Effect of Ulexite on Mechanical, Thermal, and Flame Properties of Halogen-Free Fire Retardant Polypropylene (original) (raw)

Influence of mica mineral on flame retardancy and mechanical properties of intumescent flame retardant polypropylene composites

Open Chemistry, 2021

In many plastic applications, improvement of the flame retardancy is a very significant topic. Polypropylene (PP) is used in many applications such as housing industry due to its cost performance efficiency. Enhancement of flame retardancy properties of PP is necessary in many applications. In this study, the investigation focuses on the synergistic effect of mica mineral and IFR in enhancing the flame retardancy properties of PP in order to achieve cost competitive solution, so as to provide that different/various ratios of IFR and mica mineral were added into PP to compose 30 wt% of the total mass of the polymeric compounds. The synergistic effect of mica mineral with IFR in PP was investigated by limiting oxygen index (LOI), glow wire test (GWT), UL-94 test, thermal gravimetric analyses (TGA), and mechanical tests. The results from LOI, UL 94, and GWT tests indicated that mica added to PP/IFR compound has a synergistic flame retardancy effects with the IFR system. When the conten...

Flame Retardant Polypropylene Composites with Low Densities

Materials, 2019

Polypropylene (PP) is currently widely used in areas requiring lightweight materials because of its low density. Due to the intrinsic flammability, the application of PP is restricted in many conditions. Aluminum trihydroxide (ATH) is reported as a practical flame retardant for PP, but the addition of ATH often diminishes the lightweight advantage of PP. Therefore, in this work, glass bubbles (GB) and octacedylamine-modified zirconium phosphate (mZrP) are introduced into the PP/ATH composite in order to lower the material density and simultaneously maintain/enhance the flame retardancy. A series of PP composites have been prepared to explore the formulation which can endow the composite with balanced flame retardancy, good mechanical properties, and low density. The morphology, thermal stability, flame retardancy, and mechanical properties of the composites were characterized. The results indicated the addition of GB could reduce the density, but decreased the flame retardancy of PP composites at the same time. To overcome this defect, ATH and mZrP with synergetic effect of flame retardancy were added into the composite. The dosage of each additive was optimized for achieving a balance of flame retardancy, good mechanical properties, and density. With 47 wt % ATH, 10 wt % GB, and 3 wt % mZrP, the peak heat release rate (pHRR) and total smoke production (TSP) of the composite PP-4 were reduced by 91% and 78%, respectively. At the same time, increased impact strength was achieved compared with neat PP and the composite with ATH only. Maintaining the flame retardancy and mechanical properties, the density of composite PP-4 (1.27 g•cm −3) is lower than that with ATH only (PP-1, 1.46 g•cm −3). Through this research, we hope to provide an efficient approach to designing flame retardant polypropylene (PP) composites with low density.

An efficient approach to improving fire retardancy and smoke suppression for intumescent flame‐retardant polypropylene composites via incorporating organo‐modified sepiolite

Fire and Materials, 2019

In this work, an efficient approach to improving the fire retardancy and smoke suppression for intumescent flame-retardant polypropylene (PP) composites is developed via incorporating functionalized sepiolite (organo-modified sepiolite [ONSep]). The PP composites with different amounts of intumescent flame retardants and ONSep were prepared by melt compounding. The morphology, thermal behavior, fire retardancy, smoke suppression, and mechanical property of flame-retardant PP composites were studied. The results indicate an appropriate amount of ONSep in the flame-retardant PP composites can increase thermal degradation temperature and char formation as well as a reduction of the peak heat release rate and total heat release; moreover, the addition of ONSep significantly decreases the CO production, total smoke production, smoke production rate, and smoke temperature. Simultaneously, the impact strength of intumescent flame-retardant PP composite is also maintained by introducing an appropriate amount of ONSep as compared with that without ONSep. KEYWORDS flame/fire retardancy, mechanical properties, nanoparticles, polymer-matrix composites 1 | INTRODUCTION Polypropylene (PP) is widely used in a variety of applications, including transportation, construction, electronic appliances, and general household materials for its excellent physical and mechanical properties, low density, ease of processing, good chemical resistance, etc. 1,2 Nevertheless, the flammability characteristics of PP is one of the main drawbacks limiting its wide application. 3,4 In order to expand its application, significant work has been performed to improve fire safety of PP. Halogen-containing flame retardants have been widely applied to PP because of their high efficiency as radical scavengers during combustion, even in low loading levels. However, this kind of additive releases significant amounts of toxic gases and corrosive smoke during combustion. 5,6 Thus, advanced halogen-free and low-smoke flame retardant systems are one of the most popular topics in current polymer materials research and development, such as metal hydroxides and intumescent flame retardants (IFRs). Metal hydroxides like aluminum trihydroxide (ATH) or magnesium dihydroxide (MDH) can decompose during heating, releasing water and forming a char layer that reduces the temperature and decomposition rate of the polymer substrate. 7,8 However, very high concentrations greater than 50 wt% of these additives must be used to achieve good flame retardancy, and the physical and mechanical properties of PP are negatively impacted. Recently, IFR is considered to be one of the most promising flame retardants to replace halogen-containing flame retardants because of its environmentally friendly, high-efficiency, anti-dripping, and low

A study on various fire retardant additives used for fire reinforced polymeric composites

AIP Conference Proceedings , 2022

The growing environmental awareness and natural resources scarcity various fully biodegradable polymer systems development and utilization initiates poly lactic acid (PLA) and copolymers biodegradable polymer, extensive attention as they biodegradability, numerous renewable sources, and excellent mechanical and thermal properties like advantages other polyester resins like PLA inherent chemical composition and molecular structures due to very poor fire resistance the aviation and electrical industry PLAs widespread use low thermal resistance, combustion and drip hampered flame retardant modification essential Combustion-type flame retardants polymer by physical means incorporated materials production convenient industry widely in used. Flame retardants certain chemical compounds polymers paralytic reactions slow or inhibit or combustion oxidative reactions They mainly halogen, phosphorus and metal hydroxides containing compounds Halogen flame retardant drawbacks metal components highlight ability combustion during hydrogen formed toxicity and some governments or organizations halogen controlled flame retardants use restrict proposed halogen-free flame-retardant additives indomethacin flame retardant (IFR) considerable attention and polypropylene (PP) and polyethylene (PE) such as polymers used their low smoke, no toxicity, and halogen absence benefits. and corrosive gas production In general an IFR system three basic components char-forming agent carbonization catalyst, and a blowing agent combustion during IFR multi-cellular structure combustible layer a physical that acts barrier gas and compressed between heat and mass transfer reducing reducing the burning melt in thermoplastic flame-retardant conversion is a particular problem. Drops melting burning surface area increase fire intensity increase faster fire spread viscosity Melting coal formation strong impact PLA, polyethylene terephthalate (PET), and poly butylenes succinct (PBS) like Linear polymers branched or thermo set polymers compared low melt viscosity burning test during serious melt dripping layered silicates thermal stability improve reduce filler concentration flammability low investigations found.

Effect of Tris(1,3-Dichloroisopropyl) Phosphate as Flame Retardant on Mechanical Properties and Fire Resistivity of PU Composites

Al-Nahrain Journal of Science

Palm oil based polyurethane composites that are reinforced with Tris(1,3-dichloroisopropyl) phosphate TDCPP which function as flame retardants (FR) at different proportions of 3, 6 and 9% were synthesized. The polyurethane composite's influence on the mechanical (tensile strength, impact and flexural limits and modulus) and thermal characteristics (fire test) of the polyurethane composites were examined. Increased loading of TCPP resulted in increased hardness (up to 39%) which translates to a marginal increase in Shore D hardness as the TDCPP content increases. With higher TDCPP loading, the impact and flexural capabilities decreased because of the fragile interfacial bonding between the TDCPP and PU matrix. Loading of 3%, 6% and 9% of TDCPP resulted in the decrease of impact strength by 25%, 24% and 23% respectively. Lowest flexural ability (at a reduction of 21%) was exhibited with the highest amount of TDCPP loading (9%) and the modulus had decreased by 23%. When the percentage of TDCPP loading increased, this resulted in a lower heat of combustion of the composites which manifested in the form of lower burning rate from 5.4 mm/s to 2.7 mm/s in the fire test operated.

Effect of Fillers on the Fire Retardant Properties of Intumescent Polypropylene Compounds

Polymers and Polymer Composites, 2008

The effects of fillers, including ammonium polyphosphate (APP), aluminium trihydrate (ATH) and talc, and the effect of polyethylene vinyl acetate (EVA) as an interfacial agent, were investigated on the flame retardant properties of intumescent polypropylene (PP), by using mechanical testing, to measure the tensile and Izod impact strengths, thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and the limiting oxygen index (LOI) test method. SEM studies showed that the dispersion of flame retardant particles in the PP matrix improved with the use of EVA. Tensile strength decreased but elongation at break and impact resistance of PP/APP/EVA and PP/ATH/EVA composites increased by using 10 wt.% of EVA. Using 12 wt.% of talc in PP/APP/PA-6/EVA led to increasing impact resistance and decreasing tensile strength and elongation at break of the composite. EVA prevented the exudation of additives to the composite surface, and consequently the fire retardant properties of the c...

Key Role of Reinforcing Structures in the Flame Retardant Performance of Self-Reinforced Polypropylene Composites

Polymers, 2016

The flame retardant synergism between highly stretched polymer fibres and intumescent flame retardant systems was investigated in self-reinforced polypropylene composites. It was found that the structure of reinforcement, such as degree of molecular orientation, fibre alignment and weave type, has a particular effect on the fire performance of the intumescent system. As little as 7.2 wt % additive content, one third of the amount needed in non-reinforced polypropylene matrix, was sufficient to reach a UL-94 V-0 rating. The best result was found in self-reinforced polypropylene composites reinforced with unidirectional fibres. In addition to the fire retardant performance, the mechanical properties were also evaluated. The maximum was found at optimal consolidation temperature, while the flame retardant additive in the matrix did not influence the mechanical performance up to the investigated 13 wt % concentration.

Effects of Flame Retardants Additives on the Properties of Low-Density Polyethylene

International Journal of Engineering Technology and Sciences, 2018

Low-density polyethylene (LDPE) has many unique properties such as lightweight and high chemical resistance. Unfortunately, it burns rapidly when it is exposed to a flame which limits its applications especially when flame resistance is to be considered. Different percentages of magnesium hydroxide and decabromide diphenyl ether (3.0, 5.0, 7.0, and 9.0 wt.%) were mixed with LDPE using a two-roll mill machine at 1600C for 2 minutes. Then, the tensile and flame retardancy tests samples were prepared by an injection molding process using an industrial plastic machine at 1600C. Flammability, rheological, tensile and thermal properties of the produced samples were tested using a flammability test apparatus, a melt flow index machine, a universal testing machine, and a differential scanning calorimeter, respectively. It was observed that the flame resistance of LDPE was improved with the addition of both flame retardants up to 7.0 wt.%, then it was reduced when 9.0 wt.% of flame retardant...

Analysis of the Fire Behavior of Polymers (PP, PA 6 and PE-LD) and Their Improvement Using Various Flame Retardants

Materials, 2020

The fire behavior of polymers is examined primarily with the time-dependent heat release rate (HRR) measured with a cone calorimeter. The HRR is used to examine the fire behavior of materials with and without flame retardants, especially Polypropylene (PP-Copo) and Polyethylene (PE-LD). Polypropylene is stored for up to 99 days under normal conditions and the heat release rate shows especially changes about 100 s after irradiation with cone calorimeter, which may be caused by aging effects. The effect of crosslinking to the burning behavior of PP was examined too. Polyamides (PA 6) are irradiated with a radiation intensity of 25 kW/m2 to 95 kW/m2 and fire-related principles between radiation intensity and time to ignition can be derived from the measurement results. In order to comprehensively investigate the fire behavior of PP (also with flame retardant additives), the samples were also exposed to a flame, according to UL 94 with small power (50 W) and is inflamed with the power o...