Better Flame Retardancy (good + flame_retardancy)

Distribution by Scientific Domains


Selected Abstracts


A study of the novel intumescent flame-retarded PP/EPDM copolymer blends

JOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2008
Shun Zhou
Abstract Flammability of polypropylene/ethylene,propylene-diene copolymer (PP/EPDM) filled with melamine phosphate (MP) and pentaerythritol phosphate (PEPA) was studied by limiting oxygen index (LOI), UL 94, and cone calorimetry. The thermal degradation of the composites was investigated using thermogravimetric analysis (TG) and real-time Fourier transform infrared spectrum (RT-FTIR), and the mechanical properties of the materials were also studied. It had been found that the PP/EPDM/PEPA/MP composites (PEPM series) showed better flame retardancy than that of the PP/EPDM composites containing MP or PEPA. TG and RT-FTIR studies indicated that the interaction occurs among MP, PEPA, and PP/EPDM. The incorporation of the flame retardants deteriorated the mechanical properties of the materials. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source]


Reactive extrusion to synthesize intumescent flame retardant with a solid acid as catalyst and the flame retardancy of the products in polypropylene

JOURNAL OF APPLIED POLYMER SCIENCE, Issue 1 2008
Yuan Liu
Abstract Reactive extrusion and solid acid catalysis technologies were adopted in the pentaerythritol,melamine phosphate (PER-MP) reaction to synthesize intumescent flame retardant, melamine salt of pentaerythritol phosphate (MPP), which was applied in flame retardant polypropylene (PP). This environment-friendly synthesis method provided a solution to the problems of conventional methods. On one hand, reactive extrusion in a twin screw extruder can effectively mix and transfer viscous materials that usually results in a tough stir in a conventional reactor, and achieve a continuous synthesis process. On the other hand, the solid acid, silicotungstic acid (STA) serving as a catalyst, can maintain a satisfactory conversion even with a low extrusion temperature and a short residence time, thus effectively suppressing foaming in the process of the reaction. Furthermore, without removal like other catalysts in general chemical reactions, STA was kept in produced MPP to constitute a synergism flame retardant system, therefore further improved the flame retardancy. LOI and UL94 test showed that the STA-catalyzed MPP (by reactive extrusion) possessed much better flame retardancy in PP when compared with the noncatalyzed MPP (by reactive extrusion), as well as present commercial MPP (by POCl3 method). In our investigation, the catalytic and synergistic effects of STA, as well as the related factors of the reactive extrusion affecting the conversion of the PER-MP reaction, flame retardancy and mechanical performance of the corresponding flame retardant PP, were systematically investigated. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source]


Effect of the organophosphate structure on the physical and flame-retardant properties of an epoxy resin

JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 3 2002
Jeng-Yueh Shieh
Abstract 2-(6-Oxido-6H-dibenzo,c,e,,1,2,oxa-phosphorin-6-yl)1,4-benzenediol (ODOPB) and bis(3-dihydroxyphenyl) phenyl phosphate (BHPP) were successfully synthesized and used as reactive flame retardants in o -cresol formaldehyde novolac epoxy resin. Because of the rigid, cyclic, side-chain structure of ODOPB, the resultant phosphorus-containing epoxy resin exhibited a higher glass-transition temperature, better flame retardancy, higher modulus, and greater thermal stability than the regular bromine-containing tetrabromobisphenol A epoxy resin and the linear, main-chain, phosphorus-containing BHPP epoxy resin. A UL-94VO rating was achieved with a phosphorus content as low as 1.1% with ODOPB (comparable to a bromine content of 12% and a phosphorus content of 2.2% with BHPP) in the cured resins, and no fumes or toxic gas emissions were observed. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 369,378, 2002 [source]


Flame retardation and thermal degradation of flame-retarded polypropylene composites containing melamine phosphate and pentaerythritol phosphate

FIRE AND MATERIALS, Issue 5 2008
Shun Zhou
Abstract The flame retardation of polypropylene (PP) composites containing melamine phosphate (MP) and pentaerythritol phosphate (PEPA) was characterized by limiting oxygen index (LOI) and UL 94. The morphology of the char obtained from the combustion of the composites was studied by scanning electron microscopy (SEM). The thermal degradation of the composites was investigated using thermogravimetric (TG) analysis and real-time Fourier transform infrared (RTFTIR) spectroscopy. It has been found that the PP composites containing only MP do not show good flame retardancy even at 40% additive level. Compared with the PP/MP binary composites, all the LOI values of the PP/MP/PEPA ternary composites at the same additive loading increase, and UL 94 ratings of the ternary composites at suitable MP/PEPA ratios are raised to V-0 from no rating (PP/MP). The TG and RTFTIR studies indicate that the interaction occurs among MP, PEPA and PP. Copyright © 2008 John Wiley & Sons, Ltd. [source]


Flame retardancy finish with an organophosphorus retardant on silk fabrics

FIRE AND MATERIALS, Issue 6 2006
Jin-Ping Guan
Abstract The paper mainly deals with flame retardancy of silk fabrics treated with a commercial organophosphorus flame retardant [N-hydroxymethyl (3-dimethyl phosphono) propionamide (HDPP), also known as Pyrovatex CP], using the pad-dry-cure-wash method. The structures and properties of the treated and control sample are discussed. The Limiting Oxygen Index (LOI) value of the modified sample is above 30%. After 50 laundry cycles, it still has some flame retardancy left. HDPP and a cross-linking agent (HMM) were bound to silk fabrics which is confirmed by FT-IR spectra and amino analysis. The reaction degree of the flame retardant with silk is also high; almost all the tyrosine units have reacted, which can be confirmed by amino acid analysis. The reaction between flame retardant and silk only occurs in the amorphous region of silk fibre, which is confirmed by X-ray diffraction analysis and amino acid analysis. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analysis show that the flame retardant causes silk fabrics to decompose below its ignition temperature (600°C) and formed carbonaceous residue or char when exposed to fire. The char behaves as a thermal barrier to fire, so silk fabrics show good flame retardancy. The treatment has a little effect on the whiteness of the silk fabrics and the tensile strength of treated silk fabrics slightly decreased; both effects are negligible. Copyright © 2006 John Wiley & Sons, Ltd. [source]