The Structure Properties Of Halogen-free Flame Retardant POE And It's Crosslinking Modification Composites

Halogen-free flame retardant ethylene-octene copolymer(POE) composite was prepared by moltenblending method, the influences of aluminum hydroxide(ATH) content, coupling processing of ATH,coated red phosphorus(CRP) association, Intumescent flame retardant(IFR) system ratio and contentto the flame retardancy and mechanical properties of materials were studied. Try to use novolacinstead of pentaerythritol(PER) to flame retardant POE. The result showed the flame retardantefficiency of ATH was very low, when the quantity of ATH was160phr, the limit the oxygenindex(LOI) of composite was only29.1, there was no rating in UL-94test, the mechanical propertieswas degraded seriously. After coupling processing with aluminum acid ester, the mechanicalproperties of composite increased firstly and then droped, but the flame retardancy of composite gotdown with the increasing of aluminum acid ester. The flame retardant efficiency of ATH wasimproced with CRP, but the LOI was degraded slightly with too much aluminum acid ester. Whenthe ratio of ammonium polyphosphate(APP)/PER/melamine(MEL) was3/1/1, the flame retardantefficiency of IFR was best. To achieve better effect of flame retardant, the quantity of IFR was stilltoo high. The quantity of IFR must be More than35phr, the UL-94test rating could reach V-0. Theeffect of novolac instead of PER was not good, the LOI of composit got down from30.2to26.1, therating of horizontal and vertical burning got down obviously.The flame retardant synergistic agent FeOOH·0.43H2O was prepared by hydrothermal method andcharaeterized by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR),thermogravimetric analysis (TG) and scanning electron microscope (SEM). ATH/FeOOH andIFR/FeOOH composites were prepared, the flame retardant performance of composites werecharaeterized by LOI, horizontal and vertical burning test, TG, FT-IR and SEM. The flame retardantsynergistic of FeOOH was studied. The result showed that FeOOH can improve the flame retardantefficiency of ATH and IFR, In addition to improve the LOI of composite, the UL-94rating and meltdrip phenomenon of composite were greatly improved, FeOOH can make the char in verticalburning test become denser and stronger, it can also increase the quality of char of high temperaturein air atmosphere.The grafting of silane and crosslinking on POE were studied. The effection of reaction time,VTMS content, DCP content to grafted degrees were studyed. The influence of DCP and VTMScontent to gel content and melting index of composite were studyed. The influence of crosslinked tovicat softening point was studyed. The melting and crystallizing process of crosslinked POE werestudied..The non-isothermal crystallization kineties of sliane crosslinked POE was studied. Thehalogen-free flame retardant crosslinked POE was studyed. The result showed that the grafteddegrees increased with the extension of reaction time, increasing of DCP ang VTMS content. DCPcan not initiate POE to crosslink, it can make the chain of POE degrade, then make the melting indexof POE increase greatly. The tiny crosslinking of POE make the melting index of POE degradegreatly. The vicat softening point increased with the increasing of crosslinking degree. The meltingand crystallizing point of crosslinked POE moved to high temperature direction in the DSC analysis.The crosslinked POE got good flame retardant performance with the ATH/FeOOH and ATH/CRPsystems. It found that the ATH/CRP system better by comprehensive evaluation, when the ratio of ATH:CRP was120:18, the comprehensive performance of composite was best.