动态硫化NBR/PFPA热塑性弹性体热性能的研究

试验研究动态硫化NBR／石油发酵尼龙（PFPA）热塑性弹性体的热性能。结果表明，随着PFPA用量的增大，动态硫化NBR／PFPA热塑性弹性体的玻璃化温度升高，熔点降低，熔融焓减小，热稳定性提高；动态硫化NBR／PFPA热塑性弹性体的热降解过程分2个阶段进行，且2个阶段均为一级反应。     

氯化顺丁橡胶与CR，NBR或CPE并用胶性能的研究

考察氯化顺丁橡胶(CBR)用量对其与CR，NBR或CPE并用胶的物理性能、耐老化性能和阻燃性能的影响。结果表明，随CBR用量的增大，CBR／CR和CBR／NBR的拉伸强度和拉断伸长率均下降，CBR／CPE的这两项性能均提高；老化或浸油后，3种并用胶的拉伸性能均随CBR用量的增大而下降；随CBR用量的增大，CBR／NBR的阻燃性能改善，CBR／CR和CBR／CPE的阻燃性能下降。     

共混比对丁腈橡胶/氯醚橡胶性能的影响

研究了共混比时常规共混及动态硫化共混丁腈橡胶(NBR)／氯醚橡胶(ECO)的力学性能及加工流变性能的影响。结果表明,共混比对NBR／ECO胶料的力学性能及加工流变性能影响显著。NBR经动态硫化后,压缩永久变形及挤出胀大明显减小,拉伸强度提高,表现黏度随ECO用量的增大而减小。共混比对常规共混胶的表观黏度影响不大。动态硫化有利于改善NBR／ECO胶料的加工性能。     

炭黑填充型粉末NBR的制备与性能研究

采用高分子树脂包覆剂制备炭黑N330填充型粉末NBR[P（NBR／N330）3，并对其性能进行研究。结果表明，随着分散剂和包覆剂用量的增大，P（NBR／N330）粒子的粒径减小；当分散剂用量为10份、包覆剂用量为6份、炭黑N330用量为60份时，P（NBR／N330）硫化胶的综合物理性能优异，并接近块状NBR的水平。     

PVC/TPU/NBR三元共混物的制备及性能研究

对PVC／热塑性聚氨酯（TPU）／SR三元共混物的性能进行研究，重点讨论NBR品种、TPU／NBR并用比、PVC聚合度、增塑剂DOP和硫化剂DCP用量对PVC／TPU／NBR三元共混物性能的影响。结果表明。PVC／TPU／NBR-3604三元共混物的物理性能较优；PVC／TPU／NBR-3604三元共混物的拉断伸长率和拉断永久变形均随着PVC聚合度的增大基本呈上升趋势；随着增塑剂DOP用量的增大，共混物的邵尔A型硬度、拉伸强度、撕裂强度和拉断永久变形均基本呈下降趋势，拉断伸长率增大；随着硫化剂DCP用量的增大。共混物的拉伸强度和拉断伸长率变化不大，撕裂强度基本呈逐渐减小的趋势。不同PVC／TPU／SR三元共混物的扫描电子显微镜照片表明，NBR与PVC和TPU的相容性较好。     

不同用量白炭黑对NBR/BRR的动态力学性能和Payne effect效应的影响

本文利用扫描电镜SEM和橡胶加工分析仪(RPA-2000)设备,研究了不同白炭黑用量的NBR/BR并用胶的动态性能和微观形貌。结果表明：随着白炭黑用量的增大,白炭黑聚集体增多,白炭黑与橡胶基体间的相互作用增大,混炼胶的Payne效应增大。动态性能方面,随温度升高,NBR/BR混炼胶损耗因子先增大后减小;随白炭黑用量增大,NBR/BR混炼胶损耗因子在低温时增大,高温时减小;随温度升高, NBR/BR硫化胶储能模量G’变化不大,损耗因子减小。随白炭黑用量增大,NBR/BR硫化胶储能模量G’增大,损耗因子增大;随着温度的升高,NBR/BR硫化胶的损耗因子先增大后减小。     

复合硫化体系下NBR/EVM共混胶耐热空气及耐油性能研究

在复合硫化体系作用下,研究了NBR/EVM(EVM800HV和EVM500HV)共混比对硫化胶硫化特性、物理机械性能、热空气老化性能和热油老化性能的影响。结果表明,随EVM用量的增大,NBR/EVM硫化胶的交联密度逐渐减小,Ts1逐渐增大,胶料的操作安全性逐渐变好,T90逐渐增大;拉伸强度和300%定伸应力逐渐减小,且NBR/EVM500HV硫化胶减小更显著,硬度和100%定伸应力略微减小,NBR/EVM500HV硫化胶的扯断伸长率随EVM500HV用量增大逐渐增大,NBR/EVM800HV硫化胶的扯断伸长率随EVM800HV用量增大而基本保持不变。     

填充型NBR/EPDM导电复合材料的研究

研究了石墨/炭黑填充的NBR/EPDM导电复合材料力学性能、动态力学性能和压阻、温阻特性。结果表明,随NBR用量的减少,复合材料拉伸强度、撕裂强度和拉断伸长率均降低;与纯胶相比,填料在NBR/EPDM中分散性变差,复合材料Payne效应和损耗因子都增大。电阻率测试结果表明,NBR/EPDM并用胶电阻率明显低于纯胶;恒温下其电阻率随压力的增大先减小后增大;恒压下其电阻率随温度的升高而减小;NBR/EPDM并用比不同时,复合材料电阻率随压力、温度的变化趋势不尽相同。     

NR/BR/NBR并用胶的结构与性能

研究了NR／BR／NBR并用胶的结构与性能。透射电子显微镜分析显示，随着NBR用量的增大，炭黑的分散趋于均匀；NR／BR／NBR并用胶出现两个玻璃化温度，在O℃时的tanδ值增幅较大，而在65和80℃时的tanδ值变化不大；并用胶物理性能变化不大。通过调节NBR用量可获得抗湿滑性能较好、滚动阻力和生热小的胎面胶。     

炭黑N115填充胶料动态性能及生热特性研究

试验研究炭黑N115用量对SBR／BR胶料动态性能和生热特性的影响。结果表明，胶料tanδ随着温度的升高而减小；0℃左右的tanδ在炭黑用量40～70份范围内随炭黑用量的增大总体呈增大趋势，在70～90份范围内则呈减小趋势；炭黑用量为70份时胶料的湿抓着性最佳；60℃左右的tanδ随炭黑用量的增大总体呈增大趋势；胶料损耗模量和生热率随温度的升高而减小，随炭黑用量的增大而增大。     

耐油性PA6/NBR共混物的制备与性能研究

采用不同种类的丁腈橡胶(NBR)与聚酰胺6(PA6)熔融共混制备了聚酰胺6/丁腈橡胶混合物(PA6/NBR),考察了共混过程中转矩值的变化,并研究了不同腈基含量共混物的拉伸性能及耐溶剂性能。结果表明,随着橡胶相含量的增加,共混物的熔体黏度、体积溶胀率与质量溶胀率均显著提高,但拉伸强度下降。红外光谱分析表面NBR与PA6在高温高剪切作用下存在微化学反应,并且随腈基含量的增加,PA6/NBR共混物的平衡转矩值增大,拉伸强度明显提高,耐溶剂性下降。     

Effects of trans‐polyoctylene rubber on rheological and green tensile properties of natural rubber/acrylonitrile–butadiene rubber blends

The influence of trans‐polyoctylene rubber (TOR) on the flow property, die swell behaviour and green tensile property of NR (natural rubber)/NBR (acrylonitrile–butadiene rubber) blend compound was investigated as a function of TOR loading level. The pure TOR, NR and NBR compounds were also investigated for comparison with the blend compounds. The shear viscosity of TOR strongly depended on the temperature as well as shear rate. The viscosity of the NR/NBR blend compound was even lower than that of the constituent components at relatively lower shear rates, and the viscosity difference became smaller as the shear rate was increased. The viscosity of the NR/NBR blend compounds was strongly affected by the addition of TOR but the effect became negligible with increasing the shear rate. Both the die‐swell ratio and the surface topology of extrudates were also affected by TOR addition; the dependence on shear rate was much stronger for higher TOR level. The NR/NBR blend compound showed much higher green tensile strength and elongation at break than those of the constituent components. Both the green tensile modulus and strength of the NR/NBR blend compound were greatly enhanced, while the elongation at break was reduced with the addition of TOR. © 2002 Society of Chemical Industry     

Effect of rubber content on morphology and thermal and rheological behaviors of acrylonitrile-butadiene rubber/poly(ethylene-co-vinyl acetate)/organoclay nanocomposites

Thermoplastic elastomer nanocomposites based on acrylonitrile butadiene rubber (NBR) and poly(ethylene-co-vinyl acetate) (EVA) with different weight ratios (20, 40 and 60 wt% of NBR) and 5 wt% of organocaly (OC) were prepared in an internal mixer. The results obtained from X-ray diffraction and transmission electron microscopy (TEM) micrographs showed that due to the OC–EVA interaction, nearly all of the clay platelets were exfoliated. Scanning electron microscope (SEM) was used to investigate the particle size and phase morphology. SEM images for the unfilled blends revealed a two-phase structure in which the NBR domains were dispersed into the EVA phase. However, for the blend containing 60 wt.% of NBR, a co-continuous morphology was exhibited. The addition of OC decreased the NBR domain size significantly in which NBR remained as a dispersed phase even for the blend having the highest amount of NBR studied. Young's modulus and yield stress increased, but elongation at break and stress at break decreased for the nanocomposites in comparison with that of the unfilled materials. Thermal studies indicated that although OC decreased the degree of crystallinity and crystallization temperature of EVA slightly, it showed no effect on EVA melting temperature in comparison with that of the unfilled samples. It was also found that the nanocomposites behaved as shear thinning fluids over the entire range of angular frequency and the values of storage modulus and stress relaxation modulus of the nanocomposite containing 20 wt% of NBR was even higher than that of the NBR alone.     

丁腈橡胶/聚酰胺热塑性硫化胶的制备

用橡塑预混法、二步法和母炼胶法制备了丁腈橡胶／聚酰胺热塑性硫化胶(NBR／PATPV),研究了3种工艺对NBR／PATPV相态结构、流变性能、物理机械性能和耐溶剂性能的影响。结果表明,NBR与PA在高温、高剪切作用下,两相界面之间可发生微化学反应,但并不影响动态硫化时两相之间的相态反转过程。用橡塑预混法可制得分散相粒径小且分布均匀的TPV,该TPV的100％定伸应力大,压缩永久变形小,耐溶剂性能不佳,表观黏度略大,但挤出物外观光滑。     

Preparation and mechanical properties of nitrile butadiene rubber/silicate nanocomposites

Elastomer nanocomposites consisting of nitrile butadiene rubber (NBR) latex and layered silicates are prepared by a modified latex shear blending process aided with ball milling. The mode of dispersion of layered silicates in NBR is partially exfoliated and intercalated when the concentration of layered silicates is below 7.5 wt%, as evidenced by transmission electron microscopy and X-ray diffraction results. The tensile and tear mechanical properties are much higher than that of neat NBR. Specifically, the tensile and tear mechanical properties of the NBR/layered silicates increase by 200 and 60%, respectively. The decomposition temperature of the nanocomposites increases slightly.     

沥青基短切碳纤维/导电炭黑/丁腈橡胶复合材料的结构与性能研究

研究导电炭黑VXC72及沥青基短切碳纤维(CF)用量对丁腈橡胶(NBR)物理性能、导热及导电性能的影响。结果表明,随着导电炭黑VXC72用量的增大,NBR胶料和CF/NBR复合材料的拉伸强度、撕裂强度、定伸应力和热导率逐渐增大,体积电阻率逐渐降低,而且CF/NBR硫化胶的50%、100%定伸应力和热导率比NBR硫化胶有不同程度提高。当导电炭黑VXC72用量相同时,随着CF用量的增大,复合材料的拉伸强度、撕裂强度和拉断伸长率先减小后增大,热导率基本呈线性增加,体积电阻率明显降低。     

HDPE／NBR共混物流变性能研究

通过熔融共混法制备了HDPE／NBR共混物,用毛细管流变仪研究了其流变特性,此共混物属于假塑性流体,表观粘度随剪切速率和温度的升高而降低,随NBR和增容剂含量的降低而降低。     

Melt Rheology and Morphology of Nitrile Rubber and Ethylene-Vinyl Acetate Copolymer Blends

The melt Theological behavior of nitrile rubber (NBR)/ethylene-vinyl acetate (EVA) copolymer blends was studied with special reference to the effect of the blend ratio, cross-linking systems, and shear rate using a capillary rheometer. At a given shear stress at 90°C, the viscosities of the blends vary slightly with composition. The effect of cross-linking systems [viz., sulfur (S), peroxide (DCP) and mixed (S+DCP) systems] on the viscosity of NBR/EVA blends is negligible. The melt viscosity of the blends decreases with increasing shear rate, showing pseudoplastic behavior. The flow behavior index values also support the pseudoplastic nature of these blends. Various theoretical models were used to predict the melt viscosity of the blends. Parameters such as die swell, principal normal stress difference, recoverable shear strain, and shear modulus were calculated to characterize the melt elasticity of these blends. The melt elasticity of the system was increased by the addition of NBR to EVA. The extrudate deformation at different shear rates was also studied. It was observed that as the shear rate increases, the extrudate surface exhibits a higher degree of deformation. The morphology of the extrudates of the blends at different shear rates has been examined by a scanning electron microscope. The morphology was found to be dependent on the blend ratio and shear rate.