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Although cotton is the most common polymer in daily life, its limited use is due to its propensity to catch fire. To solve this issue, we developed an innovative flame‐retardant aluminum phosphate‐supported, chitosan‐linked expandable graphite composite (CAlPEG). The CAlPEG was synthesized by the reaction of natural graphite, aluminum phosphate, and chitosan biopolymer in a one‐pot method. When CAlPEG was coated with cotton fabric and exposed to continuous flame, the fabric did not catch fire up to 760 s, whereas only expandable graphite (EG), aluminum phosphate (AIP), and CS, coated cotton fabric burned within 20 s. Flame‐retardant proficiency of CAlPEG‐coated cloth was confirmed by flame tests such as a limiting oxygen index (LOI) and vertical flammability test. The blank cotton has 17% LOI and is completely burnt out. On the other hand, the as‐prepared composite has a 43% LOI rating, which denotes a high level of flame retardancy. The VFT test result showed the formation of a 3 cm char, which confirms the flame‐retardant material possesses self‐extinguishing qualities. The article develops a new method for utilizing bioresources such as chitosan and offers fresh perspectives on the environmentally friendly synthesis of phosphorylated EG‐linked chitosan on the AlPO4 matrix. [ABSTRACT FROM AUTHOR]

Graphene-composites, capable of inhibiting bacterial growth which is also bio-compatible with human cells have been highly sought after. Here we report for the first time the preparation of new graphene-iodine nano-composites via electrostatic interactions between positively charged graphene derivatives and triiodide anions. The resulting composites were characterized by X-ray photoemission spectroscopy, UV-spectroscopy, Raman spectroscopy and Scanning electron microscopy. The antibacterial potential of these graphene-iodine composites against Klebsiella pneumonia, Pseudomonas aeruginosa, Proteus mirobilis, Staphylococcus aureus, and E. coli was investigated. In addition, the cytotoxicity of the nanocomposite with human cells [human white blood cells (WBC), HeLa, MDA-MB-231, Fibroblast (primary human keratinocyte) and Keratinocyte (immortalized fibroblast)], was assessed. DGO (Double-oxidizes graphene oxide) was prepared by the additional oxidation of GO (graphene oxide). This generates more oxygen containing functional groups that can readily trap more H(+), thus generating a positively charged surface area under highly acidic conditions. This step allowed bonding with a greater number of anionic triiodides and generated the most potent antibacterial agent among graphene-iodine and as-made povidone-iodine (PVP-I) composites also exhibited nontoxic to human cells culture. Thus, these nano-composites can be used to inhibit the growth of various bacterial species. Importantly, they are also very low-cytotoxic to human cells culture.

Flame retardancy in various materials is becoming an increasingly important performance feature. In the textile industries, fire‐related problems have become an important concern over the decade. Herein, the polyvinyl alcohol (PVA) and graphene‐supported material were functionalized with trimethyl phosphate (TMP) for the synthesis of flame retardant (FR) composite material [graphene polymer functionalized trimethyl phosphate (GPTMP)] in the aqueous medium, which improves the stability of cotton fabric against flame. Graphene and PVA fabricated with phosphorus functional groups make the fabric more comfortable against fire and help to avoid further spreading of fire. The composite‐coated fabric sustains for a long time on continuous flame with maintaining its initial shape and size. The GPTMP‐coated fabric shows flame retardancy for up to 540 s on constant flame exposure, whereas control samples such as PVA‐, graphene oxide‐, and TMP‐coated fabrics resist for up to 15, 20, and 14 s, respectively. The limiting oxygen index (LOI) and vertical flammability test (VFT) for synthesized composites were performed to confirm and support the flame retardancy property of GPTMP. The GPTMP shows the 35% LOI value and forms the char length of 2.6 cm during VFT. This work provides a simple and eco‐friendly method to obtain novel GPTMP, which has a high potential as a FR for different fabrics, including cotton. [ABSTRACT FROM AUTHOR]

Synthetic dyes used in the textile sector have adverse impacts on the environment and human health. Natural dyes are thus a suitable alternative for sustainable textile manufacturing and colouration; however, preparing highly stable dyes on textile fabric remains challenging. In this study, we prepared a copper and 2‐methyl‐8‐hydroxyquinoline (2‐Me‐8‐HQ) functionalized graphene oxide (GO) (CHG) ternary composite as the mordant to enhance the stability and colour strength of naturally extracted turmeric (Tu) and tea (Te) dyes. To evaluate the effect of the CHG composite, it was mixed with Tu and Te dyes to obtain CHG‐functionalized turmeric and tea dyes (TuCHG and TeCHG), respectively. TuCHG and TeCHG exhibited superior colourfastness, wash fastness, and rub fastness, compared with only Tu and Te dyed cotton fabrics. The cytotoxicity of TuCHG and TeCHG was studied in the presence of human keratinocytes HacaT cells. The TuCHG and TeCHG dyes exhibited no cytotoxicity and good antibacterial properties. The proposed method is safe, cost‐effective, and sustainable for applying natural dyes with enhanced stability on cotton fabrics. [ABSTRACT FROM AUTHOR]