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The use of biobased flame-retardant (FR) agents for reducing the flammability of polyester/cotton (T/C) blend fabrics is highly desirable. In this study, a novel and sustainable phosphorus/nitrogen-containing FR, namely, phytic acid–urea (PA-UR) salt, was synthesized. The PA-UR salt was further used to enhance the FR performance of T/C fabric through surface modification. We further explored the potential chemical structure of PA-UR and the surface morphology, thermal stability, heat release capacity, FR properties, and mode of action of the coated fabric. The coated fabric achieved self-extinguishing and exhibited an increased limiting oxygen index of 31.8%. Moreover, the coated T/C blend fabric demonstrated a significantly reduced heat release capacity, indicating a decreased fire hazard. Thermogravimetric analysis revealed the anticipated decomposition of the coated T/C blend fabric and a subsequent increase in thermal stability. The burned char residues also maintained their fiber shape structures, suggesting the presence of condensed FR actions in the PA-UR-coated T/C blend fabric. [ABSTRACT FROM AUTHOR]

Polyester/cotton (T/C) blend fabrics are highly flammable due to the particular "scaffolding effect". In this work, an intumescent flame retardant (IFR) agent containing P, N, and B was designed and synthesized using bio-based phytic acid, pentaerythritol, boric acid, and urea. The IFR compounds were deposited onto a T/C blend fabric by the surface-coating route. The chemical structure of IFR agent and its potential cross-linking reactions with T/C fibers were characterized. The morphology, thermal stability, heat-release ability, flame retardancy, and mechanism of coated T/C blend fabrics were explored. The self-extinguishing action was observed for the coated T/C blend fabric with a weight gain of 13.7%; the limiting oxygen index (LOI) value increased to 27.1% versus 16.9% for a pristine one. Furthermore, the intumescent flame retardant (IFR) coating imparted T/C blend fabrics with high thermal stability and significantly suppressed heat release by nearly 50%. The char residue analyses on morphology and element content confirmed the intumescent FR action for coated T/C blend fabrics. The prepared IFR coating has great potential to serve as an eco-friendly approach for improving the flame retardancy of T/C blend textiles. [ABSTRACT FROM AUTHOR]

• Nano-Mg(OH) 2 and cyclic phosphate ester penetrated inside the fiber interior. • The modified R-PET exhibited durable flame retardancy without dripping. • The modified R-PET displayed significantly reduced smoke emission. • The organic-inorganic system offers high flame retardancy, wash durability and smoke suppression to R-PET textiles. Recycled poly(ethylene terephthalate) (R-PET) fabrics offer a sustainable and eco-friendly alternative to virgin PET but exhibit high flammability and increased smoke emission. In this study, magnesium hydroxide nanoparticles (nano-Mg(OH) 2) with the particle size of 53 nm were synthesized and combined with cyclic phosphate ester through high-temperature and high-pressure immersion technology. The organic‒inorganic flame retardant (FR) agents were expected to penetrate the R-PET fibers, thus achieving high washing durability for flame retardancy and smoke suppression. The surface structural performance of nano-Mg(OH) 2 and the smoke and heat suppression capacity, FR performance, mechanism and laundering resistance of the modified R-PET samples were also explored. The organic‒inorganic FR system significantly improved the FR properties and anti-dripping ability of R-PET while significantly reducing smoke and heat generation. Moreover, the modified R-PET fabrics exhibited self-extinguishing ability even after 40 washes, indicating their high washing resistance. The organic‒inorganic FR system was effective in both gas and condensed phase, providing multilevel fire safety. This study provides efficient and durable FR-functionalized R-PET fabrics with low smoke suppression and high fire safety. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • An adhesive and hydrotropic nanoparticle with a core–shell structure (Car@DOPO) was synthesized. • Car@DOPO nanoparticle endows polyamide 6 with excellent UV shielding and outstanding flame retardancy. • Carbohydrate Caramel shows promise as a biomaterial for improving the washing durability of functional textiles. • This work demonstrates the successful and sustainable treatment of Polyamide 6 fabrics using a carbohydrate polymer. The destruction of polyamide 6 (PA6) fabrics due to fire and prolonged UV radiation is an urgent issue that needs to be addressed. Inspired by the adhesion and inclusiveness of the sugar-coated haws, this study developed an adhesive nanoparticle with a core–shell structure (Car@DOPO) by encapsulating DOPO with carbohydrate caramel. The Car@DOPO nanoparticles exhibited excellent UV shielding property on PA6 fabrics, as indicated by a maximum UPF of 41.7, which can be attributed to the π-bonds and dark brown color of caramel shell. Additionally, the coated PA6 fabric demonstrated good flame retardancy, with a flame retardancy index (FRI) of 1.2. The LOI of coated PA6 fabric improved from 22.1% to 30.5%. Moreover, the fire growth rate (FGR) and flame inhibition effect (FIE) decreased by 13.3% and 22.0%, respectively. These improvements can be attributed to the efficient quenching effect of the DOPO core. Notably, the strong adhesion of the caramel shell allowed the Car@DOPO nanoparticles to firmly adhere to the fabric surface, providing coated PA6 fabric with durable flame retardancy. This study demonstrates the successful and sustainable treatment of PA6 fabrics using a carbohydrate nano-polymer. [ABSTRACT FROM AUTHOR]

The flame-retardant (FR) properties of polyurethane (PU)-coated polyester fabrics used in outdoor settings are unsatisfactory. This study aimed to enhance the FR performance of PU-coated polyester fabrics by synthesizing a series of metallic phytate salts through the chelation of phytic acid and four metal ions (Mg2+, Fe2+, Fe3+, Al3+). The flame retardancy, washing durability, mechanical properties, combustion performance, and FR mechanism of coated PET fabrics were investigated. Among the different metallic phytate salts, phytate aluminum salt exhibited stable FR efficiency without significantly affecting the mechanical performance of the fabric. The coated polyester fabric with 4 wt% phytate aluminum salt possessed a high LOI of 34.2 %, and achieved self-extinguishing action and met the requirements for B 1 classification. The coated fabric also displayed remarkable flame retardancy and durability, even after undergoing 50 washing cycles. Moreover, the addition of phytate aluminum salt resulted in a significant reduction of 34.3 % and 56.8 % in total heat and smoke release, respectively, indicating high fire safety. The phytate aluminum salt acted as a catalyst for the dehydration and carbonization of the PU-coated polyester in the condensed phase. This research introduces a novel approach for producing sustainable and long-lasting FR PU-coated polyester fabrics. [Display omitted] • Phytate salt is derived from resourceful plants or crops. • Phytate aluminum salt has high flame retardancy and washing durability on PU-coated polyester fabric. • Phytate aluminum salt significantly reduced the smoke and heat production of PU-coated polyester fabric. • Phytate aluminum salt offers an eco-friendly, long-lasting flame-retardant system for PU-coated outdoor polyester fabric. [ABSTRACT FROM AUTHOR]

• The coated polyester/spandex (T/S) fabrics displayed excellent washing and rubbing fastness. • The coated T/S fabrics had excellent UV protection and antistatic properties. • The coated T/S fabrics possessed significantly improved flame retardancy and anti-dripping performance. • This study offers a sustainable and promising technique to impart multi-functionalities to T/S fabrics. This study focused on the development of liquid carbon black nanoparticles (nano-CB) and the fabrication of black-colored polyester/spandex (T/S) fabrics with antiultraviolet, antistatic, and flame-retardant properties by a facile pad-cure technique. The flame retardancy efficiency and fastness of nano-CB on the fabric were enhanced by using a cyclic phosphate ester-based flame-retardant and polyacrylate adhesive binder HF-901. The morphology and particle size of nano-CB were investigated, and the color features, antiultraviolet and antistatic properties, combustion behavior, flame retardancy, and mechanism of coated T/S fabrics were also explored. The flaky nano-CB particles provided excellent light shielding and color fastness to the fabrics. The homogeneous coating of nano-CB also significantly improved the antiultraviolet and antistatic performance of the fabrics. Moreover, the coated T/S fabrics exhibited self-extinguishing capacity and a reduced damaged length of approximately 7.9 cm without molten drops. The formation of cross-linked char networks in the condensed phase and the trapping of combustible radicals in the gas phase during combustion synergistically enhanced the flame retardancy and anti-dripping capacity of the coated T/S fabrics. This study offers a facile and industrial applicable approach to enhance the multifunctionality of T/S fabrics and expand their potential applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Inorganic magnesium hydroxide nanoparticles (Mg(OH) 2 NPs) offer a promising halogen-/phosphorus-free flame-retardant solution for silk. However, achieving effective and durable flame retardancy remains a challenge. In this study, silane-modified Mg(OH) 2 NPs were prepared using the double drop-reverse precipitation method with the silane coupling agent 3-aminopropyltriethoxysilane as a surface modifier. The chemical bonding between silane-modified Mg(OH) 2 NPs and silk fabric was beneficial for improving the stabilization and durability of the functional particles on the silk surface. The surface morphology and structure of the silane-modified Mg(OH) 2 NPs, as well as the smoke and heat generation performance, flame retardancy, washing durability, and flame-retardant mechanism of the coated silk fabrics were investigated. The coated silk fabric exhibited high flame-retardant efficiency and significantly reduced smoke and heat generation, indicating a lower fire hazard. Additionally, the coated silk fabric displayed self-extinguishing behavior even after 15 robust washings, demonstrating high washing durability. The coated silk exhibited fibrous and weave structures after combustion, indicating a strong charring ability. Overall, this study presents a promising approach for the development of flame-retardant silk fabrics with excellent washing durability using inorganic Mg(OH) 2 NPs. [Display omitted] • Silane-modified magnesium hydroxide nanoparticles (Mg(OH) 2 NPs) is applied as inorganic flame-retardant coating for silk. • Silane-modified Mg(OH) 2 NPs coating endows silk textile with effective and durable flame retardancy. • Silane-modified Mg(OH) 2 NPs coating significantly suppresses the smoke and heat generation of silk textile. • Silane-modified Mg(OH) 2 NPs coating serves as a sustainable and promising technique to minimize fire hazards of silk textile. [ABSTRACT FROM AUTHOR]

The development of sustainable, efficient and durable flame-retardant (FR) coating for silk fabric using plant-derived phytic acid is of great interest. This work synthesized a novel and reactive intumescent FR agent namely glycidyl phytate isocyanurate (GPIC) through ring-opening addition reaction using phytic acid and 1,3,5-triglycidyl isocyanurate. Then, the durable FR coated silk fabric was developed with GPIC through the surface coating route. The chemical structure of GPIC, and its cross-linking mechanism with silk, the smoke and heat generation performance, flame retardancy and washing durability of coated silk were studied. The coated silk fabric with a weight gain of 13.6 % could self-extinguish and possessed a high limiting oxygen index (LOI) value of 32.5 %. GPIC coating would be covalently cross-linked onto silk fabric and the coated silk fabric could withstand 30 washing cycles, displaying high washing durability. GPIC coating also significantly suppressed the smoke and heat generation of silk fabric during combustion. The coated silk fabrics had high thermal stability and left significant inflated char residues after the burning tests. The intumescent FR performance of GPIC was beneficial from the synergistic effect of phytate and triazine-trione groups. [Display omitted] • Sustainable and reactive glycidyl phytate isocyanurate (GPIC) intumescent flame-retardant is synthesized. • GPIC coating is grafted on silk surface through covalent reaction. • GPIC coating has high flame retardancy and durability on silk textile. • GPIC coating functions by taking advantage of synergistic action of phytate and triazine-trione groups. • GPIC coating offers an eco-friendly and durable flame-retardant approach for silk in practical applications. [ABSTRACT FROM AUTHOR]

• Sustainable and reactive pentaerythritol phytate ethylenediaminetetraacetic acid ester (PPEDTE) intumescent flame-retardant is synthesized. • PPEDTE coating is grafted on silk surface through covalent reaction. • PPEDTE coating has high flame retardancy and durability on silk textile. • PPEDTE coating offers an eco-friendly and durable flame-retardant approach for silk in practical applications. The exploitation of plant-derived phytic acid as effective and durable flame retardant (FR) for textiles is of great significance for developing novel and ecological functional textile products. In the present study, a reactive and phytate-based FR namely pentaerythritol phytate ethylenediaminetetraacetic ester (PPEDTE) prepared by the esterification of phytic acid, pentaerythritol and ethylenediaminetetraacetic acid was investigated as intumescent FR agent for silk fabric. The chemical structure of PPEDTE and its potential grafting mechanism on silk were studied. The thermal stability, heat and smoke suppression property, flame retardancy and washing resistance on silk fabric were studied. The deposition and covalently cross-linked PPEDTE on silk fabric enabled it to self-extinguish in vertical burning test. The coated silk fabric with an add-on of higher than 10.7% could withstand 15 washing cycles, displaying good washing durability. The intumescent FR coating remarkably decreased the release of heat and smoke of silk during burning. The coated silk had high thermal stability and left significant combustion residues after the burning tests. These results demonstrate that the synthesized PPEDTE warrant potential as efficient and reactive intumescent FR approach for silk. [Display omitted] [ABSTRACT FROM AUTHOR]

The exploitation of resourceful plant derivatives for fabricating durable flame retardant (FR) textiles is of great interest. Herein, this study offers a novel and facile approach for developing FR wool fabric by covalently grafting bio-based ammonium phytate (APH) onto wool fibers. The potential grafting action of APH with wool fibers, the flame retardancy and washing durability, smoke and heat emission performance and FR mechanism of modified wool fabrics were explored. The modified wool fabrics could pass the vertical burning B 1 classification with a reduced char length of approximately 10.0 cm from 30.0 cm, and they also had an increased LOI of approximately 32.0% from 23.6%. The modified wool fabrics possessed increased tensile strength; they also self-extinguished during the vertical burning test after 15 washing cycles, which was attributed to the cross-linking action of APH with wool fibers. Besides, a significant reduction in smoke and heat release of wool fabric was achieved after FR grafting. The investigations on char residue confirmed the intumescent FR mechanism for APH modified wool fabrics. In general, the present study provides an industrial feasible strategy to prepare sustainable and durable FR wool fabrics using phytate derivatives. [Display omitted] • Phytate derivative APH is obtained from resourceful crops. • APH covalent grafting approach is a green, sustainable and promising technique. • APH covalent grafting approach shows high flame-retardant efficiency and durability on wool fabric. • APH covalent grafting approach offers a cleaner and industrial feasible way to minimize fire hazards of wool textile. [ABSTRACT FROM AUTHOR]

• Highly sticky functional coating is in-situ fabricated on silk surface. • The functional coating is grafted on silk surface through covalent reaction. • The functional coating has high flame retardancy and thermal stability on silk textile. • The functional coating pyrolyzes through intumescent charring mechanism. • The functional coating offers an effective and durable strategy to minimize fire hazards of silk textile. The novel strategies for fabricating durable flame retardant (FR) silk fabric with biomass phytic acid (PA) is of interest. In this study, a highly sticky coating was in-situ developed on the surface of silk fabric by adsorption of PA, 1,4-Phthalaldehyde and followed by adsorption of 3-aminopropyltriethoxysilane (KH550). The Schiff base reaction would occur between 1,4-Phthalaldehyde and silk fiber/KH550, and thus the sticky coating could be firmly grafted on silk surface. The thermal degradation, smoke and heat emission properties, flame retardancy, and washing durability of coated silk were explored. The FR coating displayed high functional efficiency and thermal stability by taking advantage of synergistic effect with phosphate groups and silica networks. The modified silk fabrics also possessed lower fire hazards as suggested by significantly reduced smoke and heat generation. The coated silk fabrics self-extinguished and obtained a char length of 13.5 cm after 20 washing cycles. The improved washing resistance should be ascribed to the covalently grafted sticky coating on silk surface. In general, this work reports a novel and feasible strategy to develop durable silk textile using bioderived PA. [Display omitted] [ABSTRACT FROM AUTHOR]

• Phytic acid and taurine are derived from different crops. • Phytate taurine salt (PTS) is successfully synthesized by ion reaction. • PTS coating displays high flame retardant efficiency and anti-dripping ability on PA6 fabric. • PTS coating mainly works in condense- and gas-phase. • PTS coating offers an effective and cleaner strategy to minimize fire hazards of PA6 textiles. Eco-friendly and sustainable flame retardant (FR) approaches derived from natural products for polyamide 6 (PA6) fabrics are of interest. Therefore, a novel biomass phytate taurine salt (PTS) was synthesized using phytic acid and taurine, and then it was coated onto PA6 fabric. The chemical structure of PTS, and the flame retardant performance and mechanism, the washing durability and physical properties of coated PA6 fabrics were explored. The damaged length of coated PA6 fabrics reduced to 12.0 cm without droplets during the vertical burning test, achieving a UL94 V-0 level. The LOI increased from 23.0% to 31.8% after PTS coating. The results of cone calorimetry showed that the pHRR of PA6-PTS sample decreased by about 11.0% with a char residue of 12.0%. The investigations on violates and char residues confirmed that PTS coating improved the flame retardancy of PA6 fabric through a combined gas-phase and condensed-phase action. In addition, the coated PA6 fabrics could still maintain V-0 level after 15 washing cycles. The tensile strength of PA6 fabrics was also slightly improved after PTS coating. In general, this work developed a durable and sustainable PTS coating with excellent flame retardancy for PA6 fabric. [Display omitted] [ABSTRACT FROM AUTHOR]

² Reactive synergistic P/Si/N-containing hybrid silica sol system is prepared. ² Hybrid silica coating has high flame retardancy and washing durability on silk textile. ² Hybrid silica coating acts as the intumescent charring flame-retardant action. ² Hybrid silica coating offers an effective and durable strategy to minimize the fire hazards of silk textile. The fabrication of phosphorus-doped sol-gel coatings for durable flame retardant (FR) modification of textiles are of interest. This study facilely synthesized a novel phosphorus-doped silica sol system using 3-aminopropyltriethoxysilane, glutaraldehyde, diethyl phosphite by simultaneous Kabachnik-Fields and sol-gel reactions. The morphology and chemical structures of hybrid silica particles were studied by TEM, FT-IR and NMR. Then, the hybrid silica sol was applied as durable FR coating to reduce the flammability of silk. The FR property and washing durability, smoke and heat generation capacity, thermal stability, and FR mechanism of coated silk fabrics were explored. The hybrid silica coating displayed good FR performance because of the synergistic action among Si, P and N. The coated fabrics self-extinguished after 25 launderings and had a high LOI value of 28.0% thanks to the covalent grafting of hybrid silica coating on silk fabrics. The explorations on silk residues confirmed the intumescent FR mechanism of coated silk. The hybrid silica coating is promising to functional as feasible and durable FR strategy for silk fabric. [Display omitted] [ABSTRACT FROM AUTHOR]

Developing durable and sustainable flame retardant (FR) polyamide 6 (PA6) fabric is of great interest. Herein, an eco-friendly Maillard reaction product (MRP) was developed by carbonyl-amino condensation between glucose and thiourea. Then, the functional PA6 fabric was developed through an exhaustion process. We further explored the anti-dripping ability, flame retardancy and washing durability, FR mechanism and physical properties of MRP-modified PA6 fabric. The modified PA6 fabric possessed a high LOI of 31.6% and a low damaged length of 11.3 cm without dripping action. The smoke emission was also reduced by 38.2% after MRP modification, although the Caramel skeleton exerted a scaffold effect with PA6. The MRP macromolecule inhibited PA6 flammability through gas-phase FR mechanism. In addition, the MRP macromolecule could firmly adsorb on PA6 fabric, corresponding to superior washing durability, and the V-0 rate was also reached after 40 washings. The modified PA6 fabric also had a yellowish-brown color and improved tensile strength. [Display omitted] • Glucose and thiourea are derived from multiple plants or microorganisms. • Maillard reaction product (MRP) is a carbohydrate compound with good adhesion ability. • MRP macromolecule displays high flame retardant efficiency through gas-phase mechanism. • MRP macromolecule offers a sustainable and durable strategy to minimize the fire hazards of polyamide 6 textiles. [ABSTRACT FROM AUTHOR]

The development of halogen- and phosphorus-free flame-retardant strategies is urgently needed in textile industry. In this study, a caramel product doped with aromatic compounds was developed via caramelization and aldol reactions using glucose and p-phthaldialdehyde. The modified caramel (Car@PDA) was subsequently used as a sustainable approach to improve flame retardancy of wool fabric. The flame retardancy, washing durability, heat generation, and flame-retardant mode of action of Car@PDA on wool fabric were investigated. The modified wool fabrics showed excellent flame retardancy, with the limiting oxygen index increasing to 32.5 % and the damaged length decreasing to 10.1 cm, with good self-extinguishing capacity. Car@PDA could combine with wool fibers through Schiff base reaction and electrostatic attraction, so the modified wool fabrics still self-extinguished and met the B1 flame-retardant requirements after 10 washing cycles. The modified wool showed significantly decreased heat release capacity and fire growth rate, suggesting high fire safety. Car@PDA promoted the decomposition of the fabric to form char barrier, thereby achieving an effective flame-retardant effect. In addition, the Car@PDA modification had a minimal effect on the tensile strength and handle of wool fabric. This study provides an innovative way to create bio-based, halogen- and phosphorus-free flame-retardants for protein wool fabrics. [Display omitted] • The modified caramel (Car@PDA) exhibits good flame retardancy and washing durability on protein wool fabrics. • Car@PDA can significantly reduce the heat emission of wool fabrics. • Car@PDA functions by an intumescent charring mechanism. • Car@PDA is promising as a cleaner, nonhalogen and nonphosphorus flame-retardant approach for wool fabrics. [ABSTRACT FROM AUTHOR]

The facile development of a sustainable and durable flame-retardant approach for protein silk is of interest. Inspired by silk tin-weighting technology, this study developed a novel and sustainable in-situ deposition strategy based on biomass phytic acid to impart durable flame-retardant performance to silk fabrics. The chemical structure of insoluble chelating precipitation, and the surface morphology, thermal stability, combustion behavior, flame-retardant capacity, laundering resistance, and flame-retardant mode of action of the tin-weighting silk samples, were explored. The Sn-, P-, Si-containing insoluble chelating precipitation formed within the fiber interior and combined with silk fibers through electrostatic attraction and metal salt chelation. As a result, the tin-weighting silk displayed excellent self-extinguishing capacity, with the damaged length reduced to 9.2 cm and the LOI increased to 31.6 %; it also achieved self-extinguishing after 30 washing cycles, demonstrating high flame-retardant efficacy and laundering resistance. Moreover, the tin-weighting silk also showed the obvious suppression in smoke and heat generation by 55.6 % and 35.7 %, respectively. The synergistic charring action of phosphate groups, tin metal salts, and silicates was beneficial for enhancing the fire safety of silk. The tin-weighting treatment also displayed a minor impact on mechanical performance of silk fabrics. [Display omitted] • The tin-weighting treatment involves the stepwise adsorption of tin chloride, phytic acid and sodium silicate. • Insoluble chelating precipitations are in-situ deposited inside silk fiber interior. • The tin-weighting treatment exhibits excellent flame retardancy and good washing durability on silk fabrics. • The tin-weighting treatment exerts a minor impact on mechanical property of silk. [ABSTRACT FROM AUTHOR]

The durable flame-retardant functional coating of polyester/cotton (T/C) blend fabrics is both interesting and challenging. In this study, a novel in-situ polymerization strategy for phosphorus/nitrogen-based flame-retardant on T/C blend samples was developed through the polycondensation of tetramethylolphosphonium sulfate, dicyandiamide, and anionic cyclic phosphate ester. The chemical structure of the polycondensation compounds, as well as the surface morphology, combustion behavior, flame-retardant capacity, washing durability and flame-retardant mechanism of the coated T/C blend fabrics, were investigated. The coated T/C blend fabrics demonstrated excellent self-extinguishing performance, with the damaged length decreasing to as low as 8.0 cm and the LOI reaching 28 %. Moreover, the peak heat release rate of the coated T/C blend fabrics decreased by 39.7 %. The superior flame retardancy can be attributed to the enhanced dehydration and carbonization by phosphate groups in the condensed phase, as well as the quenching effect and diluting effect in the gas phase. Additionally, the coated T/C blend fabrics exhibited remarkable washing durability and still achieved self-extinguishing after 65 washing cycles, and the in-situ deposition of insoluble three-dimensional polycondensation compounds onto the T/C blend fabrics was beneficial. The flame-retardant coating had a minor impact on the whiteness, tensile strength and breathability of the T/C blend fabrics. [Display omitted] • Insoluble polycondensing compounds were in-situ deposited inside fiber interior. • The polycondensing compounds had high affinity to both cotton and polyester. • The coated T/C fabrics displayed high flame retardancy and washing durability. • The in-situ polymerization strategy was feasible and industrially applicable. [ABSTRACT FROM AUTHOR]

[Display omitted] • Squid ink (SI) can be obtained from waste ink glands. • Squid ink is rich in proteoglycan, melanin, and metal ions. • The treated silk exhibit superior flame retardancy, good UV protection and washing durability. • The proposed approach offers a sustainable and cleaner method for creating high value-added silk. Today, marine biomolecules have attracted great interest in the field of flame-retardant (FR) science due to their sustainability and charring properties. Squid ink is mixed bio-colloid rich in proteoglycans, melanin, and metal ions. Here, squid ink was applied to endow silk with outstanding FR performance and ultraviolet protection through surface coating. After coating with 40 g/L squid ink, silk displayed excellent ultraviolet shielding performance with a high UV protection factor (UPF) of 71.5, attributing to powerful ultraviolet absorption ability of melanin. Besides, the coated silk also exhibited outstanding FR performance, characterized by a shorter char length (7.1 cm) and a higher FR-Index (2.5). The heat release performance of the treated silk dramatically decreased, and the peak heat release rate (pHRR) and heat release capability (HRC) both decreased by 49.1 %. Moreover, a significant reduction in total smoke production (TSP ∼ 60 %) was also observed in cone calorimetry test. A reduction in these fire parameters indicated a great improvement in the fire safety of silk. Interestingly, due to the natural adhesiveness of the proteoglycan mixed colloid, the coated silk could withstand 10 washing cycles while maintaining FR properties. Subsequently, further analyses of the cone residues confirmed the formation of a compact and stable char layer. The squid ink coating exerted an intumescent FR action on silk. [ABSTRACT FROM AUTHOR]

The utilization of carbohydrate polymers to develop multifunctional textiles is of significant importance to address current societal needs of developing sustainable functional materials. Here, a facile and durable bio-polymer coating methods for the development of high-performance polyamide 6 (PA6) fabrics with superior UV protection, antibacterial and flame retardancy is proposed. In this study, a highly sticky multifunctional modifier (DOPO-MRP) was synthesized by reacting DOPO and Maillard product through Kabachnik-Fields reaction. After coating with 60 g/L DOPO-MPR, PA6 fabric exhibited excellent UV protection and good antibacterial performance, as indicated by a UPF of 54.6 and high inhibition rate of 85.5 % and 93.3 % against E. coli of and S. aureus , respectively. Additionally, the coated PA6 fabric also obtained outstanding self-extinguishing and anti-dripping performance with a high LOI of 32.3 %. The results of cone calorimetry on the treated fabric suggested a significant reduction in total heat release (THR ∼ 42.4 %) and flame inhibition effect (FIE∼59.4 %). Other highlight noted was the excellent washing durability of the treated fabrics, which was attributed to the strong adhesion and film-forming properties of DOPO-MRP. Evolved gas analysis with TG-IR and char analyses confirmed the bi-phase action of DOPO-MRP. Thus, DOPO-MRP coatings display great application prospects towards multifunctional PA6 materials. [Display omitted] • Maillard colloid refers a safety and favorable food additive. • A green and sustainable multifunctional coating (DOPO-MRP) was synthesized. • Functional polyamide 6 fabrics displays excellent fire-proof, high antibacterial and good UV blocking properties. • This work provides a cleaner and sustainable approach for preparing durable and multifunctional polyamide 6 fabrics. [ABSTRACT FROM AUTHOR]

The incorporation of metal-organic frameworks (MOFs) on textile materials to enhance flame retardancy is of interest and challenge. In this study, an iron-rich MOF (Fe-MOF) was constructed in situ on wool fabric surface through the alternating assembly of ferric metal salt and the carboxylic acid ligand 1,3,5-benzenetricarboxylic acid. The surface morphology, flame retardancy, smoke and heat release performance, thermal stability, and flame-retardant mechanism of the Fe-MOF coated wool fabric were investigated. Square-shaped crystals were observed on the coated wool fabric, indicating successful construction of Fe-MOF on the wool surface. The coated wool fabric with an add-on of 6.8 % exhibited excellent flame retardancy, as evidenced by its self-extinguishing ability during the vertical burning test and a significantly enhanced limiting oxygen index of 32.6 %. Moreover, the coated wool fabric demonstrated a remarkable reduction in heat and smoke production of 23.8 % and 68.4 %, respectively, indicating enhanced fire safety. The analysis of char residue, including thermal stability, surface morphology, iron content, and graphitization degree, supported the formation of ferric oxides as a protective layer, contributing to the improved flame retardancy of the Fe-MOF coated wool in the condensed phase. The in situ construction of Fe-MOF on wool macromolecules offers a promising and innovative approach for developing nonhalogen and nonphosphorus flame-retardant systems. [Display omitted] ● The iron-rich metal-organic frameworks (Fe-MOF) is in situ loaded on wool surface. ● The Fe-MOF coating exhibits high flame retardancy and smoke suppression capacity. ● The Fe-MOF coating mainly functions in the condensed phase. ● The Fe-MOF coating serves as halogen-free, phosphorus-free flame-retardant system. [ABSTRACT FROM AUTHOR]

For protein fibers, polycarboxylic acids represent a green strategy to enhance durability without using formaldehyde. This study evaluated the physical and flame retardant properties of silk fabrics treated with three formaldehyde-free crosslinkers: citric acid (CA), 1,2,3,4-butanetetracarboxylic acid (BTCA), and 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA). Results showed that these acids bond with silk protein through esterification and amidation, improving washing durability. Particularly, PBTCA integrates phosphorus into silk, boosting flame retardancy. While BTCA led to the highest weight gain and improved wrinkle recovery, it negatively impacted the tensile strength and softness of silk fabrics. Conversely, PBTCA adeptly balanced enhanced wrinkle resistance with minimal effects on tensile strength and softness, and least affected the silk fabrics' whiteness, thus preserving its aesthetic appeal. All crosslinkers improved flame retardancy, but PBTCA displayed superior performance, achieving a limiting oxygen index of 32.4 % at an 80 g/L concentration. In vertical burning tests, PBTCA treated silk fabrics showed reductions in damage length and demonstrated self-extinguishing properties, qualifying them for a higher flame retardant grade. Phosphorus in PBTCA promotes char formation during combustion, essential for effective flame retardation and smoke reduction. This research highlights the exceptional potential of silk treated with PBTCA, showcasing its suitability for demanding applications. [Display omitted] • Three acids improve flame retardancy of silk, with PBTCA showing superior results. • Silk's wrinkle resistance was enhanced by polycarboxylic acids. • PBTCA treatment maintains silk's original whiteness and softness. • Silk treated with polycarboxylic acids showed reduced smoke release during fire. [ABSTRACT FROM AUTHOR]

• The TEMs particles displays high expansion performance on PET fabric. • The PET@TEMs/APP composite fabric possesses low thermal conductivity and displays high thermal insulation performance. • The PET@TEMs/APP composite fabric displays high flame retardancy. • The PET@TEMs/APP composite fabric is promising to serve as soft and safety thermal insulation material for energy saving. The development of thermally resistant textiles with fire safety using thermo-expandable hollow microsphere (TEHM) has garnered significant interest. In this study, TEHM and ammonium polyphosphate (APP) were bonded to polyester fabric surface by using polyurethane coating. The surface morphology, thermally resistant, flame-retardant performance and mechanism of the developed PET@TEHM/APP composite fabric were investigated. The PET@TEHM/APP composite fabric exhibited the reduced thermal conductivity of 0.07458 W/m·K from 0.13120 W/m·K of pristine PET fabric. The thermal conduction and radiation performance of the PET@TEHM/APP composite fabric decreased owing to the low thermal conductivity of the expanded TEHM. The PET@TEHM/APP composite fabric presented a damaged length of 13.5 cm without melt dripping, achieving the B 1 classification. The peak heat release of the PET@TEHM/APP composite fabric decreased by 58.3 % versus pristine PET fabric according to cone calorimetry test. PET@TEHM/APP composite fabric also had an FRI of 1.001, showing 'Good' flame retardancy performance. TG-IR and char residue analyses suggested that the flame retardancy of PET@TEHM/APP composite fabric improved by the synergic flame-retardant action in both gas and condensed phases. [Display omitted] [ABSTRACT FROM AUTHOR]

Polyurethane (PU)-coated polyester fabrics are commonly used in outdoor settings, but their flame-retardant properties are somewhat lacking. In this study, biomass phytate salt was applied to improve the flame retardancy and anti-dripping properties of PU-coated polyester fabrics. This study also explored the hydrostatic pressure, mechanical performance, heat release capacity, flame retardancy, washing durability, and mode of action of coated polyester fabrics. The polyester fabric coated with 4 % phytate salt-modified PU exhibited impressive self-extinguishing properties without any dripping. Additionally, the coated polyester fabric showed a low damaged length of 12.2 cm and a high LOI of 33.8 %, satisfying the requirements for the B 1 level. The coated polyester fabric proved to withstand 50 washing cycles, highlighting its remarkable flame retardancy efficiency and durability. It also exhibited a significant reduction in heat release, suggesting the fire safety performance. Analysis of the thermal resistance and char residue revealed a condensed flame-retardant mechanism attributed to the phytate-based system. Overall, phytate salt shows promising potential as a long-lasting flame-retardant system for outdoor PU-coated polyester fabrics. [Display omitted] • Phytate salt is derived from resourceful plants or crops. • Phytate salt has high flame retardancy and washing durability on PU-coated polyester. • Phytate salt exhibits excellent compatibility with polyurethane. • Phytate salt offers a long-lasting flame-retardant system for PU-coated outdoor polyester fabric. [ABSTRACT FROM AUTHOR]

The growing awareness of human health and environmental protection stimulates the development of more sustainable flame retardant (FR) approaches. In this study, polyaniline (PANI) with a nitrogen-containing aromatic structure was synthesized as a novel functional compound to improve the FR and UV protection performance of silk fabric. Biobased chitosan was applied to develop the PANI/chitosan coating to improve the binding capability and dispersion uniformity of PANI on the silk surface. The surface morphology, thermal resistance, heat generation capacity, flame retardancy and UV protection performance were explored. The PANI/chitosan coating with 3 wt% PANI endowed the silk fabric with effective flame retardancy. The coated silk fabric self-extinguished during vertical flammability test and possessed a decreased char length of 9.5 cm versus 30 cm of the pristine silk fabric; it could also withstand 20 launderings, showing good laundering resistance. The coated silk fabric displayed markedly decreased heat release behavior. A combined condensed phase and gas phase FR action was suggested for the PANI/chitosan coating on silk fabric. The coated silk fabric also exhibited excellent UV protection with the UPF of 50+ because of the UV-shielding of PANI. [Display omitted] • Polyaniline (PANI) is applied as halogen-/phosphorus-free flame-retardant for silk. • PANI/chitosan coating imparts effective flame-retardant and UV protection properties for silk textile. • PANI/chitosan coating works by the combined condensed and gas phase action. • PANI/chitosan coating serves as a sustainable and promising technique to minimize fire hazards of silk textile. [ABSTRACT FROM AUTHOR]

Nowadays, high value-added and multifunctional textiles have attracted widespread attention due to the changing demands of modern life. This study focused on the fabrication of silk with photochromism, flame retardancy, UV resistance and durability using riboflavin sodium phosphate (RSP) and various metal ions (Fe2+, Fe3+, Al3+, and Ti4+). Attractively, the photochromic performance was one of the most distinctive features of the modified silk, and the yellow silk fabric turned into fluorescent green under UV lamp. After a detailed comparison, it was determined that RSP/Fe3+ hybrid system was most effective in improving anti-UV performance of the silk with a high UPF of 25.8, achieving a "Good" level of UV protection. Specifically, it achieved a B 1 fire protection with a low damaged-length of 9.4 cm and a high LOI of 28.3 %. Additionally, the modified silk showed the lowest smoke density, reducing by approximately 84.1 % versus that of pristine silk. Moreover, the modified silk was able to meet the B 1 classification and the "Good" UV protection requirements even after 75 washing cycles, making it more durable than most functional textiles reported. The further analysis indicated that RSP and metal ions can synergistically enhance the condensed-phase action, thereby improving the fire resistance of silk. [Display omitted] • A sustainable multifunctional organic-inorganic hybrid system is fabricated using bio-macromolecule Vitamin-B 2 derivative. • The modified silk has superior durable flame retardancy, good UV protection and photochromism performance. • Complexing action solves the poor durability of Vitamin-B 2 derivative in the field of dyeing and finishing. • The proposed approach offers a sustainable and cleaner method for creating high value-added silk. [ABSTRACT FROM AUTHOR]

• DOPO coating is constructed by hydration reaction. • DOPO coating with a super-low p content displays good flame retardancy and anti-dripping ability on PA6 fabric. • DOPO coating effectively inhibits heat propagation and improves fire safety. • DOPO coating mainly works in gas-phase. The application of insoluble 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) to develop a durable coating for flame retardant (FR) modification of polyamide 6 (PA6) is of concern and difficult. This study found that the hydration reaction of DOPO provided the possibility of constructing a DOPO coating. Hence, DOPO compound was deposited onto PA6 fabric by dip-coating technique. Then, the impacts of DOPO coating on FR performance, anti-dripping property, smoke and heat release performance of coated PA6 fabric were systematically studied. The limiting oxygen index (LOI) of PA6 fabrics continued to increase with the increase of phosphorus content. However, the coated PA6 fabrics achieved anti-dripping property at a phosphorus content of 0.88 ∼1.75 mg/g. Besides, the heat release ability of coated PA6 reduced sharply at high phosphorus content of 1.75 mg/g, as suggested by a reduction of 20.9% and 21.8% in pHRR and THR, respectively. Moreover, DOPO coating exhibited good washing durability on PA6 fabric because of the hydrogen bond formed between DOPO and PA6, as well as the adhesion of DOPO coating. The coated PA6 fabric could still self-extinguish after 15 washing cycles. Further analysis proved that DOPO played a quenching role in the gas-phase with a weak condensed-phase action. This work points out the right direction for the future research on the preparation of FR PA6 fabric using DOPO derivatives. [Display omitted] [ABSTRACT FROM AUTHOR]

Cotton and calcium alginate (CA) fibers are both polysaccharide-based fibers, but they possess different flame retardancy. The detailed comparisons on flame retardancy and combustion behavior of polysaccharide fabrics are of interest. In this study, the difference between the fabrics made of these two fibers in the combustion process, pyrolysis products and the morphology and chemical structures of char residues were performed by vertical burning, thermal gravimetric analysis, Fourier Transform Infrared Spectrometer (FTIR) and scanning electron microscopy. Compared with cotton fabric, CA fabric had no after-flame when it was burned vertically, and the smoldering time was longer. Especially, the smoke release rate, peak heat release rate and total heat release were much lower versus cotton fabric, indicating that CA fabric had much lower fire hazards than cotton fabric. The results of thermogravimetric analysis coupled with FTIR (TG-FTIR) suggested that CA fabric exhibited a different thermal degradation pathway versus cotton fabric. Under the same quality, CA fabric produced more char residues after combustion, and chrysanthemum-like calcium oxide were generated on the surface of char residues as protective barrier, leading to the enhanced flame retardancy of CA fabric. [Display omitted] • Alginate and cotton fibers have similar polysaccharide structures but different flame retardancy and combustion behavior. • Systematic and in-depth comparative studies are carried out on combustion process/products and fabric structure of polysaccharide-based fabrics. • Calcium alginate produces chrysanthemum-like calcium oxide char structures as protective barrier. • Calcium alginate fabric has significantly decreased fire hazards versus cotton fabric. [ABSTRACT FROM AUTHOR]

[Display omitted] • Phytic acid and Thiourea are derived from plants or fungi metabolites. • Phytic acid and Thiourea both act as acid source and mutual synergists. • Intumescent flame retardant (IFR) coating displays outstanding anti-dripping and char forming ability on PA6 fabric. • IFR coating mainly works in condensed- and gas-phase. • IFR coating offers an effective and cleaner strategy to minimize fire hazards of PA6 textiles. This study focused on the construction of an eco-friendly and intumescent flame retardant (FR) coating for polyamide 6 (PA6) fabric. The intumescent FR coating, consisting of phytic acid, pentaerythritol and thiourea, was deposited onto PA6 fabric through dip-coating technique. The FR performance, anti-dripping ability, thermal stability, combustion behavior and mechanical property of the coated PA6 fabrics were explored. The severe dripping of coated PA6 fabric was totally eliminated, achieving an excellent FR performance at a low P (2.2%) and S (3.4%) content. Correspondingly, the LOI increased to 28.8% versus 23.2% of pristine one, displaying good flame retardancy. The char residue analyses confirmed the intumescent FR behavior of coated PA6 fabrics. The intumescent char layer played a major role in isolating the exchange of combustibles, oxygen and heat, leading to the significant reduction in heat release performance. The results of cone calorimetry test showed that the peak heat release rate and average effective heat of combustion of coated PA6 fabric decreased by about 36.5% and 34.4%, respectively versus pristine one. Meanwhile, the sulfur-based gases captured free radicals to interrupt the continuous combustion, leading to the significantly improved flame retardancy. Furthermore, the FR coating exerted little influence on the mechanical performance of PA6 fabric. [ABSTRACT FROM AUTHOR]