炭黑/白炭黑补强硫化胶的疲劳破坏特性

应用断裂力学的方法解析和预测了天然橡胶采用高耐磨炭黑与白炭黑并用补强体系在疲劳过程中形变能密度的变化，疲劳破坏寿命、断裂特征和能量释放率。结果表明：在天然橡胶中采用高耐磨炭黑与白炭黑并用补强体系，随白炭黑用量的增加，胶料疲劳破坏寿命延长，胶料内部潜在缺陷减小，裂纹扩展速度减慢，形变能密度下降缓慢，胶料的能量释放率增加。     

炭黑补强NR硫化胶疲劳破坏特性的研究

用断裂力学方法研究炭黑N110，N220和N330补强NR硫化胶的疲劳破坏特性。结果表明，随着疲劳时问的延长，3种炭黑补强硫化胶的拉断形变能密度均减小，且炭黑粒径越小，硫化胶的拉断形变能密度降幅越大；炭黑粒径越小的硫化胶内部潜在缺陷越小，但抗裂纹扩展性能越差，疲劳寿命越短；3种炭黑补强硫化胶的疲劳寿命方程均能较准确地预测其疲劳寿命。     

补强体系对NR硫化胶疲劳破坏特性的影响

用断裂力学方法研究炭黑N330、炭黑N330/白炭黑和白炭黑补强NR硫化胶的疲劳破坏特性.结果表明,与炭黑N330和炭黑N330/白炭黑补强的NR硫化胶相比,白炭黑补强的NR硫化胶疲劳寿命较长,内部潜在缺陷较少,抗裂纹扩展性能较好;随着疲劳时间的延长,NR硫化胶拉断时的应变能密度减小;疲劳寿命方程能够快速、准确地预测NR硫化胶的疲劳寿命.     

偶联剂Si69对炭黑补强NR硫化胶性能的影响

研究了偶联剂Ｓｉ６９用量对炭黑补强ＮＲ胶料硫化特性、硫化胶物理性能和热氧老化性能的影响,并用傅立叶变换红外光谱（ＦＴＩＲ）研究了硫化胶在拉伸疲劳过程中结构的变化。结果表明,当Ｓｉ６９的用量为炭黑用量的１／１０左右时,硫化胶的拉伸强度和３００％定伸应力具有最大值,且耐老化性能最好。胶料中加入Ｓｉ６９,使体系中的多硫键数量增多,从而改善了体系的交联键类型和硫化胶性能。在拉伸疲劳过程中,随着疲劳过程的进行,多硫键数量减少,而单硫键数量增多,再次证明硫化胶具有自愈合能力。     

白炭黑补强POE硫化胶性能的研究

研究了白炭黑对POE硫化胶补强性能的影响。结果表明，POE随着交联程度的增加，力学性能逐渐下降；白炭黑对POE硫化胶补强效果显著，其用量20份以上时，拉伸强度、撕裂强度较高，扯断永久变形率明显降低。     

改性白炭黑对丁腈橡胶/炭黑硫化胶弹性的影响

研究了用硅烷偶联剂Kagevest25改性的白炭黑对NBR／炭黑硫化胶弹性的影响。结果表明,当改性白炭黑填充量为25份(质量,下同)、炭黑为55份时,NBR／炭黑硫化胶的综合力学性能最佳。试样扯断伸长率、回弹性、压缩永久变形和扯断永久变形分别为325％,16．7％,20．7％,4％,25℃和70℃下tan占分别是0．1739和0．1429,在老化前后较填充未改性白炭黑均有更好的弹性。     

白炭黑和白炭黑/炭黑并用补强末端基改性溶聚丁苯橡胶/顺丁橡胶并用胶的性能研究

研究白炭黑和白炭黑/炭黑并用补强单、双末端基改性溶聚丁苯橡胶(SSBR)/顺丁橡胶(BR)并用胶的性能。结果表明:SSBR末端基改性,尤其是双末端基改性,能够显著提高SSBR与白炭黑的相容性,从而提高SSBR/BR并用胶的综合物理性能和动态力学性能;SSBR的末端基改性效果在白炭黑/炭黑并用时不能有效发挥,白炭黑/炭黑并用补强末端基改性SSBR/BR并用胶的综合物理性能和动态力学性能均逊于白炭黑补强末端基改性SSBR/BR并用胶。     

白炭黑填充SSBR T1534硫化胶在拉伸疲劳过程中的性能变化

研究白炭黑填充充油溶聚丁苯橡胶(SSBR T1534)硫化胶在拉伸疲劳过程中的性能变化,并与白炭黑填充非充油SSBR(SSBR T2000R)硫化胶进行对比.结果表明:SSBR T1534硫化胶的拉伸性能在拉伸疲劳过程中明显下降;其交联密度随拉伸疲劳次数的增加呈下降趋势,而SSBR T2000R硫化胶则变化不大;SSBR T1534硫化胶的损耗因子(tanδ)峰值显著增大,峰变宽,而SSBR T2000R硫化胶的tanδ峰值随拉伸疲劳次数的增加略有增大,峰明显变宽;当拉伸疲劳次数相同时,SSBR T1534硫化胶的储能模量(E')及Payne效应均低于SSBR T2000R硫化胶,且其E',损耗模量和tanδ值在拉伸疲劳过程中的差别不大.     

动态伸张疲劳对SIBR硫化胶结构及性能的影响

本文研究了集成橡胶动态疲劳过程中性能以及结构的变化情况;研究指出,在疲劳过程中,集成橡胶发生了分子链的断裂,断裂后的自由端链在周期性应力的作用下与空气中的氧气作用生成了羰基;动态疲劳过程中集成橡胶的物理机械性能明显减小;填充SIBR硫化胶交联密度随着疲劳次数的增大逐渐降低;动态力学性能也发生了显著变化。     

ESBR硫化胶交联结构及动态粘弹性在拉伸疲劳过程中的变化

研究炭黑和白炭黑填充乳聚丁苯橡胶硫化胶拉伸疲劳过程中交联结构和动态粘弹性的变化。结果表明,炭黑填充胶料的拉伸性能在拉伸疲劳次数低于50万次时下降明显,而白炭黑填充胶料在50万～100万次之间下降幅度较大;随着拉伸疲劳次数的增加,两种胶料的交联密度均减小;拉伸疲劳次数达到200万次时,炭黑填充胶料的tanδ峰宽明显增大,而白炭黑填充胶料在拉伸疲劳次数50万次以上tanδ峰就明显增高、增宽;炭黑填充胶料疲劳后高弹态的tanδ变化不大,而白炭黑填充胶料tanδ显著增大;白炭黑填充胶料的Payne效应较炭黑填充胶料大,且拉伸疲劳后Payne效应明显减小。     

Fatigue life prediction of filled polypropylene based on creep rupture

To predict the fatigue performance of talc-filled polypropylene in engineering applications, a simple relationship using constant stress data to predict the cycles-to-failure (N_f) was developed: where k and n are constants from creep rupture tests, v is the cyclic frequency (≤1 Hz to avoid self-heating), f(n) is a function that accounts for the wave form, and a is the peak cyclic stress with a zero minimum stress. For stress concentrations produced by central holes, σ is taken as the average net section stress and the effect of the stress concentration is ignored. Extensive tests were used to verify this expression for cyclic frequencies of 1.0 and 0.1 Hz, sinusoidal and triangular waveforms, stress concentrations produced by small and large holes, and 20 and 40 percent talc filler content.     

偶联剂与混炼工艺对炭黑填充NBR胶料性能的影响

研究偶联剂Si69和KH-550与混炼工艺对炭黑填充NBR胶料硫化特性、表观交联密度、物理性能和动态性能的影响。结果表明,偶联剂的加入能够延长胶料的t90,经高温混炼后的NBR胶料的焦烧时间缩短,t90延长;偶联剂能够增大NBR胶料的表观交联密度和炭黑-橡胶间的相互作用,经高温混炼后作用更加明显,硫化胶的物理性能提高;加入偶联剂KH-550并经高温辊改性后的NBR硫化胶具有更好的耐热老化性能。偶联剂Si69或KH-550能够改善NBR硫化胶的动态性能,加入偶联剂KH-550并经高温改性后性能较佳。     

炭黑与白炭黑增强聚烯烃弹性体硫化胶的比较

研究了炭黑、白炭黑对聚烯烃弹性体(POE)硫化胶的增强作用,考察了交联剂过氧化二异丙苯(DCP)和炭黑及白炭黑的用量对POE硫化胶物理机械性能的影响,并用扫描电子显微镜对其微观结构进行了观察.结果表明,用DCP交联POE,POE的主要物理机械性能比未交联前有所下降;用炭黑、白炭黑增强POE硫化胶,其物理机械性能显著提高,说明增强效果明显,炭黑、白炭黑最佳用量分别为60份和40份.     

Preparation and properties of carbon black filled EPDM/POE thermaplastic vulcanizates

TPVs filled with different amounts (0–50 phr) of carbon black were prepared via melt mixing by dynamic vulcanization in Haake plasticorder at 150°C and 40rpm and then the properties of them were studied. Torque-time curves showed that the curing degree reached a biggest value at 10 phr and then decreased with the increase of filling content while the curing rate was always rising. Mechanical properties such as tensile strength, tear strength, modulus as well as hardness increased with the increment of carbon black content while the tension set at break was reduced dramatically. Two phase morphology was observed by SEM photographs and the effect of carbon black on curing extent was testified. To illuminate the effect of carbon black, curometer curves and carbon black dispersion pictures were also analyzed. Rubber processing analyzer (RPA) experiments proved that there was a progressive nonlinear behavior, which was more and more clearly expressed with the increment of carbon black content and could be explained via the Payne effect. But the TPVs containing highest carbon black exhibited the fastest drop of G′ with increasing strain amplitude as obtained from the value of G₀′ − G_∞′. The order of tanδ at different carbon black content was tanδ (10 phr) < tanδ (0 phr) < tanδ (30 phr) < tanδ (50 phr) at lower strain amplitude. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Rubber fatigue life prediction using a random forest method and nonlinear cumulative fatigue damage model

In this study, a random forest machine-learning method is introduced on the basis of the analysis of measured constant amplitude stress fatigue data. This method aims to predict rubber fatigue life under constant amplitude stress. Strain mean value, strain amplitude, and strain ratio are used as independent variables, and the prediction model of rubber fatigue life under constant amplitude stress is established. A nonlinear cumulative fatigue damage model is proposed to calculate rubber fatigue life under the variable amplitude stress. Results show that the random forest method has high precision and generalization capability for rubber fatigue life prediction under constant amplitude stress and the nonlinear cumulative fatigue damage model could be employed to calculate the fatigue life of rubber under variable amplitude stress with enough accuracy according to the constant amplitude stress fatigue life data. This research can provide a reference for rubber fatigue life prediction. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48519.     

Effect of filler network on dynamic viscoelastic properties of uncured polymethylvinylsiloxanes filled with silica and carbon black

Dynamic properties of polymethylvinylsiloxane (PMVS) filled with filler‐blends composed of carbon black (CB) and silica (SiO₂) were investigated using an advanced rheometric expansion system. A variety of weight fraction of CB to SiO₂ were 0/100, 10/90, 30/70, 50/50, 70/30, 90/10, and 100/0, and a bifunctional organsilane, bis(3‐triethoxysilylpropyl)tetrasurfane, was used to facilitate the filler dispersion. The results reveal that the incorporation of CB/SiO₂ filler‐blends into PMVS result in a reduced Payne effect. This effect reaches a minimum when the ratio of CB/SiO₂ approaches 1, and then it began to rebound with the ratio increase. Meanwhile, a characteristic Newtonian viscosity plateau appearing in low frequencies also significantly decreases, depending on the amount of CB or SiO₂ added. On the basis of a simplified Fowke model, we ascribe this phenomenon to the deteriorated filler network, which is predominantly induced by the totally different surface activity between CB and SiO₂. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3477–3482, 2006     

炭黑/白炭黑双相填料补强BIIR/PP热塑性弹性体的性能研究

通过动态硫化工艺制备了溴化丁基橡胶（BIIR）/聚丙烯（PP）热塑性弹性体,研究了加工时间、填料、硫化剂对弹性体力学性能的影响。结果表明,动态硫化制备热塑性弹性体的时间约为13 min;使用炭黑N330/白炭黑双相填料的热塑性弹性体具有较好的力学性能;在氧化锌、硫磺、溴化辛基酚醛树脂及硫磺/溴化辛基酚醛树脂并用硫化体系中,溴化辛基酚醛树脂硫化的热塑性弹性体力学性能最佳。     

NBR对白炭黑-炭黑填充补强SSBR性能的影响

研究了不同用量的丁腈橡胶(NBR)对白炭黑-炭黑填充溶聚丁苯橡胶(SSBR)性能的影响。研究证明：随着NBR用量的增加,混炼胶硫化速度加快,正硫化时间呈减小趋势,压缩生热和永久变形率缓慢增大,拉伸强度略有下降,但是可以提高耐磨耗性能;当加入NBR的量为4份时可以同时优化胶料湿滑性能和滚动阻力。     

Effect of the blooming of chemical curatives on the cyclic fatigue life of natural rubber filled with a silanized silica nanofiller

When partly soluble chemical curatives are mixed with raw rubber, they migrate to the rubber surface, which can be detrimental to the rubber properties. Two rubber compounds with different amounts of curatives were prepared by mixing natural rubber with a high loading of precipitated amorphous white silica nanofiller. The silica surfaces were pretreated with bis(3‐triethoxysilylpropyl)‐tetrasulfide coupling agent to chemically adhere silica to the rubber. The chemical bonding between the filler and rubber was optimized via the tetrasulfane groups of bis(3‐triethoxysilylpropyl)‐tetrasulfide by adding accelerator and activator. The rubber compounds were cured and stored at ambient temperature for up to 65 days. One compound showed extensive blooming as a function of storage time. The cyclic fatigue life of the rubber vulcanizates was subsequently measured at a constant strain amplitude and test frequency at ambient temperature. The blooming of the chemical curatives reduced the cyclic fatigue life of the rubber vulcanizate by more than 100%. The migrated chemical curatives produced a thin layer approximately 15 μm in size beneath the rubber surface. When the rubber was stressed repeatedly in the fatigue test, cracks initiated in this layer and subsequently grew, causing the fatigue life of the vulcanizate to decrease. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011