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Retardant Properties (retardant + property)

Distribution by Scientific Domains
Polymers and Materials Science75%

Kinds of Retardant Properties

  • flame retardant property
    		•

    Selected Abstracts

    Synergistic Effect of the Charring Agent on the Thermal and Flame Retardant Properties of Polyethylene

    MACROMOLECULAR MATERIALS & ENGINEERING, Issue 2 2004
    Xiao-Ping Hu
    Abstract Summary: A new charring agent (CA), a derivative of triazines, was synthesized. The flame retardancy and thermal behavior of a new intumescent flame-retardant (IFR) system for PE (PE-IFR) were investigated by limited oxygen index (LOI), UL-94 test, thermogravimetric analysis (TGA), and FTIR spectroscopy. The TG curves shows that the amount of residue of IFR-PE system are largely increased compared to those of PE at temperatures ranging from 350 to 700,°C. The new PE-IFR system can apparently reduce the amount of decomposing products at higher temperatures and promotes the formation of carbonaceous charred layers. It showed a distinct synergistic flame retardant effect (SE) between nitrogen and phosphorus. The flame retardant PE composition was optimized to achieve a LOI value of 31.2 and UL-94 V-0 performance with the synthesized charring agent, ammonium polyphosphate (APP). TG curves of PE, APP, CA, and different PE/CA/APP systems. [source]

    Combination of a hydroxy-functional organophosphorus oligomer and a multifunctional carboxylic acid as a flame retardant finishing system for cotton: Part II.

    FIRE AND MATERIALS, Issue 5 2003
    Formation of calcium salt during laundering
    Abstract Multifunctional carboxylic acids, such as 1,2,3,4-butanetetracarboxylic acid (BTCA), were used to bond a hydroxy-functional organophosphorus oligomer (FR) to cotton fabric in the presence of a catalyst, such as sodium hypophosphite (NaH2PO2). Previously, it was found that the cotton fabric treated with FR and BTCA showed a high level of phosphorus retention after one home laundering cycle. However, the flame retardant properties quickly deteriorated as the number of home laundering cycles was increased. In this research, it was found that the free carboxylic acid groups bound to the cotton fabric form an insoluble calcium salt during home laundering, thus diminishing the flame retardant properties of the treated cotton fabric. It was also found that the free carboxylic acid groups on the treated cotton fabric were esterified by triethanolamine (TEA), and that the formation of calcium salt on the fabric was suppressed by the esterification of the free carboxylic acid groups by TEA. The cotton fabric treated with BTCA and the hydroxy-functional organophosphorus oligomer significantly improved its flame retardance when a new catalyst system consisting of hypophosphorous acid (H3PO2) and TEA was used in the system. Copyright © 2003 John Wiley & Sons, Ltd. [source]

    Flame retardant properties of EVA-nanocomposites and improvements by combination of nanofillers with aluminium trihydrate

    FIRE AND MATERIALS, Issue 5 2001
    Günter Beyer
    Flame retardant nanocomposites are synthesized by melt-blending ethylene,vinyl acetate copolymers (EVA) with modified layered silicates (montmorillonites). Thermogravimetric analysis performed under different atmospheres (nitrogen and air) demonstrated a clear increase in the thermal stability of the layered silicate-based nanocomposites. The use of the cone calorimeter to investigate the fire properties of the materials indicated that the nanocomposites caused a large decrease in heat release. The char-formation is the main factor important for improvement and its function is outlined. Further improvements of the flame retardancy by combinations of nanofillers and traditional FR-additives on the basis of metal hydroxides were also studied. Copyright © 2002 John Wiley & Sons, Ltd. [source]

    EVA Nanocomposites Elaborated with Bentonite Organo-Modified by Wet and Semi-Wet Methods

    MACROMOLECULAR MATERIALS & ENGINEERING, Issue 9 2007
    Miguel Angel Cárdenas
    Abstract EVA copolymer/organoclay nanocomposites were prepared using melt-compounding. Organoclays were obtained using wet and semi-wet modification methods. These methods enable us to obtain organoclays with adequate modifier incorporation, but organoclays with a homogeneous and narrow agglomeration size distribution were obtained only with the wet method. TS and EB were higher for nanocomposites obtained with organoclays prepared using the wet method. Analysis of Limiting Oxygen Index, UL94 test and Cone Calorimeter test showed that the retardant properties of nanocomposites were also influenced by the kind of modifiers and the modification method. [source]

    Use of Turkish huntite/hydromagnesite mineral in plastic materials as a flame retardant

    POLYMER COMPOSITES, Issue 10 2010
    Hüsnügül Y, lmaz Atay
    In this study, the flame retardancy properties of huntite/hydromagnesite mineral in plastic compounds were investigated for potential electrical applications. Before the production of composite materials, huntite/hydromagnesite minerals were ground to particle sizes of 10, 1, and 0.1 ,m. Phase and microstructural analysis of huntite/hydromagnesite mineral powders were undertaken using XRD and SEM-EDS preceding the fabrication of the composite materials. The ground minerals with different particle size and content levels were subsequently added to ethylene vinyl acetate copolymer to produce composite materials. After fabrication of huntite/hydromagnesite reinforced plastic composite samples, they were characterized using DTA-TG, FTIR, and SEM-EDS. Flame retardancy tests were undertaken as a main objective of this research. The size distribution and the mineral content effects are measured regarding the flame retardancy of the polymer composites It was concluded that the flame retardant properties of plastic composites were improved as the mineral content increased and the size was reduced. POLYM. COMPOS., 31:1692,1700, 2010. © 2010 Society of Plastics Engineers. [source]

    Flame retardancy and toughening of high impact polystyrene

    POLYMER COMPOSITES, Issue 4 2007
    Wenguang Cui
    Flame retardant high impact polystyrene (HIPS) was prepared by melt blending HIPS, nano-modified aluminum trihydrate (nano-CG-ATH), red phosphorus masterbatch (RPM), and modified polyphenylene oxide (MPPO). Styrene-butadiene-styrene (SBS) was used as a toughener in this research. The effects of nano-CG-ATH, RPM, MPPO, and SBS on properties of HIPS composites were studied by combustion test, mechanical tests, and thermogravimetric analysis. The morphologies of fracture surfaces and char layers were characterized through scanning electron microscopy (SEM). The HIPS/nano-CG-ATH/RPM/MPPO (60/6/9/25) composite and its combustion residues at various temperatures were characterized by Fourier transform infrared (FTIR) spectra analysis. The results showed that the UL-94 rating of the HIPS/nano-CG-ATH/RPM/MPPO (60/6/9/25) composite reached V-0 and its char layer after flame test was integrated, but its impact strength was low. Addition of SBS improved its impact property and did not influence its thermal and flame retardant properties but lowered its tensile strength and flexural modulus to some extent. The FTIR spectra confirmed that the POC group was present in the charred substance. POLYM. COMPOS., 28:551,559, 2007. © 2007 Society of Plastics Engineers [source]

    Effects of synthesis conditions on crystal morphological structures and thermal degradation behavior of hydrotalcites and flame retardant and mechanical properties of EVA/hydrotalcite blends

    POLYMER COMPOSITES, Issue 2 2007
    Longchao Du
    The effects of synthesis methods and reaction conditions on the crystal morphological structures and thermal degradation behavior of hydrotalcites have been studied by X-ray diffraction (XRD), transmission electron microscopy (TEM), particle size analysis (PSA), and differential thermal analysis (DTA). The flame retardant and mechanical properties of ethylene,vinyl acetate (EVA) blends with the corresponding hydrotalcites have been estimated by limiting oxygen index (LOI), UL-94, and mechanical measurements. The results from the XRD, TEM, and PSA demonstrate that the hydrotalcites synthesized by ultrasound method have larger crystal sizes and particle size distribution than those by mechanical stirring method. Higher reaction temperature, longer dripping time, and lower solution concentration can increase the crystal and particle sizes of ultrasound-synthesized hydrotalcites, whereas the longer ultrasound aging time can increase the crystal sizes and decrease the particle sizes of hydrotalcites because of the smashing conglomeration. The DTA data give a positive evidence that the hydrotalcite samples prepared by mechanical stirring method with longer alkaline dripping time have higher thermal degradation temperature than those by ultrasound method, since the ultrasound-synthesized hydrotalcites have more lattice defects than stirring-prepared hydrotalcites. The data from LOI, UL-94, and mechanical tests show that the ultrasonic-synthesized hydrotalcites have better flame retardant properties, whereas the stirring-synthesized hydrotalcites have better tensile strength in the EVA/hydrotalcite blends. POLYM. COMPOS., 28:131,138, 2007. © 2007 Society of Plastics Engineers [source]

    Flame retardancy of nanocomposites based on organoclays and carbon nanotubes with aluminium trihydrate,

    POLYMERS FOR ADVANCED TECHNOLOGIES, Issue 4 2006
    Günter Beyer
    Abstract The addition of aluminium trihydrate as a microfiller to organoclays or carbon nanotubes is essential to generate nanocomposites with sufficient flame retardant properties as requested by the industry. Cables using the combination of organoclays or carbon nanotubes and aluminium trihydrate demonstrate the applications of these nanocomposites as a new concept for flame retardancy. Copyright © 2006 John Wiley & Sons, Ltd. [source]