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The intumescent flame retardant (IFR) technique is an alternative to halogen-based flame retardants for reducing fire hazards in polymers. However, IFR has drawbacks like unsatisfactory flame-retardant efficiency and high loading requirements. In this study, MIL-125 (Ti-based metal–organic framework) is added to ABS/IFR composites to improve flame retardancy and reduce smoke emissions. Thermogravimetric analysis (TGA) results indicate that combining ammonium polyphosphate (APP) and expandable graphite (EG) increases charred residue and slows mass loss compared with the original ABS resin. The ABS/IFR/MIL-125 system stabilizes the char layer, serving as a protective shield against combustible gases during combustion. Additionally, MIL-125 enhances performance in microscale combustion calorimetry (MCC) flammability testing. In fire tests (UL-94, limiting oxygen index (LOI), and cone calorimeter), the ABS/IFR/MIL-125 system achieves a UL-94 V0 rating and the highest LOI value of 31.5% ± 0.1%. Peak heat lease rate (PHRR) values in the cone calorimeter are reduced by 72% with 20 wt.% of additives, and smoke production decreases by 53% compared with neat ABS. These results demonstrate the efficient synergistic effects of MIL-125 and IFR additives in improving the formation and stability of the intumescent char layer, thereby protecting ABS from intense burning. [ABSTRACT FROM AUTHOR]

Ozone, widely recognized as an environmentally friendly gas, is extensively used in various textile industry applications. These include pre-treatment processes like bleaching and desizing, as well as creating pattern and vintage effects, wastewater clarification, and surface modification. This study focuses on ozone as a novel solution to a specific challenge: addressing the reduction in flame retardancy properties experienced by flame-retardant (FR) polyester fabrics during post-treatment processes in the production line. Experimentation involved subjecting the fabrics to ozonation and exploring different combinations of ozone flow rates and treatment durations. Mechanical and functional properties of the fabrics were examined, with flammability tested according to International Maritime Organization (IMO) standards. Notably, treatment with a 5 L/min ozone flow rate, a 7.01 g/h ozone concentration ratio, and a duration of 10 min showed significant improvements in IMO values, ensuring compliance with required standards. Furthermore, treated samples underwent comprehensive tests for fastness and strength, yielding results within acceptable ranges. Fourier-transform infrared (FT-IR) and thermogravimetric analysis (TGA) measurements were conducted to evaluate the impact of ozonation. FT-IR results indicated that the presence of C-H groups associated with dyestuff contributed to decreased flame retardancy in the original fabric post-dyeing. However, these groups were effectively eliminated through ozonation, thereby enhancing the fabric's flame retardancy. [ABSTRACT FROM AUTHOR]

High-density polyethylene (HDPE) is a commonly used material for cable sheathing, which is a flammable material. To ensure the safe transportation of electrical energy, it is necessary to enhance the flame-retardant properties of HDPE materials. In this work, ammonium polyphosphate (APP) with lignin (Lig) is used as an intumescent flame retardant, and the flame retardant properties of APP/Lig for HDPE with different ratios are analyzed. It is found that with 3/1 ratio of APP and Lig under 30 wt%, the best flame-retardant performance is achieved. To further improve its properties, chemical modification of Lig with hexachlorocyclotriphosphazene (HCCP) is conducted to introduce nitrogen and phosphorus, obtaining NP-Lig. Flame retardant, mechanical and electrical properties are tested for the prepared material. The flame retardant tests show that the LOI of HDPE is increased from 23.8 to 28.2 by the addition of APP/NP-Lig, compared to that of APP/Lig. Mechanical tests show that replacing Lig with NP-Lig slightly increases the tensile strength and elongation at break of HDPE. Electrical tests show that APP/NP-Lig flame retardant maintains the electrical properties of HDPE under the industry standards. • Ammonium polyphosphate/lignin significantly improves the flame retardancy of HDPE materials. • NP-lig can further improve the composite's flame retardant properties. • HDPE/APP/NP-Lig meets the requirements of cable sheathing in flame retardant, mechanical, and electrical properties. [ABSTRACT FROM AUTHOR]

To solve the non-renewable and flammability of traditional epoxy composites, a new type of intrinsic flame-retardant epoxy (VH/GF) composite was fabricated from vanillin-based epoxy resin (VH) and glass fibre (GF). The T 5% of VH/GF was higher than that of DGEBA/GF, and CY 800 of VH/GF reached above 84 wt%. VH/GF obtained a limiting oxygen index as high as above 90 % and passed UL-94 V-0 rating. Compared with DGEBA/GF, the total heat release, total smoke production, maximal smoke density of VH/GF reduced by more than 72 %, 91 % and 81 %, respectively. The physical barrier of glass fibre and excellent char formation ability of VH endowed VH/GF composite with good condensed phase flame-retardant effect. When the mass ratio of matrix and glass fibre was 5:5, the storage modulus and glass transition temperature of VH/GF were 6.34 GPa and 205 °C, and its tensile strength and elongation at break were 348.36 MPa and 4.01 %. This work provides new research insights for bio-based epoxy resin in high-performance fire safety composites. • Intrinsic flame-retardant epoxy composites were fabricated by hot pressing forming of prepreg. • Flame-retardant epoxy composites obtained a limiting oxygen index as high as above 90 % and passed UL-94 V-0 rating. • The storage modulus and glass transition temperature of epoxy composite were respectively 6.34 GPa and 205 °C. • Synergistic effect of glass fibre and epoxy matrix endowed composite with good flame retardancy and mechanical properties. [ABSTRACT FROM AUTHOR]