with lyocell ...spinning solution.•The properties of dope dyeing fiber are affected by CB content.
NMMO-based carbon black (CB) dispersion was prepared and its properties as well as its compatibility with lyocell spinning solution were further investigated. Modified lignosulfonate (SP) was verified to be the preeminent dispersant for the preparation of NMMO-based CB dispersion with mass ratio of SP to CB 20% and water to NMMO 13%. The compatibility of NMMO-based CB dispersion with lyocell spinning solution had close relation with dispersant structure and CB content. Mass ratio of CB to cellulose affects the mechanical properties, color strength and crystallinity of lyocell fiber. 0.5% CB increased the breaking strength and elongation of lyocell fiber, whiles breaking strength and elongation of the lyocell fiber were reduced slightly when 2.0% CB was used. The dope dyed fiber showed excellent rubbing and washing fastness as well as migration resistance to water, ethanol and acetone.
Lyocell fiber has emerged as an important class of regenerated cellulose that is produced based on the N-methyl morpholine-N-oxide (NMMO) dissolution method, and it has unique properties compared to ...viscose fiber. The NMMO technology provides a simple, resource-conserving, and environmentally friendly method for producing regenerated cellulose fiber. In this paper, the manufacturing process, environmental impact, and product quality of lyocell fiber are reviewed and compared with those of the conventional viscose fiber.
•Flame-retardant Lyocell fabrics (PAMA13–100) were prepared using maltitol-modified phytic acid.•After Pad-Dry-Curing finishing, PAMA13–100 exhibited nearly 300 % improvement in mechanical ...performance compared with PA-100.•The limiting oxygen index of PAMA13–100 reached 31.9 %, with a 50 % reduction in peak heat release rate.
The pad-dry-curing process involves padding with finishing liquid, pre-drying, and high-temperature baking. It is widely used in the dyeing and finishing field. For the field of flame-retardant finishing of fabrics, the use of phytic acid (PA) as a raw material can be highly effective. However, the extreme acidity of PA can cause damage to cellulose-based fabrics under high-temperature conditions. The development of PAMA, a compound formed by reacting PA with maltitol, can effectively alleviate the damage of PA to fabrics at high temperatures. PAMA not only exhibits excellent flame-retardant properties by slowing down flame propagation but also helps mitigate the acidic damage to Lyocell fabrics during the pad-dry-curing process, including an increase in the limiting oxygen index (31.9 %), a reduction in peak heat release rate (55 %), and a substantial increase in breaking force retention compared with those of the sample using pure PA as a flame retardant (300 %). Overall, this research presents a promising approach to the development of environmentally friendly flame retardants for textiles, highlighting the importance of balancing effectiveness with fabrics.
•An eco-friendly coating (APP-LA) was prepared based on ammonium polyphosphate (APP) and tyramine (LA).•The APP-LA treated lyocell showed improved flame retardancy.•The possible flame retardant ...mechanism of APP-LA was proposed.
Low-carbon emissions are a sustainable development approach, among which lyocell is a renewable and zero carbon biodegradable cellulose fiber. The flammability of lyocell fabric poses a threat to people's lives and property. In response to this issue, a bio-based flame retardant, tyramine polyphosphate (APP-LA), was synthesized and applied to the treatment of lyocell fabrics. The synthesis of APP-LA adopted an eco-friendly and organic solvent-free method. In the combustion test, the limiting oxygen index of APP-LA treated lyocell fabrics increased to 35.8% compared to control lyocell (18.5%), and the damage length was only 6.7 cm. Meanwhile, the peak heat release rate and total heat release decreased by 92.9% and 58.7% respectively, compared to the control lyocell. Besides, the P-containing compounds generated by APP-LA accelerated the decomposition of the matrix to produce a dense char layer. The fewer flammable volatiles and more non-flammable gases were released. This work provided a low-cost and eco-friendly strategy for the simple preparation of commercial flame-retardant lyocell fabrics.
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•Microbial pigment was used for color construction of lyocell for the first time.•Dyeing effect of lyocell was significantly improved after modification.•The new approach brought ...lyocell fabric with multiple functionalities.•Color and functionality construction exhibited synergistic effect.
As a kind of low-carbon, environmentally friendly and high-quality regenerated cellulose fiber derived from nature plant, the promotion and application of lyocell fiber is attracting much attention. In this paper, for the first time, microbial pigment was applied for color and multifunction construction of lyocell fabric. The size change of the pigment nano-particles during the color construction process was explored to verify the dyeing mechanism of nano-suspension system, and the optimal dyeing condition was obtained. In order to improve the dyeing effect and functionality of fabric, 1,2,3,4-butanetetracarboxylic acid (BTCA) was used to realize the anionic modification of lyocell fabric with high strength retention rate. Under optimal color construction condition, the color depth of the modified fabric was 298.5% higher than that of the unmodified one, and the dyed fabric possessed excellent dyeing uniformity and permeability. Moreover, the crosslinking reaction between BTCA and cellulose macromolecules, as well as the pigment deposition inside the fibers were helpful to the fibrillation prevention function of lyocell fibers. Dyed fabrics inherited the antibacterial and ultraviolet absorption properties of prodigiosins. The bacteriostatic rate against Staphylococcus aureus was above than 98.5%, and the UV protection performance was obviously improved. This technology successfully realized the color and multi-functional construction of the lyocell fabric in one step by natural pigment from microorganism.
Functional materials such as fireproof fabrics or fibers usually destroy mechanical strength due to the introduction of flame retardant. In this work, ionic liquid 1,3-dimethyl imidazolium methyl ...phosphite, one solvent and modifier, was employed to fabricate phosphorylated cellulose. As a cellulose-based derivative, phosphorylated cellulose displayed good compatibility and dispersity in cellulose spinning which was proved by the uniform cellulose spinning dope and compact fiber structure. Owing to the special and similar structure, phosphorylated cellulose interaction with cellulose unit was conducive to enhancing mechanical strength of lyocell fiber. The flame retardant lyocell fibers (FRLF) with phosphorus content (<1 at %) exhibited excellent flame retardancy. The value of peak of heat release rate (PHRR) declined by 50.9 % compared with pure lyocell fibers (LF), as micro-combustion calorimetry measurement estimated. Meanwhile, the breaking strength of FRLF increased by 6.44 % compared with that of LF. In brief, this work balanced the flame retardancy and mechanical properties of lyocell fibers via one-step synthesizing fire retardant cellulose-based filler based on the structural similarity between matrix and flame retardant.
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•Ionic liquid as green modifier was used to modify cellulose powder by one-step.•Fire retardant cellulose-based filler was successfully synthesized.•Phosphorylated cellulose, fire retardant filler, was introduced to lyocell fibers.•Flame retardancy and mechanical strength of lyocell fibers achieved a balance.
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