无卤膨胀复合阻燃低密度聚乙烯/乙烯-醋酸乙烯酯共混物的研究

分别采用三聚氰胺氰尿酸盐(MCA)、微胶囊红磷(MCP)以及氢氧化镁[Mg(OH)2]等与膨胀型阻燃剂PNP进行复配,研究了不同阻燃剂及其配比对低密度聚乙烯/乙烯-醋酸乙烯酯(PE-LD/EVA)共混物的阻燃和力学性能的影响。结果表明,在PE-LD/EVA为70/30的基体树脂中,当复合阻燃剂的含量为35%时,PNP/MCA的最佳配比为3/2,阻燃材料的极限氧指数为30.8%;PNP/MCA/MCP的最佳比例为24/16/4,阻燃材料极限氧指数为32.3%;PNP/MCA/MCP/Mg(OH)2的最佳比例为24/16/4/22,阻燃材料的极限氧指数为30.9%,垂直燃烧达到UL 94V-0级,拉伸强度为11.1MPa,断裂伸长率为80.6%。     

Mg（OH）2/Al（OH）3阻燃电缆护套料性能的研究

采用低密度聚乙烯/乙烯-醋酸乙烯/三元乙丙橡胶(PE-LD/EVA/EPDM)共混物为电缆护套料的基材,分别以复配的氢氧化镁/氢氧化铝[Mg(OH)2/Al(OH)3]和单组分的Mg(OH)2为阻燃体系,研究了这两种阻燃体系对材料的阻燃性能和力学性能的影响。结果表明,随着Mg(OH)2/Al(OH)3比例的增大,材料的拉伸强度和极限氧指数增加,但断裂伸长率不断下降;在以Mg(OH)2为阻燃剂的体系中,材料的极限氧指数与Mg(OH)2的添加量成正比,而拉伸强度和断裂伸长率与其成反比,当Mg(OH)2的添加量在40～50份时,材料的极限氧指数能够达到29%以上,力学性能也优于Mg(OH)2/Al(OH)3体系阻燃的材料。     

化学交联EVA/NBR阻燃复合材料的燃烧行为及力学性能

以乙烯-醋酸乙烯共聚物（EVA）/丁腈橡胶（NBR）为主体,氢氧化镁[Mg(OH)2）]和红磷（RP）为阻燃剂制备了无卤阻燃EVA/NBR复合材料,通过力学性能测试、热重分析以及燃烧行为表征（极限氧指数和锥形量热分析）研究了交联剂过氧化二异丙苯（DCP）以及马来酸酐接枝乙烯-醋酸乙烯共聚物（EVA-g-MAH）对EVA/NBR复合材料的力学性能、热稳定性和阻燃性能的影响。结果表明,含有10份相容剂EVA-g-MAH的交联材料,其拉伸强度可达到17.4 MPa,断裂伸长率可达到1236 %;材料的热分解温度从321.6 ℃提高到327.0 ℃,残炭量从10 %提高到了32.1 %;极限氧指数达到33.5 %且热释放速率峰值从941 kW/m2降到了690 kW/m2;通过扫描电子显微镜对复合材料的断面形貌进行了观察分析,发现材料断裂表面填料分散均匀。     

Al（OH）3和Mg（OH）2阻燃EVA性能的研究

选用形貌、粒径尺寸及分布相近的两种无机阻燃剂氢氧化铝（Al（OH）3）和氢氧化镁（Mg（OH）2），研究了二者用量对乙烯-醋酸乙烯酯共聚物（EVA）复合材料的力学性能和阻燃性能的影响，并比较了添加红磷的复合材料的力学性能和阻燃性能。研究表明：Al（OH）3和Mg（OH）2用量对复合材料性能影响比较相似，随着阻燃剂用量的增加，复合材料的阻燃性能提高，拉伸强度增加，但断裂伸长率下降；通过锥形量热仪数据看出：Al（OH），的点燃时间短，最大热释放速率和平均热释放速率低，火行为指数大，阻燃效果比Mg（OH）2好；红磷的加入对复合材料力学性能影响不大，而对阻燃性能影响较大。Mg（OH）2与红磷复配能提高复合材料的氧指数，但是，从水平和垂直燃烧角度考虑，Al（OH）3与红磷之间的阻燃协效效果更好。     

4A分子筛和SiO2对EVA/IFR复合材料性能的影响

以聚磷酸铵(APP)复配季戊四醇(PER)为膨胀型阻燃剂(IFR)制备了无卤阻燃乙烯-醋酸乙烯共聚物(EVA)/IFR复合材料,通过极限氧指数仪、热失重分析仪及扫描电子显微镜研究分析了4A分子筛和SiO2的加入对复合材料阻燃性能、热稳定性能及复合材料残炭表面形貌的影响。结果表明,加入4A分子筛可以明显提高复合材料的极限氧指数,当添加1份4A分子筛时,复合材料的极限氧指数达到31%,比未添加时提高了2%;4A分子筛的加入使复合材料在燃烧过程出现熔融滴落现象;继续加入SiO2可以进一步提高复合材料的极限氧指数,当添加3份SiO2时,复合材料的垂直燃烧测试达到V-0级。     

硅酸盐纳米短纤维增强EVA复合材料的阻燃和力学性能

以氢氧化镁[Mg(OH)2]和微胶囊红磷（MRP）为阻燃剂制备了无卤阻燃乙烯-醋酸乙烯共聚物（EVA）复合材料。通过极限氧指数、热失重分析和力学性能研究了硅酸盐纳米短纤维 (SNF) 以及马来酸酐接枝乙烯-醋酸乙烯共聚物（EVA-g-MAH）的加入对EVA阻燃性能和力学性能的影响,并通过扫描电子显微镜对其断面形貌和残炭表面形貌进行了观察和分析。结果表明,加入适量的EVA-g-MAH可以提高复合材料的极限氧指数和力学性能,加入12份的EVA-g-MAH后,材料的拉伸强度可达到10.2 MPa,断裂伸长率达到521 %,极限氧指数为39%,垂直燃烧达到V-0级别;加入适量的SNF后,可以显著提高复合材料的拉伸强度,当添加20份的SNF后,复合材料各性能最优,拉伸强度为12.3 MPa,断裂伸长率为210 %,极限氧指数为38%,垂直燃烧达到V-0级别。     

改性Sb2O3协同十溴二苯乙烷阻燃LDPE/EVA的研究

采用熔融共混法制备了阻燃低密度聚乙烯/乙烯-醋酸乙烯共聚物(LDPE/EVA)复合材料,研究了表面有机化改性三氧化二锑(Sb2O3)与十溴二苯乙烷(DBDPE)在LDPE/EVA中的阻燃协效性,通过极限氧指数(LOI)、垂直燃烧等级(UL94)、力学性能和热稳定性等测试对复合材料进行研究。结果表明,DBDPE/Sb2O3复合阻燃剂对LDPE/EVA有良好的阻燃作用,经表面有机化改性的Sb2O3,较之未改性Sb2O3阻燃协效性增强,制品热稳定性提高,对力学性能影响较小。     

凹凸棒土增强EVA/NBR阻燃复合材料的性能研究

以氢氧化镁（MH）和红磷（RP）为阻燃剂（FR）制备了乙烯醋酸乙烯共聚物/丁腈橡胶(EVA/NBR)阻燃复合材料,并将凹凸棒土（AT）引入到EVA/NBR阻燃复合材料中,以提高其力学性能、耐油性、燃烧性能及热稳定性。结果表明,含有10 份（质量份,下同）AT的阻燃复合材料,其拉伸强度为10.4 MPa,断裂伸长率为627.1 %;浸油后拉伸强度变化率从-29.3 %降低到-13.2 %,断裂伸长率变化率从-25.2 %降低到-8.6 %,且质量增大变化率从10.7 %降低到3.4 %;极限氧指数达到了32.2 %,UL 94垂直燃烧从无等级提高到V 0级;700 ℃时残炭量从29.3 %提高到35.6 %;浸油前后断面观察发现,加入AT后阻燃复合材料的断面更加致密。     

低卤协同阻燃SBR燃烧性能和热失重行为的研究

以丁苯橡胶（SBR）为主体材料,利用十溴二苯乙烷（DBDPE）、三氧化二锑（Sb2O3）、膨胀阻燃剂（IFR）和氢氧化铝（Al（OH）3）/红磷（P）复配制备了阻燃SBR。利用氧指数仪（LOI）、垂直燃烧试验仪（UL-94）、锥形量热仪（CONE）和热重分析仪（TG）研究了阻燃SBR的燃烧性能和热失重行为。结果表明,加入40份DB-DPE/Sb2O3/IFR、DBDPE/Sb2O3/Al（OH）3/P和DBDPE/Sb2O3/IFR/Al（OH）3/P阻燃体系,使SBR的LOI分别达到23%,25%,27%,PHRR值分别下降到564,747,536kW/m2,DBDPE/Sb2O3/IFR/Al（OH）3/P阻燃体系阻燃效果最好,具有低卤高效的阻燃性能;热失重研究表明,空气气氛下,在500℃时,DBDPE/Sb2O3与Al（OH）3/P不会发生反应,独立阻燃;在800℃时,SBR/DBDPE/Sb2O3/IFR/Al（OH）3/P阻燃SBR残炭量最高,说明随着温度的升高,阻燃剂之间逐渐发生反应,协同阻燃,有效地促进成炭,从而提高了试样的阻燃性能。     

基于磷氮协同阻燃体系的抗静电PBT材料的性能研究

采用聚对苯二甲酸丁二醇酯（PBT）作为基体树脂、二乙基次磷酸铝（AlPi）和三聚氰胺次磷酸盐（MPP）以质量比2∶1的配比作为协效阻燃剂、炭黑（CB）作为抗静电填料,制备了阻燃抗静电PBT材料。通过极限氧指数、UL 94垂直燃烧实验、热重分析和扫描电子显微镜分别研究了PBT复合材料的燃烧性能、热稳定性、抗静电性能并测试了其体积电阻率。结果表明,复合材料的阻燃级别达到UL 94 V-0级,极限氧指数为31 %;CB的阈值为12份（质量份,下同）,CB加入量为20份时的体积电阻率达到104 Ω·cm;复配阻燃剂和CB对材料的热稳定性有一定程度的改善,复合材料燃烧后表面形成多孔连续的炭层,获得了优良的阻燃效果。     

Synthesis of a magnesium/aluminum/iron layered double hydroxide and its flammability characteristics in halogen‐free,flame‐retardant ethylene/vinyl acetate copolymer composites

Mg–Al–Fe ternary hydrotalcites were synthesized by a coprecipitation method and characterized with powder X‐ray diffraction, Fourier transform infrared spectroscopy, and thermogravimetric analysis. The flame‐retardant effects of Mg/Al–CO₃ layered double hydroxides (LDHs) and Mg/Al/Fe–CO₃ LDHs in an ethylene/vinyl acetate copolymer (EVA) were studied with the limited oxygen index (LOI), the UL‐94 test, and the cone calorimeter test (CCT), and the thermal degradation behavior of the composites was examined by thermogravimetric analysis. The results showed that the LOI values of the EVA/(Mg/Al/Fe–CO₃ LDH) composites were basically higher than those of the EVA/(Mg/Al–CO₃ LDH) composites at the same additive level. In the UL‐94 test, there was no rating for the EVA/(Mg/Al–CO₃ LDH) composite at the 50% additive level, and a dripping phenomenon occurred. However, the EVA/(Mg/Al/Fe–CO₃ LDH) composites at the same loading level of LDHs containing a suitable amount of Fe³⁺ ion reached the V‐0 rating, the dripping phenomenon disappearing. The CCTs indicated that the heat release rate (HRR) of the EVA composites with Mg/Al/Fe–CO₃ LDHs containing a suitable amount of Fe³⁺ decreased greatly in comparison with that of the composites with Mg/Al–CO₃ LDHs. The introduction of a given amount of Fe³⁺ ion into Mg/Al–CO₃ LDHs resulted in an increase in the LOI, a decrease in the HRR, and the achievement of the UL‐94 V‐0 rating. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

有机蒙脱土对EVA/IFR复合材料阻燃性能的影响

以聚磷酸铵（APP）和季戊四醇（PER）为膨胀型阻燃剂（IFR）制备了含有蒙脱土的无卤阻燃乙烯 醋酸乙烯共聚物（EVA）复合材料。通过极限氧指数、热失重分析、锥形量热分析等手段研究了有机蒙脱土(OMMT)的存在对EVA阻燃性能和热降解性能的影响,并通过扫描电子显微镜对复合材料残炭表面形貌进行了观察和分析。结果表明,加入有机蒙脱土可以促进复合材料成炭、改善炭层质量,从而起到了良好的隔热、抑烟作用;OMMT的最佳添加量为3份（质量份数,下同）,复合材料的极限氧指数可达到29.4 %,垂直燃烧可达V 0级。     

钼酸铵对EVA/NBR复合材料燃烧性能及热稳定性的影响

采用共混法在乙稀醋酸乙烯共聚物/丁腈橡胶（EVA/NBR）复合材料中加入钼酸铵（AHM）,通过烟密度测试、燃烧行为测试及热重分析研究了钼酸铵对复合体系的燃烧性能、抑烟性及热稳定性的影响。结果表明,添加1.0份（质量份,下同）AHM的复合材料的最大烟密度值降低到59.5 %,且烟密度等级仅为34.7,极限氧指数可达到33.3 %,UL 94垂直燃烧等级达到V-0级别,且燃烧时最大热释放速率从302 kW/m2降低到241 kW/m2;加入AHM后,复合材料的热稳定性提高;加入AHM后,烟密度实验后的残炭表面形貌更加致密。     

Influence of red phosphorus on the flame-retardant properties of ethylene vinyl acetate/layered double hydroxides composites

Mg?CAl?CFe ternary layered double hydroxides (LDHs) were synthesized based on Bayer red mud by a calcination?Crehydration method, and characterized using powder X-ray diffraction and thermogravimetric analysis techniques. The synergistic flame-retardant effects of red phosphorus (RP) in ethylene vinyl acetate (EVA)/LDHs composites were studied with the limiting oxygen index (LOI), the UL 94 test, the cone calorimeter test (CCT), and the smoke density test (SDT). And, the thermal degradation behavior of the composites was examined by thermogravimetry-Fourier transform infrared spectrometry (TG-FTIR) analysis. Results showed that the LOI values of the composites with RP were basically higher than those of the pure EVA sample and composites containing LDHs only. And the addition of a suitable amount of RP in EVA/LDHs/RP composites can apparently favor UL 94 test. In the UL 94 test there was a V-1 rating and dripping phenomena for the composites containing 50?% LDHs. However, the composites containing 47.5?% LDHs and 2.5?% red phosphorus did not drip. The CCT results indicated that the heat release rate (HRR) of the EVA/LDHs/RP composites with a suitable amount of RP decreased in comparison with that of the EVA/LDHs composites. The SDT showed that RP was helpful to smoke suppression. TG-FTIR data showed that the EVA/LDHs/RP composites show a higher thermal stability than the EVA/LDHs composites. A suitable amount of RP in EVA/LDHs/RP composites resulted in an increase in LOI values, a decrease in the HRR, the achievement of the UL 94 V-1 rating with no dripping phenomenon, a good smoke suppression character, and a high thermal stability.     

辐射改性电缆护套管的性能研究

采用低密度聚乙烯/乙烯-醋酸乙烯（PE-LD/EVA）为电缆料的主体基材,氢氧化镁［Mg(OH)2］为主阻燃剂,研究了乙烯-辛烯共聚物（POE）和有机蒙脱土（OMMT）对电缆料力学性能和阻燃性能的影响;并利用γ射线交联技术,探讨了辐射剂量对材料力学性能和阻燃性能的影响。结果表明,随着POE用量的增加,材料的拉伸强度和断裂伸长率增加,但硬度降低;OMMT的添加量为4份时,其与Mg(OH)2可以产生最佳的协同效应,改善了材料的力学性能和阻燃性能;当辐照剂量在90～100 kGy时,PE-LD/EVA/Mg(OH)2/OMMT＝50/50/60/4的共混体系的综合性能达到比较理想的水平,其极限氧指数超过32 ％,拉伸强度为11 MPa,断裂伸长率超过900 ％。     

Synergistic flame retardant effects of ammonium polyphosphate in ethylene‐vinyl acetate/layered double hydroxides composites

Mg–Al–Fe ternary layered double hydroxides (LDH) were synthesized based on bayer red mud by calcination‐rehydration method, and characterized using X‐ray diffraction and thermogravimetric analysis (TGA). The synergistic flame retardant effects of ammonium polyphosphate (APP) with LDH in ethylene‐vinyl acetate (EVA) composites were studied using limiting oxygen index (LOI), UL 94 test, cone calorimeter test (CCT), and smoke density test (SDT). The thermal degradation behavior of EVA/LDH/APP composites was examined by thermal gravimetric analysis‐fourier transform infrared spectrometry (TG‐FTIR). The results showed that LOI values decreased by incorporation of APP together with LDH; and, a suitable amount of APP in EVA/LDH composites can apparently improve UL 94 rating. The CCT results indicated that heat release rate (HRR) of the EVA/LDH/APP composites with APP decreased in comparison with that of the EVA/LDH composites. The SDT results showed that APP was helpful to suppress smoke. The TG‐FTIR data showed that the composites with APP had a higher thermal stability than the EVA/LDH composites at high temperature. POLYM. ENG. SCI., 54:766–776, 2014. © 2013 Society of Plastics Engineers     

Combustion characteristics and synergistic effects of red phosphorus masterbatch with expandable graphite in the flame retardant HDPE/EVA composites

In this work, the flammability behaviors and synergistic effects of red phosphorus masterbatch (RPM) with expandable graphite (EG) in flame‐retardant high‐density polyethylene/ethylene vinyl‐acetate copolymer (HDPE/EVA) composites have been investigated by limiting oxygen index (LOI), UL‐94 test, cone calorimeter test (CCT), thermogravimetric analysis (TGA), Fourier‐transform infrared (FTIR) and scanning electron microscopy (SEM). The data obtained from LOI, UL‐94 test and CCT showed that suitable amount of RPM had synergistic effects with EG in the HDPE/EVA/EG/RPM composites. The addition of RPM greatly increased the LOI values by 3.4%, obtained UL‐94 V‐0 rating, decreased the heat release rates and total heat release, and prolongated the ignition time when 6.7 phr RPM substituted for EG in the HDPE/EVA/EG/RPM composites. The data from TGA and FTIR spectra also indicated the synergistic effects of RPM with EG considerably enhanced the thermal degradation temperatures. The morphological observations after UL‐94, CCT, and SEM images presented positive evidences that the synergistic effects took place for RPM with EG, and the flame‐retardant mechanism has been changed in flame‐retardant HDPE/EVA/EG/RPM composites. The formation of stable and compact charred residues promoted by RPM acted as effective heat barriers and thermal insulations, which improved the flame‐retardant performances and prevented the underlying polymer materials from burning. POLYM. ENG. SCI., 55:2884–2892, 2015. © 2015 Society of Plastics Engineers