Hierarchical Ti3C2Tx@BPA@PCL for flexible polyurethane foam capable of anti-compression, self-extinguishing and flame-retardant.

In this study, three-dimensional flower-like Ni-MOFs were fabricated and successfully functionalized on multi-terminal lamellar MXene (Ti 3 C 2 T x ) by solvothermal method, and their flame retardant application in thermoplastic polyurethanes (TPU) was investigated. As expected, the addition of Ni-MOF@Ti 3 C 2 T x can improve the flame retardancy and smoke suppression properties of TPU. The heat release rate, the smoke release rate, total smoke production, CO and CO 2 release of the composite with only 1wt%MOF@Ti 3 C 2 T x were significantly reduced by 15%, 44%, 26%, 18%, and 8%, respectively. Furthermore, the carbon residues of TPU/Ni-MOF@Ti 3 C 2 T x composites were about 2-5 times that of pure TPU, indicating that the Ni-MOF@Ti 3 C 2 T x can inhibit the thermal degradation of TPU. The mechanism illustrated that the excellent fire safety properties of TPU/Ni-MOF@Ti 3 C 2 T x composites are due to the physical barrier, catalytical carbonization, and gas-phase flame retardant of Ni-MOF@Ti 3 C 2 T x . In this work, the dispersity, thermal stability, and flame retardancy of MXene were improved due to the modification of MXene with Ni-MOF by chemical bonding and physical adsorption, which can broaden the range of applications of MOFs. 

Interface assembly of flower-like Ni-MOF functional MXene towards the fire safety of thermoplastic polyurethanes

In this study, a phosphorus-containing bio-based monomer (MBDPP) was first synthesized from renewable magnolol, and subsequently photo-cured with tri-thiol (TPTMP) or tetra-thiol (PETMP) monomers via thiol–ene polymerization. The synthesized MBDPP/TPTMP and MBDPP/PETMP membranes exhibited high char residues at 700 °C in the TGA tests, which were 19.8 wt% and 24.2 wt% for nitrogen while 16.5 wt% and 20.2 wt% for air, respectively, indicating superior charring capacity of both membranes. DMA results indicated that both the higher stiffness and the Tg of the cured MBDPP/PETMP membrane was ascribed to its higher cross-linking density than that of the cured MBDPP/TPTMP owing to the tetra-functional groups of PETMP. In the open flame test, both MBDPP/TPTMP and MBDPP/PETMP membranes self-extinguished immediately when removing the flame source, manifesting excellent intrinsic anti-flammability. The cone calorimeter results further demonstrated that MBDPP/TPTMP and MBDPP/PETMP membranes showed lower PHRR (419 and 388 kW/m2, respectively) and THR (41.38 and 38.98 MJ/m2, respectively) values than most of the thiol-ene photo-polymerized counterparts previously reported. The excellent anti-flammability of MBDPP/TPTMP and MBDPP/PETMP membranes originated from the formation of expandable char residues that played an efficient role in hampering the transfer of flammable pyrolysis products to flame zone as well as insulating the heat irradiation during combustion. Additionally, both MBDPP/TPTMP and MBDPP/PETMP membranes showed excellent transparency (transmittance >85% in the visible region) and flexibility (breaking elongation around 40%). Taking the intrinsic anti-flammability, exceptional transparency and high flexibility into account, the MBDPP/TPTMP and MBDPP/PETMP systems are suitable as intumescent flame retardant coating materials. 

Magnolol-derived thiol-ene photo-polymerized membranes with intrinsic anti-flammability and high transparency

On the thermal and mechanical performance of Polycarbonate / Titanium Nitride nanocomposites in Material Extrusion Additive Manufacturing

A bio-based intumescent flame retardant with biomolecules functionalized ammonium polyphosphate enables polylactic acid with excellent flame retardancy

Polycarbonate (PC) is highly attractive for applications in high-speed railways and airplanes as engineering materials, but suffers from high fire hazards with severe melting dripping during burning. To overcome the challenge, highly effective flame retardants, such as sulfonate derivatives and silicon-based compounds have been developed. Unfortunately, there is still lacking of a systematic method to evaluate the fire risk of these flame-retardant PC composites. Herein, we propose a comprehensive and innovative approach to assess the fire safety of flame-retardant PC composites containing potassium perfluorobutane sulfonate (PPFBS) and a silicon-based flame retardant (PSR) through combining numerous combustion parameters obtained from different measurements. The pyrolysis and combustion characteristics of PC/PPFBS and PC/PSR were studied in detail and revealed that PPFBS and PSR could effectively reduce the activation energy of PC. PSR is effective at reducing the heat and smoke release due to the formation of a Si–C protective layer during combustion. In contrast, PPFBS has no obvious suppression effect on smoke generation, and even shows a combustion-supporting effect under high radiation flux. Based on the analytic hierarchy process (AHP), a comprehensive evaluation model has been established to achieve an objective and comprehensive evaluation of the fire hazards of PC and its composites. This works provides a universal guidance for evaluating fire hazards of flame-retardant polymer composite. 

Zhu Yulu

Papers

High-performance flame-retardant polycarbonate composites: Mechanisms investigation and fire-safety evaluation systems establishment