MPP/PER/APP阻燃PP的阻燃及热裂解行为

采用聚磷酸蜜胺(MPP)／季戊四醇(PER)／聚磷酸铵(APP)三元膨胀型阻燃剂(IFR)阻燃聚丙烯(PP),测定了阻燃PP的极限氧指数(LOI)、UL94V阻燃性及热稳定性,以傅里叶变换红外光谱(FTIR)分析了阻燃PP的热分解残余物。以锥形量热仪(CONE)测定了阻燃PP的诸多与火灾有关的阻燃参数,包括释热速度、质量损失速度、总释热量、有效燃烧热、比消光面积及引燃时间等,以光电子能谱(XPS)测定了阻燃PP残炭表面的元素组成及XPS曲线拟合数据,还以扫描电镜(SEM)观测了阻燃PP残炭的形态。     

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。     

八钼酸蜜胺的制备、表征及阻燃协同、抑烟性能

报道了以蜜胺(MA)和七钼酸铵(AHM)制备八钼酸蜜胺的方法,即在搅拌下将1kgMA分批加入盛有1L水的反应器中,再加入1 5kg浓盐酸,加热使MA全部溶解。另外将2 2kgAHM溶于热水中,将所得水溶液再加入MA的盐酸溶液中,生成八钼酸蜜胺(MOM)白色粉末,得率大于95%。用傅里叶变换红外光谱(FTIR)、热失重分析(TGA)、光电子能谱(XPS)及元素分析对标题化合物进行了表征。极限氧指数和UL94V阻燃性能测试表明,聚酰胺6(PA6)中加入质量分数25%的聚磷酸蜜胺(MPP),阻燃PA6的氧指数为29 6,通过UL94V-1阻燃级。如PA6中再加入质量分数2 0%的MOM,由于MOM的阻燃协同效应,阻燃PA6的氧指数可达35 3,通过UL94V-0阻燃级。实验还证明,在聚丙烯(PP)中加入质量分数1%的MOM,PP的阴燃最大烟密度降低50%以上。     

ABS树脂的无卤膨胀阻燃研究

以聚酰胺6(PA6)为协效成炭剂,将膨胀型阻燃剂聚磷酸铵(APP)应用于ABS树脂,通过氧指数(OI)测定及UL94测定,探讨了PA6、APP含量对阻燃体系阻燃性能的影响;同时,对复合体系进行了热失重分析,并采用扫描电镜(SEM)观察了复合物燃烧后炭层结构。结果表明:PA6的加入明显提升了体系成炭率,降低了最大热失重速率,ABS/PA6/APP体系燃烧表面形成了膨胀、均匀、致密的炭层结构。当PA6/ABS=20/80时,阻燃性能最佳,当APP含量为25%时,OI可以达到30%,UL94测定达V—1级;当APP含量为35%时,UL94测定达V—0级。     

三聚氰胺氰尿酸盐阻燃尼龙6的机理研究

将蒙脱土(MMT)引入反应性挤出制备三聚氰胺氰尿酸盐(MCA)阻燃尼龙6(PA6)体系中.研究了其阻燃性能及MCA阻燃PA6的阻燃机理,MCA阻燃PA6机理主要是MCA分解产物催化PA6为齐聚物,形成熔滴,带走燃烧产生的热量,使材料自熄.     

二丙基次膦酸铝和氢氧化镁对PA6的复合阻燃作用

通过极限氧指数测定、垂直燃烧实验和锥形量热分析研究了二丙基次膦酸铝(ADPP)和氢氧化镁(MH)对尼龙6(PA6)的复合阻燃作用。结果表明:ADPP与MH对PA6无协同阻燃作用,ADPP复配少量的MH(质量分数10%)阻燃PA6的LOI和垂直燃烧级别变化不大,总热释放量(THR)和最高热释放速率(PHRR)略有增加,但热稳定性有明显改善。残余物分析结果表明,复合少量的MH略增加了材料的成炭性,但炭层结构变得比较松散,因而对ADPP阻燃PA6的影响不大。而随着MH用量增加,成炭性明显下降,因而降低了ADPP对PA6的阻燃作用。     

次磷酸铝/环氧硅树脂阻燃PA6的性能研究

将次磷酸铝(AHP)和环氧硅树脂(ESR)复配后添加到聚酰胺6(PA6)中制备了阻燃PA6材料。通过极限氧指数(LOI)和垂直燃烧(UL 94)测试研究了该阻燃PA6材料的阻燃性能,利用扫描电子显微镜(SEM)观察了阻燃PA6的残炭形貌,同时还通过拉伸、弯曲和冲击强度测试考察了阻燃PA6的力学性能。结果表明:当AHP用量为24%时,阻燃PA6材料通过了UL 94V-0测试,其LOI值达到25.6%;而以质量比为95:5的复配阻燃剂AHP/ESR对PA6进行阻燃,且阻燃剂用量仅为18%时,阻燃PA6材料通过UL 94V-0测试,其LOI值达到25.8%,这说明AHP与ESR对PA6具有良好的协效阻燃作用。与PA6/AHP复合材料相比,PA6/AHP/ESR复合材料的力学性能有所改善,这说明ESR的加入可提高材料的力学性能。此外,SEM测试结果显示,ESR的加入有助于阻燃PA6材料形成均一、致密的炭层,对下层的材料起到了很好的保护作用,从而提高了材料的阻燃性能。     

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。     

高磷含量聚酯多元醇的制备及其在阻燃PA6中的应用

以苯基膦酰二氯(BPOD)和双羟甲基甲基氧化磷(BMPO)为原料,制备了一种高含磷聚磷酸酯多元醇阻燃剂(PHPOP),并通过红外光谱(FTIR)和热重分析(TGA)表征了产物的结构及热稳定性。采用熔融共混法制备了PHPOP阻燃的聚酰胺6(PA6)材料,通过极限氧指数(LOI)法和垂直燃烧法测试了材料的阻燃性能,并采用热重分析仪考察了阻燃PA6的热分解过程及其成炭性能,随后采用扫描电镜(SEM)对其炭层形貌进行了观察。结果表明:阻燃剂PHPOP对PA6具有良好的阻燃效果。当20%阻燃剂的加入即可使PA6的LOI由21.2%提高至27.5%,并通过UL 94V-0级测试。热降解及炭层形貌分析结果表明,PHPOP的添加对PA6在降解过程中的成炭具有良好的促进作用,使炭层致密性提高,阻碍了热和可燃气体的传递,从而提高了PA6材料的阻燃性能。     

尼龙增强膨胀型阻燃PP的研究

用尼龙6(PA6)代替部分季戊四醇(PT)作成炭剂，制得了膨胀型阻燃聚丙烯(IFR-PP)，讨论了PA6对IFR-PP的力学性能、阻燃性能、热稳定性和流变行为的影响。结果表明：PA6的加入提高了IFR-PP的表观粘度、力学性能和热稳定性。PA6的用量为3％时，IFR-PP的拉伸强度提高了24．2％，分解温度提高了18℃；同时阻燃性能保持不变，且具有良好的加工性能。     

塑料在燃烧条件下裂解行为的研究

采用锥形量热仪对几种常用塑料的燃烧裂解行为进行了研究，分析比较了典型塑料材料在不同辐射功率下燃烧裂解的变化规律，以及不同阻燃体系对塑料燃烧裂解行为的影响。探讨了火灾条件下塑料燃烧裂解的原因，以及某些阻燃体系的阻燃作用。     

Red phosphorus–controlled decomposition for fire retardant PA 66

The thermal degradation and the combustion behavior of glass fiber–reinforced PA 66 materials containing red phosphorus were investigated. Thermogravimetry (TG), TG coupled with FTIR, and TG coupled with mass spectroscopy were used to investigate the thermal decomposition. The flame retardant red phosphorus was investigated with respect to the decomposition kinetics and the release of volatile products. The combustion behavior was characterized using a cone calorimeter. Fire risks and fire hazards were monitored versus external heat fluxes between 30 and 75 kW/m². Red phosphorus acts in the solid phase and its efficiency depends on the external heat flux. The use of red phosphorus results in an increased amount of residue and in a corresponding decrease in total heat release. The decrease of the mass loss rate peak results in a corresponding decrease of the peak heat release. With increasing external heat flux applied the first effect on the total heat release decreases linearly, whereas the second effect on the peak heat release expands linearly. The investigation provides insight into the mechanisms of how the fire retardant PA 66 is achieved by red phosphorus controlling the degradation kinetics. Taking into account that a decrease of the volatile products also leads to a decrease of heat production in the flame zone and that the char acts as heat transfer barrier, a reduced pyrolysis temperature is suggested as a further feedback effect. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2060–2071, 2002     

聚铝硅氧烷对聚碳酸酯的阻燃作用

采用水解缩合法制备了聚铝硅氧烷,用极限氧指数、热失重分析、扫描电子显微镜、X射线光电子能谱研究了聚铝硅氧烷对聚碳酸酯（PC）的阻燃作用机理。结果表明,聚铝硅氧烷可明显提高PC的极限氧指数;在热降解过程中,聚铝硅氧烷可使PC的最大热降解速率降低,800 ℃残炭率显著提高,在PC中添加5 %（质量分数,下同）的聚铝硅氧烷可使PC的800 ℃残炭率提高44.1 %;在燃烧过程中,聚铝硅氧烷会迁移到PC表面,与PC的降解产物发生相互作用,促进残炭的形成,硅(Si)和铝(Al)积聚在材料表面形成富含Si、Al的绝缘炭层,抑制了材料的进一步降解,阻碍了热量和可燃性气体的传递,从而有效地改善了PC的阻燃性能。     

Flame retardant properties of polyamide 6 with piperazine pyrophosphate

Piperazine pyrophosphate (PAPP) was mixed in polyamide 6 (PA6) to investigate its flame retardant properties. The PAPP was characterised by Fourier transform infrared (FT-IR), elemental analysis, proton nuclear magnetic resonance (1H-NMR) spectroscopy and thermogravimetric analysis (TGA). The elemental analysis and TGA results of PAPP indicated it had a high P element content and good thermal stability. The flame retardancy of PA6/PAPP was also characterised by TGA, limiting oxygen index (LOI), UL-94 vertical test and microscale combustion calorimetry (MCC). The TGA results showed that the PAPP increased the stability of the PA6/PAPP and resulted in a significant increase of char residue. PA6/PAPP passed the UL94 V-0 rating with a LOI value of 42 vol %. The MCC test indicated that the PAPP can greatly decrease the peak heat release rate (PHRR) and total heat release (THR). The results of scanning electron microscope (SEM) illustrated that PAPP can promote the formation of compact char layer.     

次磷酸盐⁃环四硅氧烷双基化合物复配二乙基次磷酸铝对PA6的阻燃性能研究

将次磷酸盐?环四硅氧烷双基化合物（MVC?AlPi）与二乙基次磷酸铝（AlPi）复配阻燃聚酰胺6（PA6）。目的是考察外加的富磷酸铝化合物中磷酸铝基团和环四硅氧烷基团之间的配比对PA6阻燃效率的影响。结果表明, PA6/8.8 %AlPi/2.2 %MVC?AlPi具有协同屏障效应,可使复合材料的极限氧指数（LOI）值提高到31.5 %,并通过UL 94 V?0级别。相比于纯PA6,PA6/8.8 %AlPi/2.2 %MVC?AlPi的热释放速率峰值（PHRR）降幅近50 %、总热释放量（THR）也降低了15 %,PA6/8.8 %AlPi/2.2 %MVC?AlPi的残炭率虽略低于11 %MVC?AlPi,却形成了内层坚硬,外层类陶瓷化的双层炭层结构,MVC?AlPi、AlPi与PA6的相互作用可以锁定更多P、C碎片,促进由含硅富磷残渣组成的屏障保护炭层的形成。在阻燃剂添加总量不变的情况下,通过调节各组分的比例,发挥出更好的协同阻燃效果。     

Flame Retardant Functionalization of Microcrystalline Cellulose by Phosphorylation Reaction with Phytic Acid

The functionalization of microcrystalline cellulose (MCC) is an important strategy for broadening its application fields. In the present work, MCC was functionalized by phosphorylation reaction with phytic acid (PA) for enhanced flame retardancy. The conditions of phosphorylation reaction including PA concentration, MCC/PA weight ratio and temperature were discussed, and the thermal degradation, heat release and char-forming properties of the resulting PA modified MCC were studied by thermogravimetric analysis and pyrolysis combustion flow calorimetry. The PA modified MCC, which was prepared at 90 °C, 50%PA and 1:3 weight ratio of MCC to PA, exhibited early thermal dehydration with rapid char formation as well as low heat release capability. This work suggests a novel strategy for the phosphorylation of cellulose using PA and reveals that the PA phosphorylated MCC can act as a promising flame retardant material.     

Investigation of the influence of red phosphorus,expansible graphite and zinc borate on flame retardancy and wear performance of glass fiber reinforced PA6 composites

The flame retarded materials were prepared which used wear‐resistant PA6 composite (PA6/GF/PTFE/UHMWPE/CG, 85/15/5/5/5 by weight) as matrix, red phosphorus (RP), expansible graphite (EG), and zinc borate (ZB) as fire retardant. The flame retarded properties were characterized by LOI and UL‐94 testing. PA6 composite with 15 wt% RP reached V0 rating and had a high LOI value (27.3 vol%). When a combination of 7 wt% ZB and 8 wt% RP was added, increases in LOI (27.9 vol%) and UL‐94 rating(V0) were both observed. Thermogravimetric analysis (TGA) and char residue characterization showed that the combination of RP and ZB can promote the formation of char barrier, reduce the mass loss rate, and thus improve the flame retardancy of PA6 composites. The wear test showed that, the composite filled by 15 wt% RP or a combination of 7 wt% ZB and 8 wt% RP both possessed a low wear rate and a much stable friction coefficient. The presence of EG could also improve the flame retardance but was harmful to the mechanical property as well as wear performance. The results indicated that ZB and RP had synergy effect on improving both flame retardance and wear performance of PA6 composites. POLYM. COMPOS., 38:2090–2097, 2017. © 2015 Society of Plastics Engineers     

Influence of char-forming lignin in combination with aluminium phosphinate on thermal stability and combustion properties of polyamide 11 blends

Polyamide 11 (PA) blends based on char-forming industrial lignin and aluminum phosphinate (AlP) were prepared to improve flame retardant (FR) properties using a green and eco-friendly approach. This study investigates the thermal degradation and combustion behavior of PA blends prepared by using AlP in combination with two different types of industrial lignins (i.e., kraft lignin (DL) and lignosulphonate lignin (LL). Thermogravimetric (TG) analysis showed that ternary blends containing LL and AlP developed higher char residue up to 10.7 wt% upon decomposition in inert atmospheres. The combination of lignin and AlP increases the thermal stability by shifting the initial decomposition temperature (T_5%) and temperature at maximum decomposition (T_max) to a higher temperature range, attributed to the stabilization of decomposition products. Furthermore, combustion behavior studied by cone calorimeter (forced combustion) and pyrolysis combustion flow calorimeter (PCFC) tests presented a significant reduction in the peak of heat release rate (PHRR) and total heat release (THR). It was found that LL and AlP-containing blends more effectively decreased fire parameters like PHRR and THR than that of DL and AlP-containing blends. The best interaction with reduced fire-retardant properties was obtained when 10 wt% loading of lignin (DL/LL) and AlP was used. The reduction in heat release parameters was mainly ascribed to the condensed phase mechanism by forming an efficient protective char layer, which acts as a barrier against heat and mass transfer between the condensed and the gas phases. Raman spectroscopy analysis also confirmed the formation of the protective graphitic layer in the condensed phase.