水滑石对PBS/Sb2O3阻燃PA6/GF性能的影响

研究了聚溴化苯乙烯(PBS)对玻纤增强尼龙6(PA6/GF)阻燃和力学性能的影响,并采用锥形量热仪研究了改性水滑石(HT)对PBS/Sb2O3阻燃PA6/GF抑烟作用和燃烧时热释放速率的影响。结果表明,随PBS用量增加,PA6/GF的氧指数增加,阻燃性提高,当PBS质量分数为20%时,PA6/GF的垂直燃烧达到FV-0级;HT燃烧后形成多孔、大比表面积的镁铝复合氧化物,能够有效吸附材料燃烧过程中产生的炭微粒,对PBS/Sb2O3阻燃PA6/GF具有显著的抑烟作用。当HT质量分数为5%时,烟释放速率降低27.6%,且对阻燃PA6/GF的力学性能影响不大。另外,HT使PA6/GF的氧指数和相比漏电起痕指数(CTI)提高。     

三聚氰胺氰尿酸盐/氧化锑/石墨烯复合阻燃玻璃纤维增强聚酰胺6复合材料

研究了阻燃剂三聚氰胺氰尿酸盐（MCA）/氧化锑（Sb2O3）和石墨烯（GP）对玻璃纤维（GF）增强聚酰胺6（PA6）复合材料性能的影响。结果表明,MCA/Sb2O3（质量比为70/30）的加入改善了PA6和GF的相容性,与不添加阻燃剂的PA6/GF相比,当MCA/Sb2O3含量为30份时,复合材料的强度、刚性和阻燃性能显著提高;GP的加入对PA6/GF的力学性能影响不大,但阻燃性能明显提高,当GP的含量为0.3份时,复合材料的极限氧指数达到30.1 %,阻燃等级达到UL 94 V-0级;GP在PA6/GF的燃烧过程中具有促进炭化和发泡双重作用。     

滑石粉对PA6/MCA体系阻燃性能的影响

研究了滑石粉对聚酰胺6/三聚氰胺氰尿酸盐(PA6/MCA)体系阻燃性能及阻燃机理的影响。燃烧测试结果表明:当滑石粉含量为25 phr时,PA6/MCA/滑石粉复合材料的极限氧指数(LOI)达到28.5%,垂直燃烧测试(UL 94)达到V-0级,相比于PA6/MCA体系均有所提高;同时,燃烧后的试样表面形成了连续、致密的保护层。热重(TG)分析结果表明:滑石粉的引入使PA6/MCA体系的热稳定性下降,但是提高了其质量保留率,而残留的不燃物质起到了凝聚相阻燃作用。傅里叶变换红外光谱(FTIR)分析表明:加入了滑石粉的PA6/MCA体系,其燃烧生成的Si—O—C基团富集在材料表面,有利于形成致密的保护层,从而抑制材料的燃烧。     

氧化铁协效次磷酸盐阻燃增强PA66的研究

以次磷酸盐阻燃增强尼龙66(PA66)产品为体系,研究了氧化铁(Fe2O3)对体系阻燃性能的影响,通过锥形量热仪分析、热失重分析以及形貌分析,发现Fe2O3对次磷酸盐阻燃增强PA66体系有明显的促进分解作用,稳固炭化层,有效阻隔可燃气体的释放及热量的传递,显著降低体系的热释放速率峰值。当Fe2O3添加量为0.5%、次磷酸盐为15%时,该体系阻燃可以达到UL94 V-0。     

三聚氰胺氰尿酸盐阻燃玻纤增强和碳酸钙填充尼龙66

采用三聚氰胺氰尿酸盐(MCA)阻燃玻纤(GF)增强和碳酸钙填充尼龙66(PA66)。研究表明:MCA可加速MCA/GF/PA66中尼龙降解,降低熔体黏度,材料在燃烧温度下熔体流动性高,可形成快速熔滴脱离火源而迅速自熄;而MCA/CaCO3/PA66中碱性CaCO3会吸收MCA分解的氰尿酸,尼龙降解作用减弱,可保持较高熔体黏度,熔滴速度慢,不自熄。由于玻纤紧密嵌入增强炭层并使其致密化,玻纤增强体系较碳酸钙体系具有更好成炭性。     

二乙基次膦酸铝和三聚氰胺氰尿酸盐对PA6的协同阻燃作用

通过极限氧指数(LOI)测定、垂直燃烧试验和锥型量热分析研究了二乙基次膦酸铝(ADEP)和三聚氰胺氰尿酸盐(MCA)对聚酰胺6(PA6)的协同阻燃作用。结果表明ADEP和MCA对PA6具有良好的协同阻燃作用;热失重分析结果表明添加ADEP,MCA和ADEP/MCA均降低PA6的热稳定性,但ADEP/MCA的影响较小;残余物分析结果证实ADEP主要是通过气相产生阻燃作用,在燃烧过程中,通过捕获燃烧产生的自由基而抑制燃烧;MCA分解成挥发性CO2和NH3等惰性气体,通过燃料稀释作用而产生阻燃。     

聚磷酸酯三聚氰胺在玻璃纤维增强尼龙6中的阻燃性能研究

以聚磷酸酯三聚氰胺(MPP)、改性烷基苯酚甲醛树脂(MAR)为阻燃剂,通过二者之间的协同效应改善尼龙6/玻璃纤维(PA6/GF)复合材料的阻燃性能。采用熔融共混法制备了添加不同MPP/MAR用量的PA6/GF复合材料,通过测定极限氧指数(LOI)、垂直燃烧等级、炭层形貌研究了二者的协同阻燃机理,并测试了PA6/GF复合材料的力学性能。结果表明:当MPP/MAR用量比为10/10时,LOI达到最大值29.3%,垂直燃烧等级为V-0级,热释放速率最低,仅为116.3 kW/m~2;添加MPP及MAR对于提高PA6/GF复合材料的力学性能具有一定作用。     

溴代三嗪阻燃剂对LGF/PA6复合材料阻燃机理及降解行为的影响

利用溴代三嗪(BrN)协同三氧化二锑(Sb2O3)制备N-Br-Sb阻燃长玻纤增强尼龙6复合材料(BrN/LGF/PA6),通过极限氧指数(LOI)、垂直燃烧(UL94)、热重分析法(TGA)、锥形量热分析(CONE)、红外光谱分析(FTIR)、扫描电镜(SEM)等方法研究了BrN协同Sb2O3对长玻纤增强尼龙6复合材料阻燃性能影响.结果表明,在BrN与Sb2O3的协效阻燃体系添加量为16％时,可使BrN/LGF/PA6复合材料的阻燃等级达到FV-0级,LOI为26.9％.锥形量热与热失重分析均表明,BrN协同Sb2O3能提高BrN/LGF/PA6复合材料的高温下热稳定性,促进PA6分解成炭,从而起到良好的阻燃作用.红外光谱、扫描电镜和锥形量热分析表明,LGF/PA6与BrN/LGF/PA6复合材料热处理后的炭层结构不完全相同,说明了BrN协同Sb2O3不仅在气相发挥阻燃作用,在固相也同样发挥阻燃作用.     

MCA/MH对PA6热降解行为影响的研究

用热重分析仪(TG)、傅立叶红外光谱分析仪(FTIR)、扫面电镜(SEM)表征了三聚氰胺尿酸盐(MCA)/氢氧化镁(MH)/聚酰胺6(PA6)三元复合体系的热降解行为、降解产物的红外结构以及燃烧产物的炭层结构。结果表明,MCA/MH二元体系降低了PA6的初始分解温度,改变了PA6的热降解途径,降解过程产生三嗪类物质,有利于体系热稳定性的提高。MH提高了体系燃烧的成炭率,有利于阻燃性的提高。     

无机填料对PA6/MCA阻燃复合材料性能的影响

研究了不同种类的无机填料(硅灰石、碳酸钙)对尼龙6(PA6)/三聚氰胺氰尿酸盐(MCA)阻燃复合材料性能的影响。阻燃性能测试结果表明,PA6/MCA/硅灰石阻燃复合材料为UL94 V–0级,比PA6/MCA阻燃复合材料(V–2级)有显著提高;然而PA6/MCA/碳酸钙阻燃复合材料的极限氧指数却有所下降。扫描电子显微镜测试分析表明,PA6/MCA/硅灰石阻燃复合材料燃烧后的表面炭层呈连续、致密状;PA6/MCA/碳酸钙阻燃复合材料的表面炭层有很多孔洞,且孔洞直径大。傅立叶变换红外光谱测试结果表明,PA6/MCA/硅灰石阻燃复合材料的表面炭层与Si O2能很好地结合,形成致密的保护层,致使其阻燃性能显著提高。另外,力学性能测试结果表明,硅灰石能够提高PA6/MCA阻燃复合材料的拉伸强度,但降低了缺口冲击强度,而碳酸钙的加入却使得PA6/MCA阻燃复合材料的综合力学性能有所下降。     

A phosphorus‐containing inorganic compound as an effective flame retardant for glass‐fiber‐reinforced polyamide 6

A novel inorganic compound, aluminum hypophosphite (AP), was synthesized successfully and applied as a flame retardant to glass‐fiber‐reinforced polyamide 6 (GF–PA6). The thermal stability and burning behaviors of the GF–PA6 samples containing AP (flame‐retardant GF–PA6) were investigated by thermogravimetric analysis, vertical burning testing (with a UL‐94 instrument), limiting oxygen index (LOI) testing, and cone calorimeter testing (CCT). The thermogravimetric data indicated that the addition of AP decreased the onset decomposition temperatures, the maximum mass loss rate (MLR), and the maximum‐rate decomposition temperature of GF–PA6 and increased the residue chars of the samples. Compared with the neat GF–PA6, the AP‐containing GF–PA6 samples had obviously improved flame retardancy: the LOI value increased from 22.5 to 30.1, and the UL‐94 rating went from no rating to V‐0 (1.6 mm) when the AP content increased from 0 to 25 wt % in GF–PA6. The results of CCT reveal that the heat release rate, total heat release, and MLR of the AP‐containing GF–PA6 samples were lower than those of GF–PA6. Furthermore, the higher additive amount of AP affected the mechanical properties of GF–PA6, but they remained acceptable. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

聚酰胺6在聚丙烯/微胶囊化多聚磷酸铵中的作用

选用聚酰胺6（PA6）作为聚丙烯（PP）/微胶囊化多聚磷酸铵(MAPP)的协效成炭剂,可提高PP/MAPP的阻燃性能和力学性能。结果表明,MAPP/PA6=25/3(质量比,下同）时,膨胀度达到180.23㎝3/g,剩炭率达到72.11 ％,分别比MAPP的78.6㎝3/g和61.96 ％增大了1.3倍和0.6倍。热分析表明,添加PA6后,阻燃PP在低温区的失重速度降低,剩炭率明显提高,有利于PP的阻燃;但在高温区剩炭降解速率加快,释出更多的可燃物燃烧,放出的大量热对提高阻燃性能不利。因此PA6添加量应适量。当PP/MAPP/羟基化聚丙烯（EPP）/PA6 (75/25/7/3时,IFR-PP氧指数增加到34.7 %,水平燃烧16 s自熄,同时拉伸强度增加到28.89 MPa。     

The effect of morphology on the flame‐retardant behaviors of melamine cyanurate in PA6 composites

Three types of melamine cyanurate (MCA) with micrometer‐size sphere‐like, micrometer‐scale rod‐like, and nanometer‐scale flake‐like morphologies were synthesized by changing the chemical circumstances of the reactions. The microcosmic morphologies of MCA were characterized via scanning electron microscopy and X‐ray diffraction. After the MCAs with different morphologies were incorporated into polyamide 6 (PA6), the flame‐retardant properties of the MCA/PA6 composites were investigated using the limited oxygen index (LOI), UL94, and cone calorimeter tests. The MCA/PA6 composites with nanometer‐scale flake‐like MCA obtained an LOI value of 29.5% and a UL94 V‐0 rating, which were higher than those with micrometer‐size sphere‐like and rod‐like MCAs. However, the different morphologies did not affect the heat release rate, total smoke release, average carbon monoxide yield, and average carbon dioxide yield based on the cone calorimeter. The flame‐retardant mechanism of MCAs with different morphologies was investigated via thermal gravimetric analysis (TGA) and TGA‐Fourier transform infrared spectra. The results show that the different morphologies of MCA resulted in different dispersed evenness of MCA. Further, the nanometer‐scale flake‐like morphology of MCA brought more interactions of hydrogen bond between MCA and PA6, which resulted in the delay of MCA decomposition and the enhancement of MCA flame‐retardant effect. The nanometer‐scale flake‐like MCA had a better performance compared with the other samples because of the delaying and even release of flame‐retardant effect by the decomposition of evenly dispersed MCA. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40558.     

尼龙基MCA母粒的制备及其在阻燃尼龙的应用

针对三聚氰胺氰尿酸盐(MCA)粉体对尼龙(PA)进行阻燃改性时,MCA分散性差,材料阻燃性能不稳定的问题,运用特殊的包覆工艺成功制得了PA基MCA母粒。将制得的MCA母粒及MCA粉体分别与PA6或PA66共混挤出,制得阻燃PA材料。对比分析了MCA母粒及MCA粉体阻燃PA6或PA66的垂直燃烧性能和力学性能。结果表明,与MCA粉体相比,MCA母粒可在MCA含量较低的情况下使厚度为0.8 mm及1.6 mm的阻燃PA6或PA66试样的垂直燃烧等级达到V–0级。MCA母粒及粉体对阻燃PA6的弯曲强度和PA66的拉伸强度影响很小,MCA母粒阻燃PA6的拉伸强度较粉体阻燃的高,而阻燃PA66的弯曲强度低;MCA母粒使阻燃PA的缺口冲击强度降低,而MCA粉体对PA的缺口冲击强度影响较小,当MCA含量较低时,MCA母粒阻燃PA的缺口冲击强度明显高于MCA粉体阻燃的PA。制备的MCA阻燃母粒对PA的阻燃效果不受黑色母料的影响,且具有较好的阻燃稳定性。     

硅锡协同阻燃尼龙6

采用氯化亚锡(SnCl2)/聚氨丙基苯基倍半硅氧烷(PAPSQ)复合阻燃剂阻燃改性尼龙6(PA6)。测定了阻燃PA6的氧指数(LOI),利用锥形量热仪测定了阻燃PA6的释热速率、总释热量、有效燃烧热等多种阻燃参数,并用扫描电镜(SEM)观察了阻燃PA6残炭的形貌。实验表明,当SnCl2用量为4%,PAPSQ用量为1%时,PA6的LOI为31%,PA6的释热速率、总释热量和有效燃烧热均明显下降,PAPSQ对SnCl2有协同阻燃效果。     

Comparison of the effects of phenyl dichlorophosphate modified and unmodified β‐iron(III) oxide hydroxide on the thermal,combustion, and mechanical properties of ethylene–vinyl acetate/magnesium hydroxide composites

The objective of this study was to compare the impact of β‐iron(III) oxide hydroxide [β‐Fe(O)OH] and iron hydroxide modified with phenyl dichlorophosphate [β‐Fe(O)OPDCP] on the thermal, combustion, and mechanical properties of ethylene–vinyl acetate (EVA)/magnesium hydroxide (MH) composites. For the EVA/MH composites in combination with these iron‐containing co‐additives, β‐Fe(O)OH and β‐Fe(O)OPDCP both led to an increase in the thermal stability at higher temperatures. The results of microscale combustion calorimetry indicate that the peak heat‐release rate, total heat release, and heat‐release capacity, which are indicators of a material fire hazard, all decreased. Moreover, significant improvements were obtained in the limiting oxygen index (LOI) and Underwriters Laboratories 94 ratings. However, the EVA4 system reached a V‐0 rating, whereas the EVA3 system reached a V‐2 rating. The LOI values for the EVA3 and EVA4 systems were 35 and 39, respectively. A homogeneous and solid structure of char residue caused by β‐Fe(O)OPDCP was observed by scanning electron microscopy. Furthermore, because of the good interfacial compatibility between the fillers and the EVA matrix, the EVA4 system presented better mechanical properties than the EVA3 system. Thermogravimetric analysis/IR spectrometry showed that β‐Fe(O)OPDCP reduced the combustible volatilized products of EVA/MH. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40112.     

Preparation and Combustion Properties of Flame Retardant Nylon 6/Montmorillonite Nanocomposite

Flame retardant Nylon 6 (PA6)/montmorillonite (MMT) nanocomposites have been prepared using direct melt intercalation technique by blending PA6, organophilic clay and conventional fire retardants, such as the melamine cyanurate (MCA) and the combination of decabromodiphenyl oxide (DB) and antimony oxide (AO). Their morphology and combustion properties are characterized by XRD, transmission electron microscopy (TEM), UL‐94 test and Cone Calorimeter experiments. The flame retardant nanocomposites with MCA or DB and AO show lower heat release rate (HRR) peak compared to that of conventional flame retardant PA6. Meanwhile, the synergetic effect was studied between clay and DB‐AO.

TEM of PA‐n nanocomposite.     

Preparation and characteristics of polypropylene/nylon/montmorillonite flame retardant nanocomposites

Abstract

In this paper, nylon was used as carbonisation agent instead of pentaerythritol (PT), and the melt intercalation method was used to synthesise polypropylene (PP)/nylon (PA6)/montmorillonite (MMT) flame retardant nanocomposites. The structure and flammability property of products were characterised by X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, thermogravimetric analysis (TGA), cone calorimeter test, limiting oxygen index and vertical burning test. The results showed that the polymer chain was intercalated into the MMT's interlayer and the MMT dispersed into PP/PA6 matrix in the form of intercalation to get flaky texture. The appropriate content of MMT in composition is 4–6 mass%. The use of intercalated MMT increased the tensile strength of materials by 15·0% and the impact strength by 69·5%, and improved the flame retardant properties. The TGA showed that the char residue rate reached 12·3%. The cone calorimeter experiments indicated that the peak of heat release rate reduced by about 87% in comparison with the pure PP and the residue weight increased. The vertical burning test (UL 94) results indicated that the materials achieved V-0 grade.