黏土/天然橡胶纳米复合材料的制备及性能

利用乳液插层法制备了黏土／天然橡胶纳米复合材料,研究了该复合材料的力学性能、应力应变行为、耐磨性、气体阻隔性和耐老化性能。结果表明,黏土／天然橡胶纳米复合材料与高耐磨炭黑(N330)、白炭黑增强橡胶相比,邵尔A型硬度、定伸应力和撕裂强度较高,拉伸强度相当。黏土、N330以及白炭黑对天然橡胶的拉伸结晶有影响,填料用量对材料拉伸强度的影响存在最佳值。黏土／天然橡胶纳米复合材料具有良好的耐磨性、气体阻隔性和耐老化性能。     

Effects of partial replacement of commercial fillers by recycled poly(ethylene terephthalate) powder on the properties of natural rubber composites

Commercial fillers, including carbon black (N550), halloysite nanotubes (HNTs), and precipitated silica, were replaced by recycled poly(ethylene terephthalate) powder (R‐PET) in natural rubber (NR) composites. Five different compositions of NR/N550/R‐PET, NR/HNTs/R‐PET, and NR/silica/R‐PET compounds, i.e., 100/20/0, 100/15/5, 100/10/10, 100/5/15, and 100/0/20 parts per hundred rubber (phr), were prepared on a two‐roll mill. The curing behavior, tensile properties, and morphological characteristics of the natural rubber composites were investigated. The results indicated that the replacement of carbon black, HNTs, and silica by R‐PET decreased the tensile strength and tensile modulus, such that NR/silica/R‐PET composites showed the lowest effect, followed by NR/HNTs/R‐PET and NR/N550/R‐PET composites. The negative effect on these properties can be explained by the decrease of crosslink density. The curing results revealed that with the replacement of carbon black by R‐PET, the scorch time and cure time decreased, but that the NR/HNTs/R‐PET and NR/silica/R‐PET composites exhibited the opposite trend. Scanning electron microscopy investigation of tensile fracture surfaces confirmed that the co‐incorporation of N550/R‐PET improved the dispersion of R‐PET and enhanced the interaction between the fillers and NR matrix more than R‐PET and silica/R‐PET hybrid fillers. J. VINYL ADDIT. TECHNOL., 2012. © 2012 Society of Plastics Engineers     

炭黑对NR／TPI并用胶补强性能的影响研究

研究了炭黑种类扣用量对天然橡胶（NR）／反式-1,4-聚异戊二烯（TPI）并用胶的补强效果。结果表明,合适的混炼工艺下,NR／TPI并用胶中炭黑种类选择N330、其用量为45～50份时,并用胶的拉伸强度、撕裂强度、断裂伸长率最佳,回弹性、硬度适中。屈挠和压缩生热性能较好,达到了对NR／TPI并用胶综合力学性能预期的结果。     

白炭黑/偶联剂补强橡胶的性能研究

研究炭黑N330／白炭黑并用比和偶联荆品种及用量对NR胶料性能的影响。结果表明，硅烷偶联剂Si69对白炭黑的改性效果优于钛酸酯偶联剂；硅烷偶联剂Si69在NR胶料中的最佳用量以补强剂用量的5％～10％为宜；建立的数学模型能较好地拟合炭黑N330／白炭黑并用比和硅烷偶联剂Si69用量与NR胶料各项性能之间的关系。     

配方因素对NR硫化胶弹性的影响

研究硫化体系、助交联剂Si69用量、炭黑品种及其用量对NR硫化胶弹性的影响。结果表明，采用半有效硫化体系，硫化胶的弹性最好；硫化胶弹性随交联密度的增大而提高；随着炭黑粒径的减小或炭黑N330和N550用量的增大，硫化胶的邵尔A型硬度、拉伸强度和300％定伸应力增大，回弹值减小。以最小二乘法拟合出回弹值(y)与邵尔A型硬度(x1)和300％定伸应力(x2)之间的关系式分别为1／y=0．026 503 6 0．000 012 53／xl，1／y=0．064 827 0．000 939 7／x2。     

Design and analysis of single-factor experiments: Analysis of variance of the effect of rice husk ash and commercial fillers in NR compounds

Summary White rice husk ash (WRHA) and black rice husk ash (BRHA) were incorporated into natural rubber (NR) using a laboratory-sized two-roll mill. A conventional vulcanization system was used for curing and physical tests of the NR vulcanized involved determining of tensile and tear resistances. For comparison purposes, precipitated silica (Zeosil-175) and carbon black (N774) were used too. Using the analysis of variance of single-factor experiments, it can be concluded that: BRHA is non-reinforcing filler and its use is limited to 20 phr; WRHA is semi-reinforcing filler and the variation of filler loading (0 up to 50 phr) causes the maximum variation upon tensile strength of NR compounds; and, that although carbon black and silica are reinforcing fillers, a real reinforcement is reached up to 20 phr for tensile strength.     

Properties of natural rubber composites reinforced with silica or carbon black: influence of cure accelerator content and filler dispersion

Filler dispersion is a critical factor in determining the properties of filled rubber composites. Silica has a high density of silanol groups on the surface, which lead to strong filler–filler interactions and a poor filler dispersions. A cure accelerator, N‐tert‐butyl‐2‐benzothiazole sulfenamide (TBBS), was found to improve filler dispersion in silica‐filled natural rubber (NR) compounds. For the silica‐filled NR compounds without the silane coupling agent, the reversion ratio generally increased with increase in TBBS content, whereas those of the silica‐filled NR compounds containing the silane coupling agent and carbon black‐filled NR compounds decreased linearly. The tensile strength of the silica‐filled NR vulcanizate without the silane coupling agent increased as the TBBS content increased, whereas carbon black‐filled samples did not show a specific trend. The experimental results were explained by TBBS adsorption on the silica surface and the improvement of silica dispersion with the aid of TBBS. Copyright © 2003 Society of Chemical Industry     

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.     

填料-橡胶的化学和物理作用及其对补强的影响

研究了炭黑N330和白炭黑与NR／BR的相互作用及其对补强的影响。炭黑N330与NR/BR相互作用的化学交联密度占40％，对拉伸强度的贡献率为82．8％；白炭黑/偶联剂KH—846与NR/BR相互作用的化学交联密度占66．7％，对拉伸强度的贡献率为80．7％；炭黑／白炭黑/偶联剂KH-846与NR/BR相互作用的化学交联密度约占70％，对拉伸强度的贡献率约占94％。3种补强体系对拉伸强度的贡献都是化学作用占优势，贡献率超过80％。     

A comparative study of aging characteristics and thermal stability of oil palm ash,silica, and carbon black filled natural rubber vulcanizates

Filler‐filled natural rubber (NR) vulcanizates were prepared by conventional laboratory‐sized two roll mills and cured using sulfuric system. The effect of thermal aging on physical properties and thermogravimetric analysis (TGA) of oil palm ash (OPA) and commercial fillers (i.e., silica vulkasil C and carbon black N330)‐filled NR vulcanizates at respective optimum loading and equal loading were studied. Before aging, the OPA‐filled vulcanizates showed comparable optimum strength as carbon black‐filled vulcanizates. The hardening of aged filler‐filled NR vulcanizates happened after aging, thereby tensile strength and elongation at break reduced while the modulus increased. Fifty phr carbon black‐filled vulcanizates showed better retention in tensile properties as compared to silica (10 phr) and OPA (1 phr). This was attributed to the addition of different filler loading and this finding was further explained when equal loading of filler‐filled vulcanizates was studied. Fourier transform infra‐red analysis showed chemical structure had changed and tensile fractured surface exhibited smooth appearance due to the deterioration in tensile properties after aging. TGA also denoted the thermal stability was depending on the amount of filler loading. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4474–4481, 2013     

On the potential of organoclay with respect to conventional fillers (carbon black,silica) for epoxidized natural rubber compatibilized natural rubber vulcanizates

Onium modified montmorillonite (organoclay) was compounded with natural rubber (NR) in an internal mixer and cured by using a conventional sulfuric system. Epoxidized natural rubber with 50 mol % epoxidation (ENR 50) in 10 parts per hundred rubber (phr) was used as a compatibilizer in this study. For comparison purposes, two commercial fillers: carbon black (grade N330) and silica (grade vulcasil‐S) were used. Cure characteristics were carried out on a Monsanto MDR2000 Rheometer. Organoclay filled vulcanizate showed the lowest values of torque maximum, torque minimum, scorch, and cure times. The kinetics of cure reaction showed organoclay could behave as a cocuring agent. The mechanical testing of the vulcanizates involved the determination of tensile and tear properties. The improvement of tensile strength, elongation at break, and tear properties in organoclay filled vulcanizate were significantly higher compared to silica and carbon black filled vulcanizates. In terms of reinforcing efficiency (RE), organoclay exhibited the highest stiffness followed by silica and carbon black filled vulcanizates. Scanning electron microscopy revealed that incorporation of various types of fillers has transformed the failure mechanism of the resulting NR vulcanizates compared to the gum vulcanizates. Dynamic mechanical thermal analysis (DMTA) revealed that the stiffness and molecular relaxation of NR vulcanizates are strongly affected by the filler–rubber interactions. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2438–2445, 2004     

An investigation on the reinforcing potential of red earth as filler for natural rubber compounds

Locally sourced red earth (RE) was air‐dried, pulverized, and screened with a sieve of mesh size 75 nm. It was characterized in terms of its moisture content, loss on ignition, silica content, iodine adsorption number, oil absorption, pH, and metal oxide compositions. Natural rubber, standard Nigerian rubber used for this work was first characterized in terms of its dirt, ash and nitrogen contents, volatile matter, plasticity retention index, and Mooney viscosity. The RE was applied as filler wholly and in blends with standard carbon black, CB (N330) filler in the natural rubber compounding using efficient vulcanization system. The cure and the physicomechanical properties of the compounds and vulcanizates were, respectively, measured as function of filler loading. The results were compared with those of the standard carbon black (N330)‐filled natural rubber. It was found, that the RE‐filled natural rubber showed substantial reinforcement of the rubber, though inferior to carbon black (N330) filled vulcanizates, the tensile strength of the carbon black‐filled vulcanizates is about one half times that of the RE‐filled vulcanizates. The tensile properties of the RE‐filled vulcanizates improved markedly by blending the RE‐filler with the carbon black (N330). © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Synergistic effect of carbon black and carbon–silica dual phase filler in natural rubber matrix

In this article, the synergistic effects of carbon black (CB) and modified carbon–silica dual phase filler (MCSDPF) on the properties of natural rubber (NR) were investigated. MCSDPF was prepared by modifying carbon–silica dual phase filler (CSDPF) with bis(3‐triethoxysilylpropyl)tetrasulphane (Si‐69). Fourier transform infrared spectroscopy and thermogravimetric analyzer analyses revealed that Si‐69 was successfully grafted to CSDPF. NR‐based compounds containing various combinations of MCSDPF and CB were prepared through a mechanical mixing. Investigations of mechanical properties, ageing resistance, abrasion resistance, dynamic mechanical properties, and morphology of tear fractured surface of MCSDPF/CB/NR vulcanizates were conducted. Our study shows that adding MCSDPF led to significant improvement in the tear resistance, fatigue life, and elongation at break of MCSDPF/CB/NR vulcanizates. Optimum stoichiometric combination of MCSDPF and CB inside the NR matrix was derived (ratio of MCSDPF and CB in wt% = 15/50), which showed synergistic effects of MCSDPF upon CB that was ultimately reflected in their tensile strength, wet skid resistance, and rolling resistance. POLYM. COMPOS., 35:1466–1472, 2014. © 2013 Society of Plastics Engineers     

Distribution of carbon black in natural rubber/acrylic rubber blends

Distributions of carbon black in 30/70% (w/w) natural rubber (NR)/acrylic rubber (ACM) blends were investigated as a function of the carbon black content and type using a dynamic mechanical thermal analysis (DMTA) technique. Two different types of carbon black (N220 and N330) were used, and 10–50 phr carbon black was compounded to the rubber blends. From the DMTA thermograms of various blends, the weight fractions of carbon black in the NR and ACM phases were calculated. Carbon black was unevenly distributed in the rubber blend. It preferred to migrate into the NR phase, regardless of the amount of carbon black that was used. By increasing the carbon black content, the weight fraction of carbon black in the NR phase decreased whereas that in the ACM phase increased. A change in the type of carbon black from N220 to N330 significantly decreased the weight fraction of carbon black in the NR phase, but it was not sufficiently strong to affect the tensile properties and hardness of the rubber blend. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:248–256, 2006     

炭黑在沥青基短切碳纤维补强天然橡胶中的作用

研究炭黑及沥青基短切碳纤维表面臭氧改性对碳纤维填充天然橡胶(NR)硫化胶物理性能的影响。结果表明:臭氧改性后,碳纤维的涂覆层基本去除且表面粗糙度明显增加;碳纤维/NR复合材料拉伸断面中碳纤维表面光滑且与NR发生明显脱粘,复合材料物理性能较低;填充30份炭黑N330后,碳纤维/NR复合材料物理性能显著提高,炭黑/短纤维/NR复合材料和炭黑/臭氧改性碳纤维/NR复合材料的拉伸强度分别达到18.6和26.9 MPa,较碳纤维单独填充时分别提高了431%和627%;碳纤维与炭黑具有类似的微观结构,炭黑在碳纤维补强NR时起到桥梁作用,从而大大增强了两者间的界面强度。     

Effect of carbon black on properties of rubber nanocomposites

Polymer based nanocomposites were prepared using brominated poly(isobutylene‐co‐paramethylstyrene) (BIMS) rubber and octadecyl amine modified montmorillonite nanoclay. The effect of nature and loading of carbon black on these nanocomposites and the control BIMS was investigated thoroughly using X‐ray diffraction technique (XRD), Fourier transform infrared spectroscopy (FTIR), and mechanical properties. The addition of 4 parts of the modified nanoclay to 20 phr N550 carbon black filled samples increased the tensile strength by 53%. Out of the three different grades of carbon black (N330, N550, and N660), N550 showed the best effect of nanoclay. Optimum results were obtained with the 20 phr filler loading. For comparison, china clay and silica at the same loading were used. Fifty‐six and 46% improvements in tensile strength were achieved with 4 parts of nanoclay added to the silica and the china clay filled samples, respectively. N330 carbon black (20 parts) filled styrene butadiene rubber (SBR) based nanocomposite registered 20% higher tensile strength with 4 parts of the modified nanoclay. In all the above carbon black filled nanocomposites, the modulus was improved in the range of 30 to 125%. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 443–451, 2005     

炭黑对CR/TPI并用胶性能的影响

研究了炭黑种类及用量对CR/TPI并用胶的影响.结果表明:随着炭黑粒径的增大,混炼胶焦烧时间有增大的趋势,正硫化时间也随之延长;硫化胶交联程度降低;硫化胶的拉伸强度、断裂伸长率、压缩生热温升、屈挠性能和炭黑分散度随之降低;常温下回弹性能、磨耗性能提高;硫化胶的老化性能略有提高.添加炭黑N330硫化胶的综合性能最好.随着炭黑N330用量的增加,硫化胶拉伸强度先增大后减少,炭黑40份左右达到最大值,断裂伸长率减少,磨耗性能和屈挠性能降低,压缩生热温升、邵尔A硬度增大,常温下回弹性能提高.     

白炭黑/炭黑并用对轮胎胎面胶性能的影响

研究了白炭黑175Gr分别与4种炭黑并用对轮胎胎面胶加工性能、物理机械性能和动态物理机械性能的影响。研究表明,随着炭黑粒径的增大和结构度的提高,白炭黑175Gr/炭黑填充的胶料正硫化时间都缩短;白炭黑175Gr/炭黑N234并用时,其胶料拉伸强度和拉断伸长率都最高;白炭黑175Gr分别与炭黑N220和炭黑N550并用时,两种胶料的回弹性和压缩疲劳性都较好;白炭黑175Gr/炭黑N220并用后,其胶料的Payne效应较小,滞后损耗因子最低。     

不同白炭黑填充充油溶聚丁苯橡胶的性能

考察了不同白炭黑对填充充油溶聚丁苯橡胶的硫化特性、交联密度、常规力学性能及动态力学性能的影响,分析了白炭黑在胶料中的分散状况,并与炭黑增强胶料进行了对比.结果表明,白炭黑粒径越小、分散性越好,所填充硫化胶的拉伸强度越高,但动态力学性能较差;高分散性白炭黑Z 1165 MP适用于要求高强度、高耐磨的胶料,而粒径相对较大的白炭黑Z 125 Gr适用于要求动态力学性能较好的橡胶制品;白炭黑可达到与炭黑相当的增强效果,与炭黑相比,其在胶料中分散困难,易团聚,因此必须选择合适的混炼工艺才能保证充分发挥其增强作用.     

HNBR4种补强填充体系的研究

分别研究了炭黑N330,炭黑N550,炭黑N660和炭黑N774对氢化丁腈橡胶（HNBR）硫化特性和力学性能的影响,并考察了4种炭黑在HNBR中的分散度和Payne效应。结果表明,炭黑N550的胶料焦烧时间和正硫化时间均最长,分散度最好。随着炭黑粒径的逐渐增大,硫化胶拉伸强度、定伸应力和硬度均逐渐减小,拉断伸长率却逐渐增大。4种炭黑胶料的Payne效应强弱顺序为炭黑N330〉炭黑N550〉炭黑N660〉炭黑N774。