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。     

EVA阻燃材料的制备与性能研究

通过极限氧指数、垂直燃烧、烟密度、锥形量热、扫描电子显微镜等表征方法,研究了不同用量自制哌嗪类膨胀阻燃剂（IFR）对乙烯醋酸乙烯共聚物（EVA）的阻燃作用。结果表明,添加30 %（质量分数,下同）IFR的EVA材料极限氧指数能达到37 %,UL 94垂直燃烧达到V-0级,有焰、无焰烟密度均很低,热释放速率峰值降至156 kW/m2,仅仅只有纯EVA的21.8 %,燃烧后形成了致密的膨胀炭层;该阻燃材料具有很低的吸湿率,力学性能保持较好,且能满足RoHS环保要求。     

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。     

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。     

无机填料填充PE-LD/EVA合金的导热及阻燃性能

采用氧化铝（Al2O3）为导热填料、氢氧化镁［Mg(OH)2］为阻燃填料,以低密度聚乙烯（PE-LD）和乙烯醋酸乙烯共聚物（EVA）为基体树脂制备导热阻燃复合材料。通过导热性能测试、燃烧行为表征（极限氧指数和垂直燃烧测试）以及热重分析研究了PE LD/EVA/Al2O3/Mg(OH)2复合材料的导热性能、阻燃性能及热稳定性。结果表明,含有50份Al2O3及50份Mg(OH)2的复合材料,在PE-LD/EVA质量比为1/1时,热导率可达到1.21 W/m·K;材料的阻燃性能及热稳定性都随 EVA 含量的增加而增大,极限氧指数从27.0 % 提高到31.5 %,UL 94 垂直燃烧从无等级提高到V-0级,残炭率从46.5 %提高到57.7 %。     

氢氧化铝/氢氧化镁复配提高乙烯-醋酸乙烯共聚物阻燃性能

研究了不同质量比的氢氧化铝(ATH)和氢氧化镁(MH)对乙烯-醋酸乙烯共聚物(EVA)燃烧性能的影响,通过极限氧指数测试、垂直燃烧测试、热失重分析和锥形量热测试研究了EVA/ATH/MH复合材料的阻燃性能和热稳定性。结果表明,固定ATH和MH的添加量为60%(质量分数,下同),ATH/MH=2/1(质量比,下同)时,EVA/ATH/MH复合材料的阻燃性能最好,极限氧指数从18.3%提高到34.3%,达到UL 94V-2级别,热释放速率和热释放总量均有明显下降。     

高弹性发泡聚丙烯的制备及性能表征

采用低密度、大比表面积的纳米Si O2为成核剂,乙烯-醋酸乙烯共聚物/丁腈橡胶(EVA/NBR)为增韧体,通过模压交联发泡制备了高弹性的聚丙烯(PP)发泡材料。研究了EVA、NBR添加量对PP发泡工艺与性能的影响。通过力学性能测试及形貌分析,考察了制备高弹性发泡PP的最佳工艺条件。实验结果表明,当EVA、NBR含量均为12.5%时,发泡PP综合性能最佳,拉伸强度为25 MPa,断裂伸长率为6.8%,冲击强度达到10.9 k J/m2,维卡软化温度为146.8℃。     

热重-质谱联用对膨胀型阻燃剂阻燃EVA的机理研究

采用极限氧指数仪和拉伸仪研究了膨胀阻燃剂阻燃乙烯醋酸乙烯共聚物（EVA）体系（APP/PER/MCA/ EVA）的阻燃及力学性能,并采用热重-质谱联用仪对该体系在空气中的热氧化降解进行了分析。结果表明,在APP/PER/MCA的配比为8/4/3、总添加量为40 % 时,阻燃EVA样品的阻燃和力学性能最好,其极限氧指数和拉伸强度分别为26 % 和6.62 MPa;与纯EVA相比,膨胀阻燃剂阻燃EVA的起始分解温度和失重率分别降低100 ℃和10 %,吸热量明显降低;阻燃EVA的热氧化降解过程中,H2O、CO2等小分子产物发生明显变化,且阻燃后苯环类化合物明显减少。     

交联无卤阻燃LLDPE/EVA电缆料的研制

以LLDPE（线性低密度聚乙烯）、EVA（乙烯醋酸乙烯共聚物）为基体树脂，ATH（氢氧化铝）、MH（氢氧化镁）为主阻燃剂，有机硅为阻燃增效剂，EVA-g-MAH（马来酸酐接枝乙烯醋酸乙烯共聚物）为高分子相容剂，DCP（邻苯二甲酸二壬酯）为交联剂制备了交联无卤阻燃LLDPE／EVA电缆料。研究结果表明，在燃烧时有机硅能促进玻璃态无机炭化层隔氧膜的形成，有效地提高共混物的氧指数。以EVA-g-MAH作为共混体系的相容剂能够改善交联无卤阻燃LLDPE／EVA电缆料的加工性能、力学性能和阻燃性能。     

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。     

纳米氢氧化铝填充LDPE/EVA的力学和阻燃性能

对纳米氢氧化铝（CG-ATH）在低密度聚乙烯/乙烯-醋酸乙烯酯共聚物体系中(low density polyethylene /ethylene vinyl acetate copolymer,简称LDPE/EVA),填充量对力学性质和阻燃性质的影响进行了研究.通过力学性能测试和SEM分析表明,随着CG-ATH填充量的增加,树脂体系的断裂伸长率急剧下降,而其拉伸强度则呈先下降后上升的趋势,当CG-ATH的填充量为60%时,其拉伸强度达12.5 MPa.通过燃烧性能测试、TG和DSC分析表明,CG-ATH的添加能够提高树脂体系的分解温度,增加结炭率,显著提高极限氧指数.通过综合分析,得到填充量为60%时,能够达到树脂体系力学性能与燃烧性能的最佳状态.     

用埃洛石负载氨基磺酸胍制备阻燃丁腈橡胶

以天然埃洛石纳米管（HNTs）作为载体,通过在其管内负载阻燃剂氨基磺酸胍（GAS）得到功能填料HNTs-GAS,以制备低烟无卤阻燃丁腈橡胶（NBR）。采用热重分析计算得到HNTs与GAS的投料质量比为1/3时可达到质量分数6%的最佳负载率。添加122.3份（质量,下同）HNTs-GAS和5.7份GAS的阻燃NBR复合材料的极限氧指数为28.3%,垂直燃烧达到V-1等级,烟密度为105,具有较好的阻燃性。HNTs-GAS的加入能有效提高NBR的力学性能,与添加相同用量HNTs和GAS的NBR相比,添加HNTs-GAS后NBR复合材料的拉伸强度、撕裂强度和扯断伸长率分别提高了47.5%、36.8%和67.1%。     

Properties of poly(butylene terephthalate)/functionalized polyolefin blends

The object of this study was to investigate the physical properties and morphology of melt-mixed blends containing poly(butylene terephthalate) (PBT) with several functionalized polyolefins such as ethylene/vinyl acetate copolymer (EVA), EVA-g-maleic anhydride (EVA-g-MAH), EVA-g-ACID, EVA-g-ACID/ACRYLATE, ethylene methacrylate-g-MAH (EMA-g-MAH), ethylene/ethyl acrylate copolymer (EEA) and an ethylene ionomer. Special focus was made on PBT/EVA-g-MAH and PBT/EMA-g-MAH blends compared with PBT/EVA and PBT/EMA blends. Blends were prepared in a counter-rotating twin-screw extruder. Mechanical and thermal properties, glass transition temperature and morphology were examined using a tensile testing machine, differential scanning calorimeter (DSC), dynamic mechanical analysis and Scanning Electron Microscope (SEM). PBT/EVA-g-MAH and PBT/EMA-g-MAH blends exhibited better impact strength than PBT/EVA and PBT/EMA blends because of the larger interfacial adhesion of EVA-g-MAH and EMA-g-MAH with PBT than EVA and EMA.     

Mechanical and tribological performance of acrylonitrile-butadiene rubber/carbon black/cryptocrystalline graphite composites

In this study, cryptocrystalline graphite (CG) was investigated as a novel functional filler for acrylonitrile-butadiene rubber (NBR)/carbon black (CB) composites. NBR/CB/CG composites are characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) as well as differential scanning calorimetry (DSC). The results showed that NBR/CB/CG-10 increased by 18.2%, 11.0%, and 10.0% in tensile strength, 300% tensile modulus and tear strength, respectively compared with NBR/CB. Uniform filler dispersion and stronger interfacial interaction contributed to enhancing the mechanical property of NBR/CB/CG composites. It was revealed that the small particle size, rough surface, and defective structure of CG facilitated its exfoliation and intercalation. In addition, the tribological performance of NBR/CB/CG composites was tested on a ring-on-block wear tester under dry sliding conditions. The friction coefficient and specific wear rate of NBR/CB/CG-5 reduced by 50.3% and 51.4%, respectively through the formation of fine lubrication and transfer films. CG enhanced the thermal stability, mechanical, and tribological performance of NBR composites simultaneously and the results of this work proved that CG would be a cost-effective and resource-available functional filler especially suitable for rubber seal application.     

Properties and characterization of ([Mengkuang leaf fiber]‐filled ethylene vinyl acetate)/(natural rubber) blend: Effects of blending sequences and mengkuang leaf fiber loading

(Ethylene vinyl acetate [EVA])/(natural rubber [NR])/(Mengkuang leaf fiber) (MLF) thermoplastic elastomer composites were prepared by using three different blending sequences in an internal mixer. The blending sequences studied were (i) B1: NR was added followed by MLF into the molten EVA; (ii) B2: MLF was added followed by NR into the molten EVA; (iii) B3: MLF was added followed by EVA into the molten NR. The effect of different blending sequences and fiber loadings from 10 to 40 parts by weight per hundred parts of resin on the torque development, tensile properties, thermal degradation, and morphology of EVA/NR/MLF composites was studied. Of the blending sequences investigated, the B1 system is considered the best method for the preparation of EVA/NR/MLF composites. The B1 system produces composites with lower stabilization torque, higher tensile strength, and better thermal stability compared with other systems. At 40 parts by weight per hundred parts of resin of MLF loading, the tensile strength of the composite prepared by using the B1 system was 15% higher than that of B2 system composites, and 8% higher than that of the B3 system. Scanning electron micrographs of the tensile fracture surfaces indicated this system also had good fiber dispersion in the EVA/NR matrix. An increase in MLF loading resulted in an increase of the values of the stabilization torque and the Young's modulus, but a decrease in values of the tensile strength, the elongation at break, and the thermal stability of the composites. Scanning electron microscopy revealed increased fiber pullout in the composites as the loading increased. J. VINYL ADDIT. TECHNOL., 24:109–115, 2018. © 2016 Society of Plastics Engineers     

基于乙烯-乙酸乙烯共聚物/丁腈橡胶热塑性硫化橡胶超亲水材料的制备与性能

采用动态硫化法制备了基于乙烯–乙酸乙烯酯共聚物/丁腈橡胶的热塑性硫化橡胶（EVA/NBR TPV）,以不同型号金相砂纸为模板,通过模压法在其表面构建具有微纳米结构的表面,研究了橡塑质量比对EVA/NBR TPV粗糙表面超亲水行为的影响及EVA/NBR TPV超亲水表面的微观结构和超亲水性能,并初步探讨了EVA/NBR TPV表面的亲水机制。结果表明,当EVA/NBR TPV的橡塑质量比为20/80时,采用模板法且以耐水砂纸为模板制得的EVA/NBR TPV表面亲水性较好。其中,当橡塑质量比为20/80时,以NO 1000砂纸为模板,模压温度为165 ℃,经过预热10 min、热压3 min、冷压5 min后制得的EVA/NER TPV薄膜表面的亲水性最佳。