MPU/NBR与MPU/EPDM共硫化匹配性的比较

本文分别对MPU/NBR共混胶和MPU/EPDM共混胶进行了不同并用比的实验研究,分别将二者在硫化特性曲线、拉断强度变化、应力-应变关系、热氧老化性能变化以及动态生热性能变化规律进行对比,结果发现,MPU/EPDM共混胶的硫化匹配程度明显好于MPU/NBR共混胶。在MPU中加入NBR会使得MPU相的硫化受到抑制,硫化程度过低,这是由于二者硫化特性不匹配所造成。与之对比的MPU与EPDM硫化特性相近,MPU/EPDM共混胶两相影响较小。     

不同硫化工艺对CR/NBR共混胶热油老化前后力学性能及胶管扣压性能的影响

本文主要研究了不同硫化工艺对CR/NBR共混胶热油老化前后力学性能的影响,采用预硫化的方法将CR部分预先硫化一定时间后,然后与NBR共混,研究预硫化对共混胶耐热油老化前后性能的影响。硫化特性实验表明预硫化工艺会降低最大转矩及转矩差值,t_(10)缩短。物理机械性能实验结果表明:预硫化工艺使得共混胶热油老化后拉断强度增大,扯断伸长率增大,老化前后性能保持率提高,综合性能改善。仿真计算结果表明预硫化工艺使得静刚度、应力集中单元处应变能密度及相同节点处Mises应力减小。     

硫化特性匹配对混炼型聚氨酯橡胶/丁腈橡胶共混胶性能的影响

考察了混炼型聚氨酯橡胶（MPU）和丁腈橡胶（NBR）硫化特性匹配对MPU/NBR共混胶性能的影响。结果表明,对MPU进行130 ℃热处理后再进行混炼,可缩短硫化诱导期,使其硫化特性与NBR接近,可减小硫化体系的相间偏析,从而增强MPU/NBR共混胶的硫化程度,提高共混胶的物理机械性能。当热处理时间为8 min时,MPU/NBR共混胶的拉伸强度提高37%,耐热油老化性能得到明显改善。     

ACM预硫化时间对NBR/ACM共混胶性能的影响

研究了在丁腈橡胶(NBR)与丙烯酸酯橡胶(ACM)共混胶中ACM预硫化时间对共混胶性能的影响。结果表明NBR硫化速度远快于ACM,ACM预硫化工艺能有效提高其硫化程度以及与NBR相的硫化同步性。随着ACM预硫化时间的增加,共混硫化胶拉断强度、扯断伸长率均先增大后减小,100%定伸强度逐渐增大,共混硫化胶耐热空气老化性能先提高后降低,耐油性能逐渐提升。随着ACM预硫化时间的增加,共混胶中ACM相交联密度逐渐增大;热空气老化后,共混胶中ACM相交联密度变化率逐渐缩小;ACM预硫化工艺对共混胶中NBR相交联密度几乎无影响。ACM预硫化工艺可以改善其在NBR中的分散效果。     

CZ/TMTD并用量对NBR/ACM共混胶性能的影响

研究了在NBR/ACM共混胶中,使用半有效硫磺硫化体系条件下,促进剂CZ/TMTD并用量对NBR/ACM共混胶性能的影响。测试了不同CZ/TMTD并用量下NBR/ACM共混胶的硫化特性、力学性能及耐老化性能。结果表明,随着TMTD用量增大、CZ用量的减小,NBR/ACM共混胶硫化程度逐渐增大、硫化速度加快,但焦烧时间迅速减小,加工安全性变差;共混硫化胶扯断伸长率逐渐降低,硬度、拉断强度及100%定伸强度均先升高后降低;共混硫化胶耐热空气、热油老化性能均升高。     

NBR/BR共混胶耐油及耐低温性能研究

研究了NBR并用BR后,共混硫化胶的硫化特性、力学性能、耐热油老化性能和低温性能。结果表明,NBR并用20份BR后,共混胶硫化程度有所降低,硫化速率升高;拉断强度、扯断伸长率及100%定伸应力略有降低,硬度基本不变;在高温条件下测试,力学性能明显降低,且仍低于NBR硫化胶;耐热油老化性能基本不变,耐低温性能明显提升。     

CSM改性NBR共混胶性能的研究

主要研究了硫载体硫化体系下的NBR/CSM共混胶力学性能、耐热老化性能和耐油性能。结果表明,随着CSM用量的增大,共混胶拉伸强度和硬度均增大,拉断伸长率和撕裂强度均减小,耐油性变差;随着CSM用量的增大,共混胶失重峰温度降低,失重率变大,高温稳定性变差;150℃×24h热空气老化条件下的共混胶拉伸强度保持率增大,耐热老化性能变好;随着CSM用量的增大,共混胶耐臭氧老化性能变好。     

不同共混比NBR/CR共混胶的性能研究

研究了普通硫黄硫化体系下不同共混比的NBR/CR共混胶在热空气以及热油老化(100 ℃,72 h)前后物理机械性能的变化规律。结果表明,老化前随着CR用量的增多,NBR/CR共混胶的M_H-M_L随之增大,硫化程度变大,硬度变大,拉伸强度略微上升;热空气老化后,NBR/CR共混胶随CR用量的增多,拉伸强度略微上升,扯断伸长率下降,但其扯断伸长率变化率以及100%定伸应力变化率较NBR硫化胶的变化率小,即加入CR后NBR/CR共混胶耐热空气性能得到改善;NBR/CR共混胶经热油老化后,硬度下降,拉伸强度略微下降。     

相容剂对混炼型聚氨酯橡胶/丁腈橡胶共混胶性能的影响

以丙烯酸酯橡胶（ACM）和乙烯丙烯酸酯橡胶（AEM）作为相容剂,研究其对混炼型聚氨酯橡胶（MPU）/丁腈橡胶（NBR）共混胶性能的影响。结果表明：在MPU/NBR共混胶中加入相容剂ACM和AEM,可以促进MPU与NBR的共硫化,使二者的硫化特性更加匹配,提高了共混胶的相容性、物理性能、耐热性能和耐热氧老化性能,相容剂AEM对共混胶的性能改善效果优于相容剂ACM;当相容剂AEM用量为20份时,共混胶的两相已完全相容。     

硫黄用量对NBR/CM并用胶性能的影响

研究在硫黄/过氧化物硫化体系下硫黄用量对NBR/氯化聚乙烯橡胶(CM)性能的影响。结果表明,随着硫黄用量的增大,NBR/CM并用胶的交联密度增大,硫化速率先增大后减小;硫化胶的100%定伸应力呈下降趋势,拉伸强度、拉断伸长率、浸油前后的质量变化率和体积变化率均先增大后减小,撕裂强度和压缩永久变形呈增大趋势,耐磨性能提高,耐热空气老化性能下降;当硫黄用量为0.8份时,NBR/CM并用胶的综合性能较好。     

动态硫化丁腈橡胶/尼龙6热塑性弹性体的制备及性能

采用动态硫化法制备了丁腈橡胶/尼龙6热塑性弹性体(NBR/PA 6 TPV),考察了硫化体系、羧基丁腈橡胶(XNBR)以及增塑剂高密度氧化聚乙烯蜡(AC-316 A)和正丁基苯磺酰胺(BBSA)对TPV硫化特性、力学性能和微观形貌的影响。结果表明,以促进剂HVA-2/促进剂DM为硫化体系,动态硫化过程体系黏度的变化比以酚醛树脂/SnCl2为硫化体系时更平稳;但用后者制备TPV,其撕裂强度和扯断伸长率等力学性能更优,PA 6的结晶度更低。XNBR能对NBR和PA 6起到增容作用,当XNBR与NBR的质量比为10/90时,TPV的力学性能最好,NBR在PA 6中分散得最均匀。AC-316 A和BBSA都能对TPV起到增塑作用,随其用量的增加,体系黏度降低。     

三元尼龙对丁腈橡胶力学性能及耐介质性的影响

采用三元尼龙改性丁腈橡胶（NBR）,研究尼龙用量对NBR混炼胶加工工艺性能和硫化胶力学性能、耐老化性能、耐介质性能的影响。结果表明：尼龙的添加有效地提高了NBR硫化胶的强度以及耐磨性能,老化性能也得到改善,拉伸强度基本上是随着尼龙用量的增加而增大,其中尼龙用量为5phr时,硫化胶的综合物理机械性能较好;耐油系数亦随阻尼用量的增加而逐渐增大,尼龙的加入提高了硫化胶的耐热油性;耐混合溶剂后的体积变化率随着尼龙用量的增加而逐渐降低。     

Physical properties of polyamide 6/H‐NBR blends and the effects of dynamic vulcanization on them

Polyamide 6 (PA 6) and hydrogenated nitrile rubber (H‐NBR) were blended with various blend ratios in a brabender plasticoder at 240°C/100 rpm. The processing characteristics with a mixing torque of the blends were investigated. The effect of the blend ratio on physical properties such as tensile strength, Young's modulus, elongation at break, permanent set, hardness, and swelling behavior of blends was analyzed. Most mechanical properties were found to decrease with an addition of H‐NBR. The morphology of the blends was observed, and the results show a two phase system where the component with high proportions exists as a continuous phase. A cocontinuous phase was observed in blend ratios of 50/50 and 40/60. Dynamic mechanical properties were observed to study a viscoelastic property of the blends. In addition, the effect of dynamic vulcanization with peroxide on physical properties was studied, and the influence of peroxide on PA 6 was also examined. It was found that the peroxide can have an effect on PA 6 as well as act as a crosslinker to H‐NBR. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

软质NBR_PVC混炼胶性能及流变行为的研究

以腈基含量较少的 NBR 80份(质量份)和 PVC 20份共混,并配以 50份自制的海绵状软化剂R-1及其他配合剂时,胶料辊筒行为良好,所得软质NBR/PVC硫化胶具有硬度低、耐磨、耐油、耐老化、弹性好、拉伸强度高等优良性能,可采用挤出成型工艺制造优质印刷胶辊。     

Dynamically vulcanized nitrile rubber/polypropylene thermoplastic elastomers

A new compatibilized method was used to prepare thermoplastic elastomer (TPE) of nitrile rubber (NBR) and polypropylene (PP) with excellent mechanical properties by dynamic vulcanization. Glycidyl methacrylate (GMA) grafted PP/amino‐compound was used as a compatibilizer. The effects of the curing systems, compatibilizer, PP type, and reprocessing on the mechanical properties of NBR/PP thermoplastic elastomers were investigated in detail. Experimental results showed that the addition of amino‐compound in the compatibilzer can significantly increase the mechanical properties of the NBR/PP thermoplastic elastomer. Compared with other amino‐compounds, diethylenetriamine (DETA) has the best effect. PP with higher molecular weight is more suitable for preparing NBR/PP thermoplastic elastomer with high tensile strength and high elongation at break. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2862–2866, 2002     

Toughening of poly(L‐lactide) by melt blending with rubbers

Poly(L ‐lactide) (PLA) was melt‐blended with four rubber components—ethylene–propylene copolymer, ethylene–acrylic rubber, acrylonitrile–butadiene rubber (NBR), and isoprene rubber (IR)—in an effort to toughen PLA. All the blend samples exhibited distinct phase separation. Amorphous PLA constituted a topologically continuous matrix in which the rubber particles were dispersed. According to Izod impact testing, toughening was achieved only when PLA was blended with NBR, which showed the smallest particle size in its blend samples. In agreement with the morphological analysis, the value of the interfacial tension between the PLA phase and the NBR phase was the lowest, and this suggested that rubber with a high polarity was more suitable for toughening PLA. Under the tensile stress conditions for NBR and IR blend samples, these rubbers displayed no crosslinking and showed a high ability to induce plastic deformation before the break as well as high elongation properties; this suggested that the intrinsic mobility of the rubber was important for the dissipation of the breaking energy. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

A study on the compatibility and physical properties of chlorinated polyethylene rubber/nitrile rubber blends

The miscibility and some physicomechanical characteristics of chlorinated polyethylene rubber (CPE) and nitrile rubber (NBR) blends have been investigated. Calculation of the heat of mixing, differential scanning calorimetry, and scanning electron microscopy analysis showed that CPE was miscible with NBR in all proportions. The cure and scorch times decreased with the increase in NBR content, whereas the maximum torque increased. The tensile strength, 100% modulus, elongation at break, tear strength, and compression set decreased with increasing of NBR content. After aging, hardness and tensile strength increased, and there was no drastic change in elongation at break on aging. The thermal aging resistance and the abrasion resistance of NBR are improved after blending with CPE, but the oil resistance decreased. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

聚醚型混炼型聚氨酯与丁腈橡胶的并用研究

研究聚醚型混炼型聚氨酯(MPU)/丁腈橡胶(NBR)并用比对MPU/NBR并用胶性能的影响。结果表明:随着NBR用量的增大,胶料的M_H增大,t_(90)延长,硫化速率下降;硫化胶的交联密度增大,压缩永久变形减小,热稳定性和耐低温性能提高,耐臭氧老化性能下降,耐油性能变化不大。     

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。