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。     

动态熔融插层HIPS/蒙脱土复合材料阻燃性能的研究

采用动态熔融法分别制备高冲击强度聚苯乙烯/有机蒙脱土(HIPS/OMMT)复合材料和高冲击强度聚苯乙烯/钠基蒙脱土(HIPS/Na+-MMT)复合材料,利用锥形量热仪测试复合材料的阻燃性能,结果表明:HIPS/OMMT复合材料的热释放速率(HRR)、生烟速率(SPR)、质量损失速率(MLR)等燃烧性能参数均明显降低,表现出较好的阻燃性和抑烟性;Na+-MMT阻燃HIPS与OMMT阻燃HIPS复合材料比较,HIPS/OMMT复合材料的阻燃性明显优于HIPS/Na+-MMT。通过研究复合材料的阻燃性能,结合燃烧残余物的微观结构和宏观形貌分析,探讨了复合材料的阻燃机理。     

用锥形量热仪研究PS/MH复合材料燃烧性能

将聚苯乙烯(PS)树脂与改性后的氢氧化镁(MH)直接进行熔融复合制备PS/MH复合材料,采用锥形量热仪对复合材料的燃烧行为进行了研究.结果表明,加入20份MH可使PS的峰值热释放速率(HRRpeak)、峰值质量损失速率(MLRpenk)和峰值生烟速率(SPRpeak)分别降低57.9%,40.9%和52.1%,引入MH后复合材料的热释放速率(HRR)、质量损失速率(MLR)和生烟速率(SPR)等燃烧性能参数均显著降低.材料的燃烧时间延长,分解速率减小.随着MH含量增加.复合材料的燃烧性能参数均明显降低.表现出良好的阻燃性和抑烟性.     

磷硅复合物的制备及其改性Mg(OH)_2阻燃LLDPE的研究

用9,10-二氢-9-氧-10-磷杂菲-10-氧化(物DOPO)与γ-(2,3-环氧丙基)丙基三甲氧基硅烷(GPTMS)制备了新型磷硅复合物(P-Si),并以P-Si改性的氢氧化镁(MH)制备阻燃线型低密度聚乙烯(LLDPE),研究了P-Si用量对LLDPE阻燃性能和力学性能的影响。通过锥形量热仪(CONE)和扫描电子显微镜(SEM)等对材料进行了表征。结果表明:P-Si在改善MH与基体树脂相容性的同时,与MH有很好的协同阻燃作用。当P-Si用量为MH的5%时,阻燃LLDPE的氧指(数OI)从30.0%提高到36.5%,热释放速率峰值(pHRR)和平均热释放速率(mHRR)也大幅度下降。     

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。     

EG与BHAPE对RPUF燃烧及成炭作用的影响

制备了可膨胀石墨(EG)和N,N-[双(2-羟乙基)氨甲基]磷酸二乙酯(BHAPE)单独添加及复配使用阻燃的硬质聚氨酯泡沫塑料(RPUF),通过万能拉伸试验机、组合冲击试验机、氧指数仪、综合热分析仪、锥形量热仪和扫描电镜(SEM)等测试,对力学性能、阻燃性、热稳定性、燃烧性能及炭层形貌等进行了分析。结果表明,BHAPE的添加能够改善RPUF的比冲击强度,减少EG对体系力学性能的损害;氧指数(LOI)的实际值明显高于计算值,复配组分的LOI由20.3%提高到29.2%,EG/BHAPE具有显著的协同效应;EG/BHAPE复配使阻燃体系的初始分解温度、最大热解速率、热释放速率、总热及总烟释放量降低,残炭率提高,燃烧后形成厚且致密的炭层。     

阻燃功能核壳结构木塑复合材料制备及性能研究

通过在表层添加有机改性蒙脱土(OMMT)与聚磷酸铵(APP)以及纳米氢氧化镁[Mg(OH)_2]与APP制备具有阻燃功能的核壳型木塑复合材料,并利用力学性能测试、锥形量热测试和热重分析,研究了阻燃剂对核壳型木塑复合材料的力学性能、燃烧性能和热稳定性能的影响。结果表明,OMMT与APP有更好的协同效果和阻燃效果,其热释放总量以及热释放速率都呈下降趋势,但是复配之后的产烟量却增多。热失重分析结果表明,APP与OMMT的复配和APP与Mg(OH)_2的复配相比较,前者残炭率更高,达到了55.2%。两种阻燃剂复配后弯曲强度和弹性模量呈现下降趋势,力学强度下降。综合比较,APP与OMMT复配阻燃性能更好。     

氢氧化镁/红磷填充LLDPE的阻燃性及力学性能研究

以氢氧化镁(MH)为主阻燃剂、红磷为辅助阻燃剂,制备了一种无卤、低烟线型低密度聚乙烯(LLDPE)阻燃材料,利用氧指数(OI)和力学性能测试探讨了阻燃剂复配对该阻燃LLDPE力学性能及阻燃性能的影响,并通过热重(TG)和差示扫描量热分析(DSC)考察了材料的结构和性能。结果表明:随着红磷用量的增大,阻燃LLDPE的阻燃性能和拉伸强度明显提高,但缺口冲击强度和断裂伸长率有所下降;同时材料的结晶度下降、热稳定性提高。     

PS/OMMT纳米复合材料制备及其燃烧行为

将有机化蒙脱土(OMMT)和引发剂分散在苯乙烯(St)单体中混合均匀后一步法浇铸成型,得到聚苯乙烯(PS)/OMMT复合材料。研究了复合材料的结构和燃烧行为。结果表明,用原位本体聚合法得到的PS/OMMT复合材料为插层型纳米复合材料,引入OMMT可以显著降低PS的热释放速率、质量损失速率和生烟速率,增加PS的氧指数和燃烧残余物数量。随着OMMT用量增加,复合材料的阻燃性和抑烟性显著改善。     

蒙脱土/EPDM纳米复合材料燃烧性能的研究

采用熔融插层法制备了蒙脱土/EPDM纳米复合材料,并研究了燃烧性能。结果表明,EPDM大分子不能与未有机化的钠基蒙脱土(Na+-MMT)插层复合,但能有效插入有机蒙脱土(OMMT)片层之间,形成OMMT/EPDM插层纳米复合材料。Na+-MMT对改善蒙脱土/EPDM纳米复合材料的阻燃和抑烟效果不明显;OMMT/EPDM纳米复合材料的热释放速率、总生烟量及烟密度等参数均明显降低;随OMMT用量的增大,阻燃性和抑烟性变得越来越好,最后趋于稳定。     

The combination of expandable graphite,organic montmorillonite,and magnesium hydrate as fire‐retardant additives for ethylene–propylene–diene monomer/chloroprene rubber foams

The fire retardancy and flame‐retardant mechanism of expandable graphite (EG), organic montmorillonite (OMMT), and magnesium hydrate (MH) in ethylene‐propylene‐diene monomer/chloroprene rubber (EPDM/CR) foams were investigated. The results indicated that the combination of EG and OMMT remarkably improved the fire‐retardant property compared to the control samples, and better fireproof performance was achieved when MH was used as the third coretardant unit. The structure of the obtained EPDM/CR/OMMT composites was characterized by X‐ray diffraction, and the results showed that the composites had an intercalated nanostructure. The limiting oxygen index, vertical burning test, and cone calorimeter test results showed that the LOI values and UL‐94 rating increased while the second peak of the heat release rates (HRR) decreased within the EG/OMMT system. In particular, the second pHRR disappeared when the EG/OMMT/MH system was used as a flame retardant. Moreover, the results of thermogravimetric analysis showed that the combination of EG and OMMT reduced the thermal‐degradation rates and mass‐loss percentages. Furthermore, observation by scanning electron microscopy revealed that EG and OMMT left over after combustion formed a complete, compact, and rigid charred layer with a mosaic structure of expanded graphite embedded in cortical‐honeycomb layers of OMMT. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44929.     

A novel phytic acid based flame retardant to improve flame retardancy,hydrophobicity and mechanical properties of linear low-density polyethylene

Exploiting high phosphorus content of phytic acid, it was grafted onto magnesium hydroxide (MH) by neutralization reaction to obtain MGPA, a flame retardant. A current study investigated the effect of MGPA on hydrophobicity, flame retardancy, and mechanical properties of MGPA-linear low-density polyethylene (LLDPE) composites. The LLDPE composite with 50 parts of MGPA has the better flame retardancy and thermal stability with a limiting oxygen index of 23.3%, which is higher than that of neat LLDPE (17%). In addition, MGPA could effectively promoted LLDPE to form a continuous and compact char residue during combustion, which reduce the peak of heat release rate and total smoke production value of LLDPE composite by 70% and 36%, respectively, and the char residue rate increase to 67.5%. Furthermore, the maximum of loss-rate showed by LLDPE composite with MGPA reduce to 1.25%/min while the value of LLDPE composite with MH is 1.8%/min. Meanwhile, the LLDPE composite with MGPA show remarkable elongation at break and hydrophobicity, which are 398% and 99°, respectively. In addition, this study presents a substantial flame retardancy and interfacial compatibility of MGPA for extending the applications of flame-retardant LLDPE composites.     

Effects of zinc borate and microcapsulated red phosphorus on mechanical properties and flame retardancy of polypropylene/magnesium hydroxide composites

In this paper, the mechanical properties and flame retardancy of zinc borate (ZB) and microcapsulated red phosphorus (MRP) with modified magnesium hydroxide (MH) in flame-retardant polypropylene (PP) were studied by mechanical properties test, UL-94 test, and thermogravimetric analysis (TGA). The crystallization behaviors of the composites were investigated by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). The addition of ZB could improve tensile strength and elongation at break of PP/MH composite. The MRP powders had a little effect on the mechanical properties of the PP composites. DSC results showed the addition of ZB and MRP weakened the heterogeneous nucleation effect of MH on PP. The addition of ZB and MRP had a great effect on the flammability of the PP/MH/EG composites. The thermal stability of PP/MH/ZB and PP/MH/ZB/MRP composites was better than that of PP/MH composite.     

Combustion characteristics of halogen‐free flame‐retarded polyethylene containing magnesium hydroxide and some synergists

Halogen‐free flame‐retarded polyethylene materials have been prepared by using magnesium hydroxide (MH) as a flame retardant combined with red phosphorous (RP) and expandable graphite (EG) as synergists. The effects of these additives on the combustion behavior of the filled linear low density polyethylene (LLDPE), such as a limiting oxygen index (LOI), the rate of heat release (RHR), the specific extinction area (SEA), etc., have been studied by the LOI determination and the cone calorimeter test. The results show that RP and EG are good synergists for improving the flame retardancy of LLDPE/MH formulations. In addition, a suitable amount of ethylene and vinyl acetate copolymer (EVA) added in the formulations can increase the LOI values while promoting the char formation and showing almost no effect on the RHR and SEA values. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 206–214, 2001     

苯氧基环三磷腈对聚乙烯性能的影响

研究了苯氧基环=三磷腈(PCPZ)对线型低密度聚乙烯(LLDPE)阻燃性能、力学性能、流变性能的影响规律.结果表明,PCTP与LLDPE树脂基体界面作用较弱,以颗粒形式分布于基体树脂之中;PCTP的加入可提高LL-DPE的阻燃性能和熔融流变性能,但同时导致拉伸强度、缺口冲击强度下降.     

Enhancement of organoclay on thermal and flame retardant properties of polystyrene/magnesium hydroxide composite

Organoclay (organically modified montmorillonite, OMMT) was introduced to the composite of polystyrene/magnesium hydroxide (PS/MH) by melt compounding. The structure of the obtained PS/MH/OMMT composite was characterized by X‐ray diffraction and transmission electron microscopy. Thermal degradation behavior and flame retardancy of the composite were investigated by various means. It is shown that the PS/MH/OMMT composite has an intercalated nanostructure with the PS chains intercalated between the OMMT layers and the MH particles dispersed evenly in the PS matrix. Compared with the PS/MH composite containing identical amount of flame retardant, the introduction of OMMT has increased the thermal degradation temperature and lowered the mass loss rate at high temperatures. The PS/MH/OMMT nanocomposite can produce a more continuous and compact charred residue layer upon degradation both in air and burnt in flame than the PS/MH composite. Because of formation of this highly thermally stable and insulating charred residue layer, the nanocomposite exhibits much improved thermal endurance, flame retardancy, smoke suppression, and dripping resistance. Moreover, the combination of MH and OMMT makes the composite more difficult to ignite and decreases the release of toxic gas. The advantage of the PS/MH/OMMT nanocomposite is more pronounced in the early stage of combustion. POLYM. COMPOS., 37:746–755, 2016. © 2014 Society of Plastics Engineers     

PP/SEBS/MH复合材料的制备及其性能研究

采用极限氧指数（LOI）和热重分析（TGA）研究了聚丙烯（PP）/氢化苯乙烯-丁二烯-苯乙烯嵌段共聚物（SEBS）/氢氧化镁（MH）复合材料的阻燃性能和热降解行为;探讨了SEBS和MH分别对PP/SEBS共混体系和PP/SEBS/MH复合材料力学性能和熔体流动速率的影响。结果表明：PP/SEBS/MH复合材料的力学性能和加工流动性能随着MH的质量分数增加而降低;复合材料高温下的热稳定性得到提高,MH分解吸热降低材料的热降解速率;MH以吸热方式在凝缩相和气相中发挥阻燃作用,复合材料阻燃性能得到提高,当MH的质量分数为60%时,LOI可达26.3%。     

OMMT对LGFPP/IFR阻燃性能、燃烧性能及力学性能的影响

采用熔融共混技术制备了长玻璃纤维增强聚丙烯/膨胀阻燃剂/有机蒙脱土(LGFPP/IFR/OMMT)复合材料。利用极限氧指数(LOI)、锥形量热仪(CONE)以及万能力学试验机,表征了LGFPP/IFR/OMMT复合材料的阻燃性能、燃烧性能以及力学性能。氧指数测试结果表明,OMMT使LGFPP/IFR体系的氧指数提高。当添加2%OMMT时,LGFPP/IFR/OMMT复合材料的氧指数提高至24.2%。锥形量热仪测试结果表明,LGFPP/IFR体系的热释放速率峰值(PHRR)、烟雾生产率(THR)及引燃时间(TTI)均由于添加OMMT而大幅度降低。力学性能测试结果表明,LGFPP/IFR体系的拉伸强度、弯曲强度以及缺口冲击强度因OMMT的添加,分别提高了8.15%、9.04%和24%,使LGFPP/IFR体系中由于IFR引起LGFPP力学性能降低的弊端得到了明显改善。