反应型增塑剂LIR对NR/BR并用胶性能的影响

以液体聚异戊二烯橡胶（LIR）为反应型增塑剂,研究LIR对NR/BR混炼胶性能、硫化胶物理性能和耐热空气老化性能的影响,并与添加芳烃油的NR/BR并用胶进行对比.结果表明,LIR对NR/BR混炼胶有增塑作用,但增塑效果不如芳烃油;添加LIR的NR/BR硫化胶的物理性能总体上优于相应的芳烃油硫化胶,耐热空气老化性能也较好;LIR在硫化过程中可与NR和BR发生共交联.     

LIR对NR/BR混炼胶加工性能的影响

采用RPA2000橡胶加工分析仪研究液体聚异戊二烯（LIR）、芳烃油和LIR/芳烃油并用体系对NR/BR混炼胶加工性能的影响.结果表明,LIR和LIR/芳烃油并用体系均能有效改善NR/BR混炼胶的加工性能,且后者的增塑效果较LIR或芳烃油单用时更为显著,其对应的混炼胶粘度较小,工艺能耗和成本较低;LIR/芳烃油并用体系对应的NR/BR硫化胶性能良好,炭黑在其中的分散性也较好.     

不同增塑剂对喷蜡天然橡胶/顺丁橡胶自润滑性能的影响

研究了增塑剂种类如芳烃油、环烷油、邻苯二甲酸二辛酯(DOP)、石蜡油、三甘醇二异辛酸酯(3G8)、古马隆等对以油酸酰胺为润滑剂的自润滑喷蜡天然橡胶(NR)/顺丁橡胶(BR)共混胶硫化特性、力学性能、耐屈挠疲劳性能、摩擦系数、Payne效应、损耗因子(tan δ)的影响,对比分析了几种增塑剂应用于喷蜡NR/BR共混胶的自润滑效果。结果表明,加入3G8的NR/BR共混胶焦烧时间(t_(10))和正硫化时间(t_(90))较短,抗拉强度较大,耐屈挠疲劳性好,动摩擦系数和静摩擦系数最小,自润滑效果最好。另外,研究发现几种增塑剂对NR/BR胶料的炭黑分散效果影响较小,Payne效应区别不大,储能模量(G′)-应变曲线变化一致,NR/BR硫化胶的硬度、耐老化性能相差不大。     

低滞后炭黑DZ13对胎面胶物理性能及疲劳破坏行为的影响

采用以天然橡胶(NR)、NR/顺丁橡胶(BR)和NR/BR/溶聚丁苯橡胶(SSBR)为基体的轮胎胎面胶配方,研究低滞后炭黑DZ13对3种硫化胶物理性能和疲劳破坏行为的影响。结果表明:低滞后炭黑DZ13部分替代炭黑N234后,NR,NR/BR和NR/BR/SSBR硫化胶的物理性能变化规律相似,即定伸应力略有增大、拉断伸长率和撕裂强度减小;耐磨性能、耐压缩疲劳性能和耐割口增长性能的变化依赖于基体橡胶;其中NR/BR硫化胶的屈挠疲劳次数提高,但疲劳破坏界面的微观形貌更加粗糙。     

NR/BR并用质量比对胎侧胶臭氧老化和屈挠疲劳性能的影响

研究了轮胎胎侧胶中天然橡胶(NR)和顺丁橡胶(BR)比例对胎侧胶耐臭氧老化和屈挠疲劳性能的影响。结果表明,由于NR的自补强性,随着共混胶中BR比例增加,胶料的拉伸强度、撕裂强度、定伸应力降低,但回弹性增加。由于BR的柔顺性及防护蜡在NR中相对高的溶解度,防护蜡在BR含量高的胎侧胶中的迁移速度快,迁移量高。胎侧胶的耐臭氧老化性和动态屈挠疲劳性能均取决于硫化胶的强度和防护蜡的迁移速度和迁移量。纯NR和纯BR胶料的耐臭氧老化性能和耐屈挠性能均不理想,NR/BR(50/50～40/60)共混胶由于强度和蜡的迁移量间的平衡而具有更好的耐臭氧老化和耐屈挠疲劳性能。     

生胶体系对胎侧支撑胶耐屈挠性能的影响

天然橡胶(NR)和顺丁橡胶(BR)并用用于胎侧支撑胶中,研究生胶体系对胎侧支撑胶耐屈挠性能的影响。结果表明:随着NR/BR并用胶中NR用量的增大,胶料的炭黑分散性变差,拉伸强度和拉断伸长率呈增大趋势,弹性降低,压缩疲劳温升增大;增大并用胶中BR的用量,可以提高胶料的耐屈挠性能。     

TPI的门尼粘度对NR/TPI减震制品性能的影响

研究反式异戊橡胶（TPI）的门尼粘度对天然橡胶（NR）/TPI减震性能的影响。结果表明：与NR硫化胶相比,NR/TPI硫化胶的硬度增大,拉伸性能和抗撕裂性能降低,压缩永久变形减小,在－30,23和70 ℃下的耐屈挠龟裂性能提高,但在100 ℃×48 h热老化后23 ℃下的耐屈挠龟裂性能降低;随着TPI门尼粘度的提高,NR/TPI硫化胶的拉伸性能、撕裂强度和回弹值提高,静态压缩永久变形、动静刚度比和损耗因子减小,耐压缩疲劳性能以及在－30,23和70 ℃下的耐屈挠龟裂性能提高;高门尼粘度TPI在橡胶减震制品中的应用性能更优异。     

反应性液体异戊二烯橡胶增塑丁苯橡胶的性能

以自制液体异戊二烯橡胶(ZLIR)增塑乳聚丁苯橡胶(ESBR),研究ZLIR用量对ESBR性能的影响,并分别与进口液体异戊二烯橡胶(进口LIR)和芳烃油进行对比。结果表明:ZLIR和进口LIR对ESBR胶料的增塑效果优于芳烃油,其能显著改善ESBR的流动性能,降低胶料的加工能耗,在硫化过程中能参与硫化,是一种反应性增塑剂;与芳烃油相比,ZLIR和进口LIR增塑ESBR硫化胶的300%定伸应力(用量为7,10和15份)和0℃下的tanδ较大,压缩疲劳温升、Payne效应、60℃下的tanδ和阿克隆磨耗量较小。ZLIR与进口LIR对ESBR胶料综合性能的影响基本相近。     

国产丁戊橡胶与顺丁橡胶的加工应用性能对比研究

通过与BR的对比,研究了国产丁戊橡胶(BIR)的加工性能、硫化特性、物理性能,并探讨了BIR与BR在胎面胶中的加工应用性能差异。结果表明,BIR硫化速度快,门尼粘度低,加工性能好;BIR硫化胶撕裂强度高,压缩温升低,耐疲劳性好。NR/SBR/BIR并用体系胎面胶硫化速度快,加工性能好;硫化胶的撕裂强度、耐疲劳、抗湿滑等性能均优于NR/SBR/BR并用体系。     

用防老剂及并用防老剂提高轮胎胶料的耐屈挠疲劳和动态臭氧龟裂性能(续完)

(接上期) 3 用各种类型防老剂及其并用物改善NR/BR炭黑胎侧胶料动态屈挠及耐动态臭氧龟裂性能的评价 3.1 胎侧胶 典型的胎侧胶不是使用NR/BR,就是使用NR/BR/SBR,以改善耐割口增长、耐磨耗以及动态屈挠性能.胎侧暴露于外部环境中,因此需要进行防臭氧或氧化龟裂的保护.通常使用2.5～4.0份的烷基芳基对苯二胺,如6PPD或IPPD与混合蜡结合,用于静态和动态耐臭氧龟裂防护以及改善耐屈挠疲劳性能.此外,NR和顺式BR滞后损失小,行驶温度低,这种较低的行驶温度又可以改善屈挠疲劳性能.     

Effect of liquid isoprene rubber on dynamic mechanical properties of emulsionpolymerized styrene/butadiene rubber vulcanizates

The effect of liquid isoprene rubber (LIR) on the dynamic mechanical properties of emulsion‐polymerized styrene/butadiene rubber (ESBR) vulcanizates was investigated by temperature sweep using dynamic mechanical analysis. The introduction of LIR led to ESBR vulcanizates having higher loss factor (tan δ) in the temperature range ? 30 to 0 °C, and lower tan δ in the range 60 to 80 °C. A small amount of LIR‐403 (LIR with carboxyl groups) led to a significant change in tan δ: the addition of LIR‐403 (3 phr) led to a 7.5% increase in tan δ from ? 30 to 0 °C, and a 24.9% decrease in tan δ from 60 to 80 °C. It was found that the introduction of LIR increased the bound rubber content in the ESBR compound. Equilibrium swelling experiments showed that the crosslink density of the vulcanizates increased after the introduction of LIR‐403 or LIR‐50 (general purpose LIR). The change in tan δ from 60 to 80 °C was related to polymer–filler interactions. The characteristic constant of filler–ESBR matrix interaction (m) was calculated. At a given filler volume fraction, the increase in m in the presence of LIR could be well related to the decrease in tan δ from 60 to 80 °C. The influence of LIR on filler network in the ESBR compound was also investigated by strain and temperature sweeps using a rubber processing analyzer. Copyright © 2011 Society of Chemical Industry     

国产溶聚丁苯橡胶T2000R的基本配合性能

根据丁苯橡胶的基础配方,考察了国产溶聚丁苯橡胶( SSBR)(牌号为T2000 R)的基本配合性能,并与乳聚丁苯橡胶(ESBR)(牌号为1502)进行了时比.结果表明,对于SSBR,普通硫黄体系下硫化胶具有较高的撕裂强度和耐屈挠疲劳性能,而半有效硫黄体系下硫化胶的耐磨耗性能和耐压缩疲劳性能最优,相同硫化体系下,SSBR...     

液体聚异戊二烯/天然橡胶复合材料的制备与性能

制备了4种3,4-结构摩尔分数不同的液体聚异戊二烯(LIR),考察了芳烃油及不同3,4-结构摩尔分数的LIR作为增塑剂对于天然橡胶(NR)的交联密度、物理机械性能、动态力学性能及微观结构的影响.结果表明,随着LIR中3,4-结构摩尔分数的增加,NR的交联密度增加.LIR不仅起到增塑的作用,还可与NR形成共交联网络.与芳...     

Co-compatibilising effect of carbon nanotubes and liquid isoprene rubber on carbon black filled natural rubber/polybutadiene rubber blend

Abstract

Bis-(triethoxysilylpropyl)-tetrasulfane functionalised carbon nanotubes (t-CNTs) were used as compatibiliser along with liquid isoprene rubber (LIR) in the natural rubber (NR)/polybutadiene rubber (BR) blend. Their reinforcing and compatibilising effects were evaluated by mechanical, fatigue crack growth resistance properties and blend homogeneity. Scanning electron microscope and transmission electron microscope showed enhanced interfacial adhesion between the binary rubber phases and improved dispersion of the minor phase in the rubber blend respectively with the co-existence of LIR and carbon nanotubes. The tensile strength of the carbon black (CB) filled NR/BR blend reached its optimum when 3 phr CB was replaced with an equal amount of t-CNTs in the presence of 7 phr LIR, while the fatigue crack growth resistance property achieved its maximum in the presence of 3 phr LIR. This interesting co-compatibilisation behaviour of t-CNTs and LIR suggests that t-CNTs have a better effect than CB with the assistance of LIR, which is an effective plasticiser in the NR/BR blend.     

双金属稀土促进剂对丁苯橡胶/天然橡胶胎面胶的影响

通过配位反应制备得到双金属硫化促进剂二乙基二硫代氨基甲酸锌镧配合物(ZnLaDC),在不添加传统活化体系氧化锌(ZnO)/硬脂酸(SA)的情况下,考察了ZnLaDC用量对丁苯橡胶(SBR)/天然橡胶(NR)胎面胶复合材料硫化特性及物理机械性能的影响,并与传统硫化体系二乙基二硫代氨基甲酸锌(ZnDC)/ZnO/SA制备的硫化胶性能进行了对比。结果表明,随着ZnLaDC用量的增加,SBR/NR胎面胶复合材料的硫化特性、压缩疲劳生热性能及耐磨性得到有效提高,当ZnLaDC用量为5份时,复合材料的综合性能最佳。与传统硫化体系ZnDC/ZnO/SA制备的硫化胶相比,采用ZnLaDC制备的硫化胶具有更优异的静态力学性能及耐切割性。     

TBIR改性NR硫化胶的研究

研究了两种牌号反式-1,4-丁二烯-异戊二烯共聚橡胶(TBIR)改性天然橡胶(NR),结果表明,10~50份TBIR与NR共混,并用胶焦烧时间(t10)和工艺正硫化时间(t90)略有延长。相比NR硫化胶,NR/TBIR并用硫化胶力学强度保持在较高范围,屈挠疲劳性能大幅度提高,其中NR/TBIR-20=50/50硫化胶一级屈挠疲劳寿命可提高28.6倍,六级屈挠疲劳寿命可提高11.9倍。DMA结果表明,NR与TBIR具有优异的相容性。RPA及DMA 结果均表明NR/TBIR并用硫化胶具有更低的滚动阻力。综合可知,TBIR是一种高性能的合成橡胶新材料,可显著改善NR的综合性能。     

反式聚辛烯橡胶改性天然橡胶/顺丁橡胶共混胶的性能

研究了反式聚辛烯橡胶(TOR)改性天然橡胶(NR)/顺丁橡胶(BR)(二者质量比80/20)共混胶的性能.结果表明,采用5～15份(质量,下同)TOR改性NR/BR混炼胶的门尼黏度逐渐降低、Payne效应基本不变,共混胶的焦烧时间和工艺正硫化时间延长、硫化速率减慢.相比NR/BR硫化胶,NR/BR/TOR硫化胶的拉伸强...     

生物基液体异戊二烯橡胶对乳聚丁苯橡胶胶料性能的影响

研究生物基液体异戊二烯橡胶（LIR-50）对乳聚丁苯橡胶（ESBR）胶料性能的影响。结果表明：与环保芳烃油相比,LIR-50能更好地改善胶料的加工性能;LIR-50参与了胶料的交联反应,可较好地保持胶料的物理性能;加入适量LIR-50能降低胶料的Payne效应,改善炭黑在胶料中的分散性,在保持胶料低滚动阻力和低生热的同时可明显提高其抗湿滑性能。     

Kaolin modified with sodium salt of rubber seed oil as a reinforcing filler for blends of natural rubber,polybutadiene rubber and acrylonitrile–butadiene rubber

Blends of natural rubber (NR) and synthetic rubbers are widely used in the rubber industry to meet specific performance requirements. Further, the emerging field of organomodified clay/rubber nanocomposites could provide a host of novel materials having a unique combination of properties to meet various stringent service conditions. Previous studies have shown that at very low dosages, china clay (kaolin) modified with sodium salt of rubber seed oil (SRSO) improved the cure characteristics and physico‐mechanical properties of NR. Results of the present study show improved cure characteristics and physico‐mechanical properties for blends of NR with butadiene rubber and nitrile rubber containing 4 phr of SRSO‐modified kaolin as indicated by reduction in optimum cure time along with higher tensile strength, tensile modulus and elongation at break for their vulcanizates as compared to those containing unmodified kaolin. The SRSO‐modified kaolin/rubber nanocomposites showed improved flex resistance, reduced heat build‐up, tan delta and loss modulus and higher chemical crosslink density index, indicating a reinforcing effect of the SRSO‐modified kaolin, enabling the nanocomposites to have potential industrial applications. © 2015 Society of Chemical Industry     

Dynamic properties of star‐shaped,solution‐polymerized styrene–butadiene rubber and its cocoagulated rubber‐filled with silica/carbon black

The dynamic properties, including the dynamic mechanical properties, flex fatigue properties, dynamic compression properties, and rolling loss properties, of star‐shaped solution‐polymerized styrene–butadiene rubber (SSBR) and organically modified nanosilica powder/star‐shaped styrene–butadiene rubber cocoagulated rubber (N‐SSBR), both filled with silica/carbon black (CB), were studied. N‐SSBR was characterized by ¹H‐NMR, gel permeation chromatography, energy dispersive spectrometry, and transmission electron microscopy. The results show that the silica particles were homogeneously dispersed in the N‐SSBR matrix. In addition, the N‐SSBR/SiO₂/CB–rubber compounds' high bound rubber contents implied good filler–polymer interactions. Compared with SSBR filled with silica/CB, the N‐SSBR filled with these fillers exhibited better flex fatigue resistance and a lower Payne effect, internal friction loss, compression permanent set, compression heat buildup, and power loss. The nanocomposites with excellent flex fatigue resistance showed several characteristics of branched, thick, rough, homogeneously distributed cross‐sectional cracks, tortuous flex crack paths, few stress concentration points, and obscure interfaces with the matrix. Accordingly, N‐SSBR would be an ideal matrix for applications in the tread of green tires. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40348.