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A carbohydrate compound originated from plant species, namely oxidized sucrose (OS) was used as a cross-linking agent to stabilize the layer by layer (LbL) deposited flame retardant coatings developed onto the polyamide 66 textile surfaces. Here, the coating was constructed using some polyelectrolytes like chitosan (CS), sodium alginate (SA), phytic acid (PA) and montmorillonite (MMT) derived from green and mineral sources in a LbL assembly and subsequently, this coating was further treated with a polysaccharide binder like starch and a cross-linking agent like OS. In line, another bio-derived cross-linker, namely citric acid (CA) was used instead of OS and compared herewith. Obtained results showed that OS revealed superior coating stability over CA and in line, OS treated PA66 textiles exhibited better flame retardancy compared to the CA treated one. For example, OS treated fabrics attained a maximum limiting oxygen index (LOI) value by 23.5% along with a significant reduction in the peak heat release rate (pHRR) and total heat release rate (THR) by 36% and 15%, respectively. Meanwhile, OS could improve the stability of such coatings and offer extended durability in flame retardant performance. Thus, it was revealed that oxidized sucrose exhibited its potential to be considered as an effective green flame retardant alongside its cross-linking ability. [Display omitted] • O-Sucrose (OS) and citric acid (CA) were used to stabilize the LbL coating. • O-Sucrose provided better coating stability and flame retardancy than citric acid. • Green polyelectrolytes like chitosan and sodium alginate were used in LbL assembly. • The pairing of phytic acid with OS handed a substantial reduction in pHRR by 36%. • O-Sucrose treated PA66 could retain UL-94V1 rating even after 10 laundering cycles. [ABSTRACT FROM AUTHOR]

A fully bio-based epoxy thermosetting network was prepared by curing a renewable luteolin-derived epoxy resin (DGELU) with a furan-derived hardener, 5, 5′-methylenedifurfurylamine (DFA). For comparison, a control sample was prepared by curing the petroleum-based commercial epoxy diglycidyl ether of bisphenol A (DGEBA) with a petroleum-based hardener, 4, 4′-diaminodiphenylmethane (DDM). The glass transition temperature (T g) was found to be 216 °C for the cured DGELU/DFA, which was 67 °C higher than that of the cured DGEBA/DDM. The storage modulus at 30 °C and the tensile strength of the cured DGELU/DFA were 82.5 % and 23.2 % higher than those of the cured DGEBA/DDM. The benzopyrone unit of the luteolin structure was conducive to exceptional charring, and the char yield for thermal decomposition in the nitrogen of the cured DGELU/DFA was 3.2-fold higher than that for the cured DGEBA/DDM. As expected, the cured DGELU/DFA displays a relatively high limiting oxygen index (LOI) of 38.0 % and a UL-94 V-0 classification, whereas the petroleum-based counterpart exhibited a much lower LOI of 24.0 % and no classification in the UL-94 test. An in-vitro cytotoxicity study indicated that the cured DGELU/DFA showed no cytotoxic effect against normal fibroblast cells after 24 and 72 h. Because of these fascinating features, the DGELU/DFA thermosetting network was deposited onto wood surfaces for evaluation as a flame-retardant coating. Compared with the wood treated using the cured DGEBA/DDM coating, wood coated with the cured DGELU/DFA showed a super fire-safe property that could lead to a 55.8 %, 12.4 %, and 11.5 % decrease in peak heat release rate (PHRR), total heat release (THR), and total smoke production (TSP), respectively. An anti-flammable, high strength and non-toxic bio-derived epoxy thermosetting network for highly safe epoxy coating applications has been developed. • A fully bio-based epoxy thermoset (DGELU/DFA) has been prepared from luteolin. • DGELU/DFA showed higher Tg and tensile strength than its petroleum-based counterpart. • DGELU/DFA displayed anti-flammability with a high LOI of 38.0 % and a UL-94 V-0 grade. • DGELU/DFA showed no cytotoxic effect against normal fibroblast cells. • DGELU/DFA is suitable as a flame-retardant and eco-friendly coating for wood. [ABSTRACT FROM AUTHOR]

Polyester fabric is ubiquitously applied for clothing, furniture and transportation, whereas its flammability with severe dripping often causes secondary hazards. Herein, it is highly imperative to impart excellent flame retardant to polyester fabric. In this work, a coating for polyester fabrics was prepared through a continuous dipping and ultraviolet (UV) curing process, which exhibited high-efficiency flame-retardant, anti-dripping and washing resistance. Firstly, the surface of polyester fabric was pretreated with plasma for providing more grafting sites of polyester fabric. Then, the flame retardant 6-((((2-(acryloyloxy) ethoxy) (oxo)(phenyl)phosphonio) oxy) methyl) dibenzo[c,e][1,2]oxaphosphinine 6-oxide (DPEA) and Tri(acryloyloxyethyl) phosphate (TAEP) were successfully synthesized and applied to the coating by UV-curing. In vertical burn test, the damage length of polyester with DPEA and TAEP (PET-D 3 /T 4.5) was reduced from 300 mm of pristine PET to 100 mm with no dripping. In the Thermogravimetric Analysis (TGA) test, the char residue of PET-D 3 /T 4.5 in nitrogen increased to 26.7 % compared with 9.7 % of pristine polyester. More specifically, the Peak Heat Release Rate (PHRR) and Total Heat Rate (THR) of PET-D 3 /T 4.5 decreased 43.3 % and 22.2 % in the Micro-scale Combustion Calorimetry (MCC) test, which reflected excellent thermal stability and flame retardant properties. In addition, the Limiting Oxygen Index (LOI) of PET-D 3 /T 4.5 only dripped from 24 % to 23.5 % after ten standard laundering cycles, indicating prominent water resistance. Remarkably, Thermogravimetric Analysis-Fourier transform infrared (TG-IR), Scanning Electron Microscope (SEM) and X-ray Photoelectron Spectroscopy (XPS) have been performed for investigating the mechanism of flame retardant. Thus, a strategy with convenience and economics is proposed, which is of gargantuan significance to the improvement of coating durability through plasma surface treatment and UV-curing. [Display omitted] • The improvement of coating durability through plasma surface treatment and UV-curing. • The damage length of coated polyester is reduced to 100 mm with no dripping. • The peak heat release rate and total heat rate of coated polyester is decreased by 43.3 % and 22.2 %. • The flame-retardant mechanism of different valence phosphorus in coating is studied. • A simple coating strategy for giving versatility to polyester fabric. [ABSTRACT FROM AUTHOR]

This work was intended to clarify if the dyeing treatment could modify the functional properties of white substrate as well as the surface finishing would alter the initial color of dyed textiles. Thus, in this work, a kind of surface coating was applied to modify the flame retardant and hydrophilic properties of both the undyed (white) and dyed polyamide 6.6 (PA6.6) textiles using some novel compounds like chitosan (CS), montmorillonite (MMT), sodium alginate (ALG) and phytic acid (PA) in a quadralayer (QL) or a hexalayer (HL) fashion. The obtained results revealed that the dyed fabric samples exhibited better flame retardancy and hydrophilicity compared to the undyed one; indicating the dyeing treatment contributed in improving the functional properties. For example, the 5HL-deposited dyed fabric sample (i.e., PA6.6-D-5HL) showed a maximum reduction in the peak heat release rate (pHRR) by 32% and the 7.5QL-deposited dyed fabric sample (i.e., PA6.6-D-7.5QL) brought a water contact angle (WCA) value of 0°. However, this kind of surface finishing caused a slight loss in depth of color for the dyed fabric samples. [Display omitted] • A kind of surface coating was developed onto the undyed and dyed PA6.6 textiles. • Dyed fabrics showed better flame retardant properties compared to the undyed one. • Dyed fabric with a 5HL deposition obtained a maximum reduction in pHRR by 32%. • A super-hydrophilic surface was realized, especially for the dyed fabrics. • The applied finishing slightly altered the depth of color of dyed fabrics. [ABSTRACT FROM AUTHOR]

In order to enhance the fire resistance of poly(methyl methacrylate) (PMMA), a new transparent flame-retardant coating was prepared by coating hyperbranched poly(urethane-phosphine oxide) (HPUPO) onto PMMA surface, which was synthesized from 4,4′-diphenylmethane diisocyanate (MDI) and trihydroxymethylphosphine oxide (THPO). The ratio of MDI to THPO was changed to prepare HPUPO with different structures. The HPUPO coatings show a strong adhesion of 5B grade to PMMA and all coated PMMA have a high transparency as pure PMMA. In cone calorimetry test, peak heat release rate (PHRR) of all HPUPO coated PMMA decrease very obviously. The PHRR and total heat release (THR) values of PMMA-0.8 (HPUPO coated PMMA with the ratio of MDI to THPO 1: 0.8) are reduced by 83.6% and 33.0% compared to those of pure PMMA. For PMMA-1.1 and PMMA-1.25, the heat, smoke and toxic gas release are all decreased effectively, which indicates improvement of fire safety of PMMA. The PHRR, THR, total smoke production (TSP) and CO yield (COY) of PMMA-1.1 are decrease by 83.3%, 11.0%, 27.6% and 34.8%, respectively. In the back temperature test, PMMA-0.95 and PMMA-1.1 have the lowest back temperature rise rates in HPUPO coated PMMA, and the back temperature are about 200 °C under the continuous burning of the alcohol lamp for 800 s. In summary, PMMA-1.1 shows excellent transparency, adhesion and fire safety. HPUPO coated PMMA is a promising fire safe PMMA material for practical application and HPUPO can be used as transparent flame retardant coating with tailorable properties. [Display omitted] • A transparent flame retardant coating for PMMAwas prepared with hyperbranched poly(urethane-phosphine oxide). • The HPUPO coatings show a strong adhesion and high transparency. • The HPUPO coatings can effectively improve the fire safety of PMMA. [ABSTRACT FROM AUTHOR]

• A hybrid coating was prepared from chitosan, melamine, urea, phytic acid and GO. • Improved flame retardancy and hydrophilicity of PA6.6 fabrics were realized. • Hybrid coating raised LOI value up to 25 % and stopped the melt dripping completely. • A maximum reduction in pHRR by 56 % was achieved with 5 BLs depositions. • Hybrid coatings could withstand against 10 home laundering cycles. The layer by layer (LBL) deposition of chitosan/melamine/urea (CS/ME/UREA) and phytic acid (PA) onto the acrylic acid (AA) grafted Polyamide 6.6 (PA6.6) fabrics including a pad-dry-cure treatment with chitosan/graphene oxide (CS/GO) nanocomposites were considered to improve the hydrophilicity and durable flame retardancy. Obtained results indicated that these hybrid coatings could significantly improve the flame retardancy as the limiting oxygen index (LOI) value reached up to 25 % from 18.5 % and could completely stop the melt dripping where the fabric sample with two bilayers deposition and simultaneously treated with CS/GO nanocomposite (PA6.6-g-AA-2BL-CS/GO) achieved a V-1 rating. A 2BLs deposited hybrid coating (i.e., PA6.6-g-AA-2BL-CS/GO) could decrease the peak heat release rate (pHRR) by 47.1 %; whereas a maximum reduction of pHRR by about 56 % was achieved for 5BLs deposition. Moreover, a considerable improvement in thermal stability and char yield% were also realized in the thermogravimetric analysis (TGA) test. Furthermore, the as-prepared hybrid coatings imparted better hydrophilicity as a 2BLs deposition along with pad-dry-cure treatment by CS/GO could boost up the hydrophilicity of the treated fabrics further compared to the only 2BLs deposited fabric sample. In addition, the application of CS/GO nanocomposite could improve the stability of this coating and able to stop the dripping tendency even after 10 laundering cycles as well. [ABSTRACT FROM AUTHOR]