新型无卤阻燃聚丙烯的制备与性能研究

采用碱式硫酸镁晶须(MOS)与有机蒙脱土(OMMT)作为阻燃剂制备了阻燃聚丙烯(PP),研究了MOS和OMMT用量对阻燃PP力学性能和阻燃性能的影响,并通过热失重分析(TGA)和锥形量热仪(CONE)对材料进行了表征。结果表明:MOS对PP有良好的增强阻燃作用,少量OMMT的加入可以进一步提高阻燃PP的阻燃性能。当MOS与OMMT用量分别为40.0%和3.0%时,阻燃PP的OI为28.5%,其热释放速率峰值(pHRR)和平均热释放速率(mHRR)分别为156.5kW/m2和112.9kW/m2,比基体树脂分别下降了83.3%和72.1%,同时其抑烟性能也大为改善。     

PP-g-MAH/OMMT阻燃母料的制备及其在PP中的应用

以聚丙烯接枝马来酸酐(PP-g-MAH)和有机蒙脱土(OMMT)为原料,通过熔融插层制备了PP-g-MAH/OMMT纳米复合阻燃母料,利用X射线衍射(XRD)及热失重分析(TGA)对其进行了表征,并将其与碱式硫酸镁晶须(MOS)复配,制备了阻燃性能及力学性能优良的阻燃PP。结果表明,PP-g-MAH能够插层进入OMMT层间,形成插层型纳米复合物;PP-g-MAH/OMMT中PP-g-MAH的外推起始失重温度由纯PP-g-MAH的269.8℃提高到375.6℃。以PP-g-MAH/OMMT及MOS制备的阻燃PP的热释放速率峰值(PHRR)和平均热释放速率(MHRR)分别为163.7kW/m2和117.9kW/m2,比基体树脂下降了80.3%和70.9%。     

PP/纳米蒙脱土复合材料炭层结构对阻燃性能的影响

采用熔融插层法制备了不同纳米蒙脱土含量的聚丙烯(PP)/有机蒙脱土(OMMT)和PP/无机蒙脱土(MMT)复合材料,且评价了复合材料的阻燃性能:采用数码相机、扫描电子显微镜观察了燃烧残余物结构.加入OMMT可显著提高PP/OM MT的阻燃性能:纯PP的热释放速率(HRR)峰值为1 337.59 kW/m2;w(OMMT...     

氨基硅油对氢氧化镁及有机蒙脱土阻燃LLDPE的影响

用氢氧化镁(MH)和有机蒙脱土(OMMT)作为阻燃剂制备了阻燃线型低密度聚乙烯(LLDPE),研究了氨基硅油(ASO)对阻燃LLDPE力学性能及阻燃性能的影响。通过锥形量热仪(CONE)和热失重分析(TGA)对材料进行了表征。结果表明:ASO提高了阻燃性能和抑烟效果。当ASO用量为2%时,阻燃LLDPE的热释放速率峰值(pHRR)和平均热释放速率(mHRR)分别降低到169.6kW/m2和86.7kW/m2,比加入ASO前下降了20.5%和9.7%;烟产生速率峰值(pSPR)和总生烟量(TSP)分别降低到0.017m2/s和0.4m2。此外,ASO提高了材料的断裂伸长率和冲击强度。     

PP/PA6/OMMT复合材料力学性能与结晶性能的研究

采用3种不同有机改性过的蒙脱土(牌号为DK2,DK3,DK5)熔融插层法制备了PP/PA6/OMMT纳米复合物材料,在此基础上使用1%～7%的DK2的蒙脱土再次制备PP/PA6/OMMT纳米复合物材料,借助力学性能测试和差示扫描量热法(DSC)对体系的力学性能和结晶性能进行了研究。结果表明:使用DK2制备的复合材料的力学性能优于使用DK3和DK5制备的复合材料的力学性能;相对于纯PP,PP/PA6/OMMT纳米复合物材料随OMMT含量的增加,拉伸强度和弯曲强度是先增加后降低,最大下降幅度分别为8.7%和5.3%;冲击韧性一直上升达到9.61kJ/m2。OMMT的加入,对PP/PA6有异相成核的作用,提高PP/PA6的结晶速率和结晶度。     

OMMT和EG/MH协同阻燃LLDPE的研究

采用氢氧化镁(MH)、膨胀石墨(EG)和有机蒙脱土(OMMT)为阻燃剂制备了无卤阻燃线性低密度聚乙烯(LLDPE),研究了OMMT对LLDPE/EG/MH阻燃性能和力学性能的影响。结果表明:少量OMMT的加入,可以有效改善LLDPE/EG/MH的力学性能、阻燃性能和热稳定性。当OMMT质量分数为3.0%时,LLDPE/EG/MH/OMMT的拉伸强度和冲击强度分别为1.4 MPa和26.5 kJ/m~2;极限氧指数为35.0%,符合UL-94 V-0级;其热释放速率峰值、平均热释放速度、生烟速率和总生烟量比LLDPE/EG/MH的低。     

氢氧化物对NER/OMMT与磷酸酯体系阻燃聚丙烯的影响

将氢氧化物加入到酚醛环氧树脂/有机蒙脱土(NER/OMMT)与磷酸酯阻燃聚丙烯(PP)体系,考察了氢氧化物和磷酸酯的种类和用量等对PP燃烧性能和力学性能的影响。在NER/OMMT与磷酸三苯酯(TPP)总用量仅为10wt%的情况下制得了氧指数高达30.0%的阻燃聚丙烯,并且热释放速率峰值比纯PP下降了49%,在降低了材料的毒害性的同时提高了其性能,为通用塑料工程化探索了一条行之有效的途径。     

OMMT对POE/POE-g-MAH/DB-AO/OMMT复合材料性能的影响

采用熔融插层法制备了乙烯-1-辛烯共聚物(POE)/马来酸酐(MAH)接枝POE(POE-g-MAH)/十溴二苯醚(DB)-三氧化二锑(AO)/有机蒙脱土(OMMT)复合材料。采用X射线衍射仪、透射电子显微镜分析了OMMT在POE/POE-g-MAH/DB-AO/OMMT复合材料中的分散形态,研究了OMMT与DB-AO的协效作用对复合材料阻燃性能和力学性能的影响。结果表明:OMMT片层均匀地分散在母粒中,达到了纳米级的分散,且大部分以剥离形态存在;当w(OMMT)在3%以内,复合材料的阻燃级别均为FV-0级;随着w(OMMT)增加,复合材料的热释放速率由964.58 kW/m2降到494.72 kW/m2,质量损失速率由0.285 g/s降到0.137 g/s,表明OMMT与DB-AO的协效作用能有效提高复合材料的阻燃性能;加入OMMT有利于提高复合材料的定伸应力和撕裂强度。     

单分子阻燃剂MPP的合成及其对醇酸树脂的阻燃抑烟

用多聚磷酸、季戊四醇和三聚氰胺合成单分子磷-氮系膨胀型阻燃剂——季戊四醇多聚磷酸酯蜜胺盐(MPP),采用傅里叶变换红外光谱仪表征了其分子结构,采用锥形量热仪和烟密度测定仪评价了MPP对醇酸树脂的阻燃和抑烟特性。结果表明:MPP对醇酸树脂的阻燃性能优于聚磷酸铵、季戊四醇、三聚氰胺构成的传统三组分膨胀型阻燃剂(IFR),有机蒙脱土(OMMT)以及IFR/OMMT复合阻燃剂。w(MPP)为30%时,醇酸树脂的热释放速率峰值从839.65 k W/m2降至251.89 k W/m2,总热释放速率从50.98 MJ/m2降至25.19 MJ/m2,动态生烟速率和有焰燃烧条件下的静态生烟速率降低,无焰燃烧条件下的静态生烟速率增大。     

PP/MWNTs和PP/OMMT复合材料的热降解动力学研究

采用熔融共混法制备了聚丙烯/多壁碳纳米管(PP/MWNTs)与聚丙烯/纳米有机蒙脱土(PP/OMMT)复合材料,利用热重分析法研究了PP、PP/MWNTs及PP/OMMT在氮气气氛中的热降解过程,并采用Kissinger及Ozawa方法研究了复合材料的热降解动力学及热降解表观活化能.结果表明,MWNTs和OMMT的加入...     

Synergistic Effect of Epoxy/Organophilic Montorillonite Nanocomposites and Triphenyl Phosphate on Flame Retardance Enhancement of Polypropylene

Epoxy/organophilic montorillonite (Epoxy/OMMT) nanocomposites were prepared by epoxy intercalated into the interlayer of OMMT, and flame retardant polypropylene (PP) was obtained with Epoxy/OMMT nanocomposites and triphenyl phosphate (TPP) mixture as flame retardant agent. The effect of epoxy sorts, mass ratio of OMMT and Epoxy, and the contents of Epoxy/OMMT and TPP on properties of PP were studied. It was found that there is a remarkable synergistic flame retardant effect of novolac epoxy/organophilic montorillonite (NE/OMMT) and TPP on PP. Flame retardant PP with oxygen index (OI) value of 36.5%, peak heat release rate (PHRR) of 654 kW/m², notched Izod impact strength of 6.93 kJ/m² and tensile strength of 30.56 MPa was obtained when the mass ratio of OMMT and NE is 5:100, the content of NE/OMMT and TPP is 13.33 and 6.67 wt.%, respectively. The materials were characterized via X-Ray diffraction (XRD), transmission electron microscope (TEM), Fourier transform infrared spectrum (FT-IR), and thermogravimetry (TG). The XRD results and TEM photograph indicate OMMT is exfoliated in PP matrix when the mass ratio of OMMT and NE is lower than 10:100. The TG results show the evaporation of TPP is greatly hampered by NE/OMMT nanocomposite. PP with NE/OMMT-TPP has an onset weight loss temperature 31.7°C higher than PP with NE-TPP because of the shielding effect of OMMT layers. The FT-IR spectra indicate phosphoric acid is generated from TPP and carboxylic acid and phenyl ether are generated from NE under thermal degradation, which further results in the formation of thermally stable char. This charring process is also affirmed by the wide thermally stable zone at 380–550°C in TG curves of PP with NE/OMMT-TPP or NE-TPP.     

线性低密度聚乙烯/有机蒙脱土纳米复合材料的制备及性能研究

通过熔融共混法制备了线性低密度聚乙烯／有机蒙脱土（LLDPEtOMMT）纳米复合材料,采用X-射线衍射分析（XRD）和透射电镜（TEM）对材料的结构进行表征,研究了OMMT的用量对LLDPE／OMMT纳米复合材料力学性能及阻燃性能的影响。结果表明,当OMMT的用量为30％（重量百分比）8寸,材料的极限氧指数（LOI）从180％提高到23．8％,热释放速率峰值（PHRR）从LLDPE的771．9kW／m2下降到5113kW／m2,下降幅度高达33．8％,表现出较好的阻燃性能;同时材料也呈现出良好的力学性能。     

Effect of modified layered double hydroxide on the flammability of intumescent flame retardant PP nanocomposites

The dodecyl sulfate intercalated CaMgAl-hydrotalcites (layered double hydroxides [LDHs]) were successfully prepared by co-precipitation method, and characterized by X-ray diffraction analysis, infrared spectroscopy (Fourier transform infrared spectra [FT-IR]), thermogravimetry (TG-DTA), scanning electron microscope, and Brunner−Emmet−Teller (BET). The prepared LDHs were added to the intumescent flame retardant (IFR) polypropylene (PP) nanocomposites, and the limiting oxygen index method (LOI), vertical combustion method (UL-94), cone calorimetry (CCT), and other test methods were used to study its thermal stability and combustion performance. The results showed that when the flame retardant was composed of 23 wt% IFR and 2 wt% O-SDS-LDHs, the LOI value of the material was increased to 31.5%, reaching the V-0 level, and the flame retardant performance was significantly improved. The results also showed that there was a significant synergistic effect between IFR and O-SDS-LDHs, which could improve the thermal stability and graphitization degree of PP nanocomposites. In addition, the peak heat release rate, total heat release, and total smoke production of the PP/IFR/O-SDS-LDHs system were 177 kW/m², 101 MJ/m², and 15.4 m², respectively, which were 82.2%, 51.0%, and 23.0% lower than those of pure PP, respectively. These improvements could be attributed to the presence of dense and continuous char layer formed by the synergistic effect.     

OMMT对POE/Mg（OH）2复合材料性能的影响

通过熔融共混法制备了POE/POE-g-MAH/Mg(OH)2及POE/POE-g-MAH/Mg(OH)2/OMMT复合材料,采用X射线衍射(XRD)仪和透射电镜(TEM)对OMMT在POE/POE-g-MAH/OMMT(OMMT质量分数为11%)母粒中的分散情况进行了表征,利用水平-垂直燃烧仪和锥形量热仪对两种复合材料的阻燃性能进行了测试。XRD和TEM表明,在母粒中OMMT大部分以剥离形态存在,达到了纳米分散;垂直燃烧和锥形量热仪实验表明,随着OMMT含量的增加,复合材料的热释放速率(HRR)降低(由202.9 kW/m2降低到135.4 kW/m2),表明Mg(OH)2和OMMT具有阻燃协效作用。力学性能测试表明OMMT的加入有利于复合材料力学性能的提高。     

PP/有机改性蒙脱土纳米复合材料的性能

采用熔融插层法制备了聚丙烯/有机改性蒙脱土(PP/OMMT)纳米复合材料,研究了OMMT用量对PP基体力学性能和阻燃性能的影响,利用透射电镜(TEM)分析了OMMT在PP基体中的分散性。结果表明:OMMT的加入有助于提高PP基体的力学性能和阻燃性能;熔融插层法可以使PP的大分子链有效地插入OMMT的片层之间;随着OMMT用量的增加,其在PP基体中的分散性变差。     

In situ synthesis and characterization of polypropylene/polyvinyl acetate‐organophilic montmorillonite nanocomposite

A novel polymer‐nanoclay hybrid nanocomposite based on polyvinyl acetate (PVAc)‐organophilic montmorillonite (OMMT) has been reported via an in situ intercalated polymerization technique. The hybrid material was synthesized by one‐step emulsion polymerization of vinyl acetate in the presence of OMMT using polyvinyl alcohol as the stabilizing agent. The intercalated polymerization was characterized by X‐ray diffraction (XRD). The XRD patterns show that the interlayer spacing of OMMT after polymerization increased from 2.64 to 3.78 nm, indicating that the large macromolecular chain of PVAc was formed in the OMMT interlayer space. The Fourier transform infrared spectrum showed the characteristic absorption of PVAc in the OMMT particles separated from the nanocomposite, and the position of peaks shifted to high wave numbers. This showed that there was an interaction between PVAc and OMMT nanoparticles. A two‐fold blend composed of PVAc‐nano‐OMMT/PP was prepared by the melt‐blending technique. XRD and transmission electron microscopy images of the PVAc‐nano‐OMMT/PP composite further confirmed the formation of a partially delaminated nanocomposite structure. Thermogravimetry results showed that the thermal stability of PVAc‐nano‐OMMT/PP was greater than that of either polypropylene (PP) or Nano‐OMMT/PP blend. PVAc‐nano‐OMMT/PP had better toughness, as the mass fraction of OMMT was 5 wt %. The flame retardancy of PP, Nano‐OMMT/PP, and PVAc‐nano‐OMMT/PP composites was also studied. According to the limiting oxygen index (LOI) data and Cone calorimeter test, the addition of PVAc‐OMMT resulted in higher LOI and lower heat release rate, effective heat of combustion, smoke release course, and better flame retardancy and barrier properties. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

“一锅法”合成双组分镁基阻燃剂及性能研究

基于轻烧氧化镁为原料,通过“一锅法”合成了一种具有氢氧化镁（MH）和碱式碳酸镁（MC）双组分多级结构的一体化高效无卤复合阻燃剂（MCMH）。将MCMH和MH分别与聚丙烯（PP）密炼共混,经模压成型制备了PP/MCMH和PP/MH复合材料,并对比研究了MCMH与MH应用于PP的阻燃性能。结果表明,合成的MCMH是氧化镁先水化转变为氢氧化镁,然后部分氢氧化镁与碳酸氢铵反应生成碱式碳酸镁,呈现花状多级结构。当阻燃剂质量分数占复合材料的50%时,PP/MCMH复合材料的热释放速率（HRR）峰值和烟雾产生率（SPR）峰值较PP/MH复合材料大幅降低,分别为299 kW/m²和0.038 m²/s。该方法原料来源广泛,工艺简单易行,具有规模化生产和应用的潜力。