Flame Retardant Master Batch Research Articles

Towards a more circular economy for WEEE plastics – Part A: Development of innovative recycling strategies

This two paper series describes a method to develop and evaluate innovative recycling strategies for WEEE plastics. Part A presents a SWOT analysis of a new dismantling based recycling process of plastic components and the integration in an existing post-shredder separation recycling facility. Subsequently, recycling strategies are developed and the economic potential is evaluated. Part B investigates the technical feasibility of the recycling strategies.As a case study the dismantling of LCD TV plastic back cover housings is taken. First, the advantages and disadvantages of the new process and the main external factors based on the market for recycled plastics and the waste material input are discussed on industrial level. Subsequently, five recycling strategies are developed: Strategy (1) produces recycled granulates with the dismantling process for direct re-application in electronic products, strategy (2) recycles plastics for the use as carrier materials for flame retardant masterbatches, strategy (3) blends the recycled plastic with post-shredder recyclates for material upgrading, strategy (4) recycles the plastics with the post-shredder process and strategy (5) thermally treats plastics. Finally, the economic evaluation shows that the special engineering plastics used for LCD TV back covers have very high virgin prices up to 5 € per kg. The implementation of the new process indicates a significant potential for value recovery based on plastics that would otherwise be incinerated or downcycled.

Desarrollo de compuestos XLPE con retardantes de llama de baja toxicidad para aislamiento de cables

Se desarrollaron nueve formulaciones de un masterbatch retardante a la llama de bajo impacto medioambiental y se evaluó la influencia de su incorporación en un polietileno lineal de baja densidad, injertado con un agente de entrecruzamiento viniltrimetoxisilano, para su posterior reticulación con el fin de obtener un polietileno entrecruzado con retardancia a la llama. Los masterbatch retardantes a la llama se prepararon a partir del uso de N, N-etilen bis(tetrabromoftalamida), mezclado con: trióxido de antimonio, borato de zinc, polietileno lineal de baja densidad, agente de dispersión y cera polietilenica, variando el N,N-etilen bis(tetrabromoftalamida) (36, 42 y 45 %) y el agente de dispersión (0.50, 1.25 y 2.00 %), mientras se mantuvo constante el resto de componentes. Posteriormente, los nueve masterbatch desarrollados se mezclaron con el polietileno lineal de baja densidad injertado para la producción de nueve compuestos de polietileno entrecruzado retardante de lama que luego se conformaron en forma de placas y aislamiento de cable 14 AWG para su caracterización fisicoquímica. Se encontró que el nivel empleado tanto en las cargas (N,N-etilen bis-tetrabromoftalamida, trióxido de antimonio y borato de zinc) como en el agente de dispersión condicionaron el nivel de entrecruzamiento estimado a partir del contenido de gel, las características de flujo y el comportamiento frente a la llama del material; siendo favorecidas las primeras dos propiedades con el incremento del agente de dispersión, en tanto que la última se vio mejorada con el aumento en la proporción de las cargas usadas. De igual manera, la evaluación de un compuesto de polietileno entrecruzado retardante a la llama fabricado con un masterbatch retardante a la llama comercial, tomado como referencia, evidenció que algunas de las formulaciones trabajadas en esta investigación son susceptibles de ser empleadas para el aislamiento de cables eléctricos.

Novel Intumescent Flame Retardant Masterbatch Prepared through Different Processes and Its Application in EPDM/PP Thermoplastic Elastomer: Thermal Stability, Flame Retardancy, and Mechanical Properties.

In this work, the ethylene-propylene-diene monomer/polypropylene (EPDM/PP) thermoplastic elastomer filled with intumescent flame retardants (IFR) is fabricated by melting blend. The IFR are constituted with melamine phosphate-pentaerythritol (MP/PER) by compounding and reactive extruding, respectively. The effects of two kinds of MP/PER with different contents on the thermal stability, flame retardancy, and mechanical properties of materials are investigated by Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), limiting oxygen index (LOI), UL-94, cone calorimeter test (CCT), and scanning electron microscopy (SEM). FTIR results show that the reactive extruded MP/PER partly generates melamine pyrophosphate (MPP) compared with compound masterbatches. TGA data indicate that the best thermal stability is achieved when the molar ratio of MP/PER reaches 1.8. All the reactive samples show a higher flame retardancy than compound ones. The CCT results also exhibit the same trend as above in heat release and smoke production rate. The EPDM/PP composites filled with 30 and 35% reactive MP/PER exhibit the improved flame retardancy but become stiffer and more brittle. SEM photos display that better dispersion and smaller particle size are obtained for reactive samples.

Effect of Organo‐Modified Nanosepiolite on Fire Behaviors and Mechanical Performance of Polypropylene Composites

AbstractThe objective of the study was to investigate the effect of the organo‐modified nanosepiolite (ONSep) on improving the fire safety of polypropylene (PP). The composites based on PP, flame retardant master batch (MB‐FR, 25 wt% PP+50 wt% decabromodiphenyl ether (DBDPE)+25% antimony trioxide (ATO)) and ONSep were prepared via melt blending. The results of the limiting oxygen index (LOI) and vertical burning rating (UL‐94) test indicated that PP/40 wt% MB composites had no rating with seriously dripping phenomenon, while the LOI value was only 22.5. However, as 4 wt% ONSep was added in PP/40 wt% MB composites, the composites achieved UL94 V‐0 rating and the LOI value was 24.3. In comparison, PP/50 wt% MB composites could not reach the V‐0 rating either. The TGA results revealed that the addition of ONSep enhanced the thermal stability of the PP/MB‐FR composites. The cone calorimeter results indicated that the heat release rate, average mass loss rate, smoke production rate and smoke temperature of the PP/40 wt% MB‐FR/4 wt% ONSep composites decreased in comparison with those of PP/40 wt% MB‐FR composites. Simultaneously, the Young modulus and impact strength were also much better improved with the increase of ONSep loading. Therefore, the synergistic flame retardancy of ONSep in PP/MB‐FR matrix significantly containing a halogen based flame retardant (DBDPE) significantly improved the fire safety and mechanical properties of the composites, and allowed to decrease the total amount of brominated fire retardants.

Tosaf presents a new range of flame retardant masterbatches for corrugated pipes

Israel's additives, masterbatches and compounding firm Tosaf Compounds has launched a new line of ‘green’ masterbatch products optimized for the production of corrugated pipes to be used as conductors for electrical cables in construction. Such conductors have to meet the European Flame Retardant (FR) Standard IEC 61386-1.

Gabriel-Chemie unveils new flame retardant, blowing agent and lubricant masterbatches

Austria's Gabriel-Chemie GmbH has introduced new halogen-free flame retardant masterbatches for both polyethylene (PE) and polypropylene (PP), alongside a blowing agent product for polylactic acid (PLA) applications and a lubricant masterbatch for PP-based wood-plastic composites. The products received their debut at the recent Fakuma trade fair in Friedrichshafen, where the company also revealed the latest edition of its colour trend guide.

Effect of an Ultrahigh Rubber ABS Impact Modifier Resin on Mechanical Properties of Intumescent Flame-Retardant ABS Composites

The effect of an ultrahigh rubber acrylonitrile-butadiene-styrene (ABS) impact modifier resin (UHR-ABS) on the mechanical properties of an intumescent flame-retardant ABS composite was characterized. Samples were obtained by compounding ABS and an intumescent flame-retardant master batch that was prepared using an intumescent flame-retardant composite (IFRC) with ABS and/or UHR-ABS as well as by direct compounding IFRC, UHR-ABS, and ABS. The incorporation of UHR-ABS resulted in reduction in the storage modulus, damping behavior and glass transition temperature, as evidenced by dynamic mechanical analysis. With increasing mass fraction of the UHR-ABS, the tensile strength and the flexural strength decreased gradually, and the notched impact strength increased, but the increase was more significant for compounding IFRC, UHR-ABS, and ABS than for compounding ABS and IFRC master batches. SEM micrographs of the fresh fracture surface of the composites were used to estimate the mechanism of the increased notched impact strength owing to the incorporation of UHR-ABS.

Solid State Shear Milling to Prepare Magnesium Hydroxide Flame-Retardant Polyamide 6 with High Performance

A novel processing method, that is, solid state shear milling (S3M), was adopted to compound high loading inorganic flame-retardant magnesium hydroxide with polyamide 6 by using our self-designed pan-mill equipment. S3M can effectively pulverize PA6, increase the interfacial interaction of the resin and magnesium hydroxide, and achieve their even blending, thus effectively controlling the state of the dispersion phase in solid state. With the co-milled composite powder as flame retardant master batch filled in original PA6 pellets, it can greatly improve the compatibility of the system, modify the distribution process of magnesium hydroxide, and decrease the dispersion phase size in the following melt processing. As a result, S3M technology can remarkably increase the melt flowability of the composite materials, and obtain obviously enhanced flame retardance and mechanical performance, thus providing an effective solution to the poor processibility and deteriorated performance of magnesium hydroxide flame-retardant PA6 obtained through direct melt processing.

Preparation of High Loading Magnesium Hydroxide Flame Retardant Polypropylene by Solid State Shear Milling

Due to high loading level and poor compatibility, magnesium hydroxide (MH) flame retardant polypropylene (PP) has poor processability and seriously deteriorated material performance. We adopted a novel processing technology, solid state shear milling (S3M) by using our self-designed pan-mill equipment, to prepare even MH/PP composite powder, as the flame retardant master batch to be added to the virgin PP. This original method can achieve efficient pulverization of PP, a high degree of blending, and even dispersion of MH in the resin, thus effectively controlling the dispersion phase in solid state. Simultaneously, mechanochemical effects of S3M can induce chemical interaction between PP and MH, and improve their compatibility. Compared with conventional melt processing, S3M can greatly enhance the melt flowability, and greatly modify the melt processability of the composite materials. Also, pre-compounded through S3M, MH flame retardant PP shows remarkably enhanced flame retardancy and mechanical performance, therefore showing promise to prepare high performance composite materials with high loading level for commercial applications.

Thermal oxidative degradation kinetics of flame-retarded polypropylene with intumescent flame-retardant master batches in situ prepared in twin-screw extruder

Abstract The thermal oxidative degradation kinetics of pure PP and the flame-retarded (FR) PP materials with intumescent flame-retardant (IFR) master batches in situ prepared in twin-screw extruder were investigated using Kissinger method, Flynn–Wall–Ozawa method and Coats–Redfern method. The results showed that the activation energy order of PP and FR PP samples with different blowing agent/char former ratios obtained by Kissinger method agrees well with that obtained by Coats–Redfern one, which well illustrates the relationship between the composition of IFRs and their flame-retardancy, i.e. FR material with richer carbonization agent has higher activation energy for thermal oxidative degradation, hence leading to a better flame-retardancy. For Flynn–Wall–Ozawa method, due to its adoption of Doyle approximation, the obtained activation energy and its order of samples are very different from those of both Kissinger and Coats–Redfern methods. Criado method was finally used to determine the degradation reaction mechanism of various samples.

Solid state shear compounding to prepare flame retarded polyamide 6/melamine cyanurate

In this study, a novel technology, solid state shear compounding (S3C) carried out at ambient temperature with pan-mill type equipment, was used to prepare composite powders of polyamide 6/melamine cyanurate (PA6/MCA). The prepared powder of high melt flow index can be used as a flame retardant master batch loaded into PA6, or directly moulded into flame retarded PA6 samples. This technology resolves the limitations of conventional melt compounding in extruders by overcoming the decomposition of flame retardants at high temperatures and the phase segregation caused by thermodynamic incompatibility between flame retardant and polymer, as well as the baffle of viscous polymer melts on the dispersion of flame retardant particles in the melt compounding process, yielding an ideal mix and dispersion of MCA in PA6. Additionally, the S3C process can also provide chemical interaction between MCA and PA6 macromolecular chains, and yield in situ compatibilisation effects. During this study, it was found that the flame retarded PA6 formed by the S3C process has improved flame retarding efficiency, and the loading level of flame retardant is greatly reduced while maintaining the desired flame retardancy.

Performance of intumescent flame retardant master batch synthesized through twin-screw reactively extruding technology: effect of component ratio

A novel technology, i.e., reactive extrusion, was used to synthesize intumescent flame retardants (IFRs) and their master batches by reacting melamine phosphate (MP) and pentaerythritol (PER). Limiting oxygen index (LOI), UL94 test, melt flow index (MFI), thermogravimetric analysis (TGA), Fourier transfer infrared (FT-IR) and scanning electron microscopy (SEM) were used to investigate the effect of carbon source (char former/blowing agent ratio) of IFR on the flame retardancy and the water resistance of IFR/Polypropylene (PP) blend. The experimental results show that the char former/blowing agent ratio has a great effect on the flame retardancy and the water resistance of the composite. The flame retardant system, optimally at MP/PER=1.6 (molar ratio) or additional carbonization agent content=17.0 wt.% in intumescent system, shows excellent flame retardancy, i.e. UL94 V-0 ratings at both 3.2 and 1.6 mm thickness at 25 wt.% flame retardant (FR) loading, and UL94 V-0 rating at 3.2 mm thickness at 20 wt.% FR loading in IFR/PP formulation. Also, the water resistance of flame-retarded material was improved greatly by selecting a reasonable char former/blowing agent ratio, i.e. at MP/PER=1.6 (molar ratio) or additional carbonization agent content=17.0 wt.% in intumescent system, IFR/PP blend at 25 wt.% flame retardant loading can still reach UL94 V-0 rating after treatment with water at 70 °C for 168 h. The polarity of IFRs, dispersion of IFRs in PP matrix and compatibility of IFRs with PP matrix were also found to influence the water resistance of IFR/PP blend based on IR, water solubility test and SEM. The thermal stability of IFR/PP blend, affected by char former/blowing agent ratio, was proved to be well correlated with its flame retardancy whether before or after water treatment.

Improved production of flame-retardant masterbatches

Improved production of flame-retardant masterbatches