Akron Abrasion Research Articles

Effect of alkaline protease content on the structure and properties of natural rubber

AbstractThe solidification technology of natural rubber exerts a significant impact on the properties of natural rubber. The solidification technology of alkaline protease has been highly valued by researchers at home and abroad because of its good solidification effect, excellent vulcanization performance, and low pollution. In this study, the effects of alkaline protease solidification technology and enzyme dosage on the structure and properties of natural rubber were investigated and compared with those of formic acid solidification technology. The solid‐state NMR results showed that increasing the enzyme dosage increased the molecular chain entanglements in the raw rubber. The gel content test results showed that the natural network structures (i.e. gels) increased after the addition of alkaline protease. The test results of the vulcanization characteristics showed that the addition of alkaline protease significantly shortened the positive vulcanization time. The Mw was the largest at an enzyme dosage of 0.07%. The test results for mechanical properties showed that the mechanical properties were best when the enzyme dosage was 0.07%. In addition, as the alkaline protease dosage increased, the Akron abrasion volume of natural rubber decreased, and the Akron abrasion volume was the lowest at an enzyme dosage of 0.07%.

Effect of Varied Cure Temperature on the Cure Behavior, Mechanical Properties and Heat Build-Up of Solid Tire Tread Compound Containing Different Particles Sizes of Ground Tire Rubber

This work investigates the effect of variation in vulcanization temperature on the cure behavior, tensile properties, tear strength, hardness, Akron abrasion loss and heat build-up of vulcanized tire tread compound in which the total rubber was replaced with 10% and 20% ground tire rubber (GTR) of 40, 60 and 80 mesh sizes. The first step was the characterization of the GTR using optical microscopy and a thermogravimetric analyzer. The first step of mixing each rubber compound was carried out using an internal mixer (Brabender) at 60°C and 40 rev/min rotor speed and the second step was done on a two-roll mill. The mooney viscosity of each rubber compound was investigated. the cure behavior of the rubber compounds was studied at 140°C, 150°C, and 160°C respectively. Results show that the introduction of GTR reduced vulcanization time, while increased cure temperature resulted in a lower vulcanization time. No significant difference was observed in the vulcanization time at a particular temperature of the rubber sample with different particle sizes and varied amounts of GTR. The introduction of ground tire rubber in the rubber vulcanizate however resulted in decreased tensile strength, tear strength and elongation, and increased hardness, abrasion resistance, modulus and heat build-up. An increase in the vulcanization temperature from 140°C to 150°C and 160°C did not impart a significant reduction in the tensile strength of the vulcanizates containing GTR. Vulcanization at higher temperatures resulted in reduced hardness, and modulus, slightly increased abrasion loss and increased elongation of the vulcanizates containing GTR. The heat build-up increased as the cure temperature increased. Generally, the control sample with no content of ground tire rubber exhibited the best properties. If GTR is to be introduced in rubber matrix at an amount up to 20%, the results suggest that 60 mesh size particles will impart better properties. The optimal vulcanization temperature recommended based on the findings from the work is 150°C.

Exfoliation, hydroxylation and silanization of two-dimensional (2D) montmorillonites (MMTs) and evaluation of the effects on tire rubber properties

In this work, effects of two-dimensional (2D) montmorillonite (MMT) on physical/mechanical/dynamic properties and rolling resistance of a model tire rubber were assessed. To achieve proper performance of MMTs in rubber compound, the layered stacks were initially exfoliated using sonication in deionized water. Pure MMTs showed a great tendency to aggregation in rubber matrix due to their superhydrophilic nature, so they were functionalized using 5 M NaOH solution to create surface OH groups for subsequent modification. The functionalized MMTs were silane modified with vinyltrimethoxysilane (VTMS) at different concentrations, finally, vinyl groups caused hydrophobicity and increment of water contact angle (WCA) from 35° to 92° in comparison with pure MMTs. The performance of tire rubber blends (TRBs) containing the pure MMTs, exfoliated MMTs and silanized MMTs was compared to the pristine rubber. Silanization of MMT caused a 140.47 % increase in the crosslink density of TRB nanocomposite. The results showed that the optimum curing time of rubber decreased by 56 s compared to the pristine TRB. The modulus of 100 and 300 % increased by 103 and 20 % for sample that contained silane modified MMTs, respectively. The elongation at break decreased by 7 % for the modified nanocomposite compared to the pristine TRB. Also, the storage modulus and transition glass temperature of nanocomposite containing silanized MMTs increased by 54 % and 7 °C compared to the control TRB, respectively. The rolling resistance in the tire (i.e. C-s5-MMT1) demonstrates a prominent reduction of 19.42 %, accomplished with a 30.28 % decrease in power loss, 85.07 % Akron abrasion loss, and the lowest Heat-Build up, as compared with the pure tire (i.e. C-Ctrl).

Improving Dispersion of Carbon Nanotubes in Natural Rubber by Using Waterjet-Produced Rubber Powder as a Carrier.

Carbon nanotube (CNT), as reinforcing agents in natural rubber (NR), has gained a large amount of consideration due to their excellent properties. Uniform dispersion of CNT is the key to obtaining high-performance NR nanocomposites. In this contribution, a novel ultrasonic grinding dispersion method of CNT with waterjet-produced rubber powder (WPRP) as a carrier is proposed. Microscopic morphologies show that a Xanthium-like structure with WPRP as the core and CNTs as the spikes is formed, which significantly improves the dispersion of CNT in the NR matrix and simultaneously strengthens the bonding of the WPRP and NR matrix. With the increase in the WPRP loading, the Payne effect of CNT/WPRP/NR composites decreases, indicating the effectiveness of the dispersion method. The vulcanization MH and ML value and crosslinking density increase with the increase in the WPRP loading, whereas the scorch time and cure time exhibit a decreasing trend when the WPRP loading is less than 15 phr. It is found that the CNT/WPRP/NR composites filled with 5 phr WPRP have a 4% increase in 300% modulus, a 3% increase in tensile strength, while a 5% decrease in Akron abrasion loss, compared to CNT/NR composites.

Natural rubber reinforced with super-hydrophobic multiwalled carbon nanotubes: obvious improved abrasive resistance and enhanced thermal conductivity

Abstract Polyurethane chain was successfully grafted onto carbon nanotubes, affording polyurethane-functionalized multiwalled carbon nanotubes (P-MWCNTs) with super-hydrophobic property, which shows improved abrasive resistance obviously and enhanced thermal conductivity for natural rubber (NR) vulcanizate. Under the optimized conditions, the akron abrasion loss of NR vulcanizate combined with 5 parts per hundred rubber (5 phr) P-MWCNTs is 0.9 cm3/1.61 km compared to 2.96 cm3/1.61 km of pristine NR vulcanizate. The thermal conductivity of NR vulcanizate combined with 5 phr P-MWCNTs has been improved by 40.3% compared to that of pristine NR vulcanizate. The decreased height of the maximum tan δ peak shows that P-MWCNTs can reduce the heat buildup and damping capability of NR/P-MWCNTs composites. The good dispersion of P-MWCNTs with a continuous network, particularly at high loading (5 phr) in the NR composites, was evidenced from transmission electron microscopy (TEM).

Double‐layer modified silica with potential reinforcement for solution polymerized styrene‐butadiene rubber/butadiene rubber composite

AbstractSilica was dual layer surface‐capped by hexamethyldisilamide (HMDS) and epoxy‐terminated ethylene‐vinyl acetate copolymer (EVA) via an in situ synthesis route to acquire greatly improved compatibility and interfacial interactions with solution polymerized styrene‐butadiene rubber/butadiene rubber (SSBR/BR). The as‐prepared HMDS/EVA‐SiO2 was used to reinforce SSBR/BR matrix so as to improve the wet skid resistance and wear resistance, and reduce the rolling resistance of the rubber–matrix composite. Besides, the as‐fabricated HMDS/EVA‐SiO2 was characterized by Fourier transform infrared spectrometry and transmission electron microscopy; and the tensile strength and tear resistance of the HMDS/EVA–SiO2/SSBR/BR composites were measured with a universal testing machine. Moreover, an Akron abrasion test was performed to determine the abrasion volume of SiO2–SSBR/BR composites; and a rotary rheometer was run to evaluate the dynamic mechanical properties of the vulcanized rubber‐matrix composites. Findings indicate that the EVA resin latex synthesized by emulsion polymerization can effectively improve the compatibility and forms a permeability layer between the rubber and nano‐silica of the composites. The as‐fabricated HMDS/EVA‐SiO2‐SSBR/BR composite exhibits greatly improved wear resistance and wet skid resistance as well as significantly reduced rolling resistance, showing potential as green tire tread material with increased security and service life as well as reduced energy consumption.

Multiple Intermolecular Interaction to Improve the Abrasion Resistance and Wet Skid Resistance of Eucommia Ulmoides Gum/Styrene Butadiene Rubber Composite.

A rubber composite was prepared by using methyltriethoxysilane (MTES) to modify silica (SiO2) and epoxidized eucommia ulmoides gum (EEUG) as rubber additives to endow silica with excellent dispersion and interfacial compatibility under the action of processing shear. The results showed that compared with the unmodified silica-reinforced rubber composite (SiO2/EUG/SBR), the bound rubber content of MTES-SiO2/EEUG/EUG/SBR was increased by 184%, and its tensile strength, modulus at 100% strain, modulus at 300% strain, and tear strength increased by 42.1%, 88.5%, 130.8%, and 39.9%, respectively. The Akron abrasion volume of the MTES-SiO2/EEUG/EUG/SBR composite decreased by 50.9%, and the wet friction coefficient increased by 43.2%. The wear resistance and wet skid resistance of the rubber composite were significantly improved.

NNI‐SMOTE‐XGBoost: A Novel Small Sample Analysis Method for Properties Prediction of Polymer Materials

AbstractDespite the usage of machine learning accelerating the properties prediction of polymer materials, obtaining a large number of samples to achieve accurate and fast predictions remains a challenge because of the complex and lengthy experimental process. In this work, an advanced prediction model for the small sample analysis is presented by an ensemble learning algorithm called extreme gradient boosting (XGBoost) based on nearest neighbor interpolation (NNI) and synthetic minority oversampling technique (SMOTE). Different from directly using small sample prediction algorithms, a brand‐new idea based on feature engineering is proposed. NNI algorithm is used to interpolate the original data set to solve the data insufficiency. SMOTE algorithm is used to solve the data imbalance problem by increasing minority samples. The expanded data set is used to build an XGBoost prediction model. A model for predicting Akron abrasion of rubber through mechanical properties is established via the proposed method. The original data set is expanded to 710 samples through two different interpolations. Experimental results show that better prediction accuracy and generalization ability are obtained than traditional algorithms. The Akron abrasion is found to be the most related to the elongation at break of polymer materials.

Influence of Carbon Black on Aging Properties of Natural Rubber

The influence of carbon black on the aging properties of NR was studied by adding different grades and contents of carbon black. The results show that the hardness, tensile strength and tear strength of NR increased with the increase of carbon black level and content, while the elongation at break and Akron abrasion decreased. After hot air accelerated aging and ultraviolet aging, the tensile strength, elongation at break and Akron abrasion of NR decreased, the tear strength first decreased and then increased, and the shore hardness gradually increased. With the increase of carbon black grade and quantity, the change rate of natural rubber aging properties, such as shore hardness, tensile strength, elongation at break, tear strength and Akron abrasion, became smaller and smaller.

Preparation of hexamethyl disilazane-surface functionalized nano-silica by controlling surface chemistry and its “agglomeration-collapse” behavior in solution polymerized styrene butadiene rubber/butadiene rubber composites

A series of nano-silicas with varying content of grafted hexamethyl disilazane (HMDS) modifier were prepared by liquid phase in-situ surface modification method in combination with granulation technology. The effect of the as-prepared nano-silica as fillers on the mechanical properties and abrasion resistance of solution polymerized styrene butadiene rubber (SSBR)/butadiene rubber (BR)-matrix composites were investigated. It was found that the content of the surface hydroxyl of the as-prepared organic-inorganic hybrids, HMDS-capped nano-silica, can be well tuned by adjusting the modifier dosage. The resultant HMDS-capped nano-silica have greatly improved dispersibility in rubber matrix as well as highly enhanced compatibility and interfacial interaction with the rubber matrix, which is favorable for improving the mechanical properties and abrasion resistance of the SSBR/BR-matrix composites. Particularly, the SSBR/BR-matrix composite filled with HMDS-capped nano-silica obtained at a modifier dosage of 20% (mass fraction) exhibits greatly improved mechanical properties and wet skid resistance(12.0%) as well as significantly reduced rolling-resistance(30.4%) and Akron abrasion(18.4%) as compared with the one filled with unmodified nano-silica. The present approach, with good access to surface chemistry manipulation of nano-silica, could help to promote the application of functionalized nano-silica in tire industry.

Preparation and performance of oleylamine modified silica‐reinforced natural rubber composites

AbstractOleylamine (OA) modified silica (SiO2‐g‐OA) was prepared using γ‐(2,3‐epoxypropoxy) propytrimethoxysilane (KH560) and OA, silica/natural rubber (NR) and SiO2‐g‐OA/NR composites were prepared by mechanical blending in an internal mixer, and SiO2‐g‐OA was characterized by Fourier transform infrared spectroscopy, thermal gravimetric analyzer, and contact angle analyzer. The mechanical properties, abrasion resistance, curing characteristics, Payne effect, and morphology of silica/NR and SiO2‐g‐OA /NR composites were investigated using universal testing machine, Akron abrasion tester, rubber processing analyzer, and scanning electron microscope, respectively. The results showed that SiO2‐g‐OA became more hydrophobic and had better compatibility with NR. Moreover, SiO2‐g‐OA/NR had weaker Payne effect, better vulcanization performance, and more excellent mechanical properties. As the content of filler was more than 30 phr, SiO2‐g‐OA/NR had lower rolling resistance and higher wet skid resistance. Compared with silica modified by other coupling agents, SiO2‐g‐OA had the best reinforcement effect on NR.

Crosslinking behavior and enhanced mechanical properties of acrylonitrile‐butadiene rubber composites by incorporating aluminum ammonium sulfate particles

ABSTRACTThe crosslinked structure formed by the metal coordination bonding provides excellent and new properties for rubber materials. Herein, the crosslinking of acrylonitrile‐butadiene rubber (NBR) is induced by introducing aluminum ammonium sulfate (NH4Al(SO4)2·12H2O) particles. The crosslinking behavior, morphology, mechanical properties, and the Akron abrasion resistance of NBR/NH4Al(SO4)2·12H2O composites were fully explored. The results show that the three‐dimensional crosslinking structure is held together by metal–ligand coordination bonds between the nitrile group and AI(III). The coordination crosslink density exhibits a considerable increase with the addition of NH4Al(SO4)2·12H2O. Thus, the mechanical properties and abrasion resistance of the obtained composites are better than that of NBR/sulfur system. Interestingly, the elongation at break for NBR/NH4Al(SO4)2·12H2O composites is over 2000% due to the nature of coordination bonds. The abrasion volume loss decreases to 0.4 cm3 for NBR/NH4Al(SO4)2·12H2O composites with 20 phr NH4Al(SO4)2·12H2O particles as compared to 0.75 cm3 for NBR/sulfur system. The obtained NBR composites with facile preparation and excellent mechanical properties make the composites based on metal coordination bonding attractive for practical use. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019, 57, 879–886

Mechanical and tribological performance of chopped basalt fiber/acrylonitrile–butadiene rubber composites

In this study, a series of basalt fiber (BF)/acrylonitrile–butadiene rubber (NBR) composites with various BF contents were prepared and evaluated. The effects of the BF content, thermal aging, and friction condition on tribological properties of the composites were the primary focus. The tribological performances of the composites were evaluated by DIN abrasion, Akron abrasion, and high‐speed block‐on‐ring tests, respectively. The results showed that with an increase in the BF content, for the DIN and Akron abrasion tests, the wear loss increased due to insufficient interactions between the BFs and the NBR matrix, whereas for the block‐on‐ring friction, both the friction coefficient and the wear loss of the composites decreased attributed to the effect of BF on transfer film formation on the polished counterpart surface. The thermal aging enhanced the wear resistance of the composites for all three friction conditions by improving the crosslinking density of the NBR matrix. POLYM. COMPOS., 40:630–637, 2019. © 2017 Society of Plastics Engineers

Preparation of nano‐silica loaded N‐cyclohexyl‐2‐benzothiazole sulphonamide and its application in solution styrene‐butadiene rubber/butadiene rubber composites

N-cyclohexyl-2-benzothiazole sulphonamide (rubber vulcanisation accelerator CZ) was grafted onto the surface of dispersible nano-silica (DNS) to obtain silica-loaded rubber vulcanisation accelerator CZ (DNS-CZ) through in-situ surface modification. A series of as-prepared DNS-CZ samples with different CZ loadings were used as the fillers to reinforce the composites made of solution styrene-butadiene rubber (SSBR) and butadiene rubber (BR). The effect of DNS-CZ fillers on the mechanical properties of the SSBR/BR composites was investigated in relation to the scanning electron microscopic observation of the filler dispersion in the rubber matrix. It was found that the CZ is chemically bonded onto the surface of nano-silica, thereby effectively reducing the polarity of the nano-silica and enhancing its compatibility with the rubber matrix. Therefore, the SSBR/BR composites filled with DNS-CZ exhibit greatly improved mechanical properties and Akron abrasion resistance than the counterparts filled with unloaded DNS. Particularly, when the loading amount of the CZ is set as 81.10 mmol/kg, the resultant SSBR/BR/DNS-CZ composite exhibits the best mechanical properties and Akron abrasion resistance, showing promising application for green tire tread.

Effect of the structural characteristics of solution styrene–butadiene rubber on the properties of rubber composites

ABSTRACTSolution‐polymerized styrene–butadiene rubber (SSBR) has been widely used in the high‐quality tire industry, and various brands of SSBR have been synthesized. Five kinds of SSBR were selected from multiple products to investigate the effects of different brands of SSBR on the comprehensive properties. Different characterization tools, such as Fourier transform infrared spectroscopy, 1H‐NMR, and differential scanning calorimetry, were used to characterize the microstructures of the SSBRs. The results show that the microstructures of the SSBRs distinctly affected the comprehensive properties of the SSBR composites, especially the properties of the “magic triangle.” For instance, the content of trans‐1,4‐butadiene positively corresponded to the Akron abrasion for the SSBR composites with different brands, and cis‐1,4‐butadiene could partly replace the influence of vinyl when the content of trans‐1,4‐butadiene was small. SSBR 2564S, SSBR 4526‐2, and SSBR 2535E were selected because of the excellent magic‐triangle properties. They were used to investigate the effects of different brands of SSBR with different ratios of natural rubber (NR) to SSBR on the comprehensive properties of the NR–SSBR rubber blend composites. The results indicate that the properties of magic triangle were distinctly enhanced. However, there was an optimized content of SSBR to enhance the wear resistance (≤15 phr). For SSBR 4526‐2, the Payne effect was negatively correlated to the content of SSBR, whereas for SSBR 2564S and SSBR 2535E, the Payne effect was positively correlated to the content of SSBR. On the basis of these results, the SSBR 2564S seemed to exhibit the best comprehensive properties to prepare a tire tread tailored for high‐performance tires. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45749.

碳纤维对氯丁橡胶性能的影响

以氯丁橡胶(CR)作为基料，碳纤维作为填充物，研究5 mm碳纤维(CF)加入氯丁橡胶的力学性能、老化性能和阿克隆磨耗性能的变化。在氯丁橡胶母炼胶(CR 100份，ZnO 5份，MgO 4份，SA 1份，DM 0.5份，NA-22 2份)基础上分别填充不同量的CF (0，5，10，15，20，25份)制备复合橡胶材料，并对此材料进行力学、老化和磨耗性能的测试。结果表明CF对CR的性能具有较大的影响，随着碳纤维的加入橡胶的邵氏A硬度、300%定伸应力和撕裂强度提高，尤其是复合材料具有优异的耐热老化性能，硬度、拉伸强度、撕裂强度、定伸应力均增加。而阿克隆磨耗性能随碳纤维量(5~25份)的从增加呈下降趋势。 The effect of 5 mm carbon fibers (CF) on the mechanical and hot-oxygen aging properties, and Akron abrasion performance of chloroprene rubber (CR) has been studied in this paper. Rubber composites were prepared with CF varying from 0, 5, 10, 15, 20, and 25 phr based on the rubber blend of CR (CR 100 phr, ZnO 5 phr, MgO 4 phr, SA 1 phr, DM 0.5 phr, NA-22 2 phr). Their properties including physical and mechanical strength, thermal aging performance and akron abrasion loss were tested. The results show that CF has great effect on the properties of CR. With the addition of CF, the Shore A hardness, 300% modulus and tear strength increase. Especially, rubber composites with CF have good thermal aging resistance, hardness, tensile strength, tear strength and modulus increase. Akron abrasion performance shows a downward trend with the content of CF varying from 5 to 25 phr.

SILICA-REINFORCED EPOXIDIZED NATURAL RUBBER TIRE TREADS — PERFORMANCE AND DURABILITY

ABSTRACTConcerns regarding climate change and public health have compelled governments to reduce the environmental impact of transport. Many countries are introducing tire labeling and legislation targeting rolling resistance, wet grip, and noise. The proposed U.S. tire label also includes wear performance. Implementation of tire labeling is enabling buyers to choose better tires. The tire industry is responding to these demands and is developing the next generation of green tires. Current passenger tire tread technology is primarily petroleum based; however, the long-term availability of fossil-fuel supplies is limited. Thus a further step to minimize the environmental impact and carbon footprint of tires over their life cycle is to use sustainable materials not derived from fossil-fuels. Sumitomo Rubber Industries used epoxidized natural rubber (ENR) reinforced with silica in their route to a greener fossil-fuel free tire (the ENASAVE 100). At 25 mol% epoxidation, ENR has a glass transition temperature (Tg) most suitable for tread applications. Silica-filled ENR-25 tread compounds deliver lower rolling resistance, hence reduced fuel consumption, and enhanced wet and ice traction compared with benchmark premium passenger or truck treads. Optimization of wear performance to extend product durability is a current focus of research. However, correlation between laboratory abrasion and on-the-road tire wear is notoriously poor. The Tun Abdul Razak Research Centre (TARRC) have used light microscopy and transmission electron microscopy (TEM) to ascertain a mechanistic insight into tread wear, using results from wear studies on-the-road and laboratory abrasion. The results indicate that the mechanism of on-the-road tire wear differs from that of in-laboratory Akron abrasion tests.

Effects of the Synergy of Hardness and Resilience on the Akron Abrasion Properties of SBR Vulcanizates

The hardness (H) and resilience (R) of rubber vulcanizates were combined together in this paper, named as hardness–resilience product (H4R), and its relationship with the Akron abrasion loss was investigated using various styrene-butadiene rubber (SBR) vulcanizates possessing specific hardness and resilience characteristics as samples. For the unfilled SBR vulcanizates with different chain microstructure, possessing high elastic resilience and low hardness, the results showed that their Akron abrasion loss had a good linear relationship with the log(H4100R). This linear relationship also occurred when these SBRs were filled with 50 phr carbon black. For two particular types of SBR, after being filled with different fractions of carbon black and aged for different times, all their Akron abrasion losses (including unaged, aged for 24 h, and aged for 48 h) also had a good linear relationship with the log(H4100R). However, this linear relationship weakened for one of the SBRs after being aged for 48 h. In the high H4R region (the carbon black fractions being 60 and 70 phr), the data obviously deviated from the fitting curve due to the high hardness of the aged vulcanizates. However, after being filled with 50 phr of various kinds of carbon blacks, the relationships between abrasion loss and log(H4100R) were also approximately linear, with the correlation coefficient of the fitting curves being 0.99966 and 0.99878, respectively, for the two types of SBR.

Investigations on the Evolution of Akron Abrasion Process of SBR Vulcanizates

The Akron abrasion processes of two different kinds of SBR (1502 and T2000R) were studies in detail in this paper. The whole Akron abrasion process (1.61 km) was divided equally into six stages, and the abrasion loss at every stage was measured. The crosslink density and abrasion pattern of every abrasion stage were investigated respectively by Nuclear Magnetic Resonance Crosslink-density Spectrometry (NMR-CDS) and optical microscopy. The effects of hot-air aging and carbon black fraction on the abrasion processes and abrasion resistance are also discussed. For both unfilled SBR1502 and SBRT2000R, it was found that the trend in the plot of abrasion loss against stage number was similar to each other. Their abrasion loss at different stages was different, and it had a maximum value at the third stage. The crosslink density decreased as the number of revolutions increased, while it increased sharply at 6000 revolutions due to the abraded surface being torn off. The microscopic studies showed that the abrasion began at 100 revolutions, and the coarse Schallamach abrasion pattern formed at 1000 revolutions. The ridges here were more or less across the circumference of the specimen. For filled vulcanizates, the abrasion resistance improved as the fraction of carbon black increased. The trend in abrasion loss plot was similar to that of the unfilled samples when the content of carbon black was lower than 30 phr. However, only a slight variation was observed in the abrasion loss at different stages when the content of carbon black was greater than 30 phr.

Prepared hydrogenated nitrile rubber (HNBR)/organo–montmorillonite nanocomposites by the melt intercalation method

AbstractThe polymer, Hydrogenated Nitrile‐Butadiene Rubber (HNBR) was melt compounded with organophilic montmorillonite (OMMT). The dispersion of the OMMT in the HNBR matrix was characterized by X‐ray diffraction (XRD), which indicated that at the temperature of 100°C, the organoclay belong to the exfoliated and interlayer structure. The effect of sulfur on the dispersion of OMMT in the polymer matrix was also studied. The vulcanization changed the dispersion of OMMT in polymer matrix greatly and the basal spacing of clay layers is decreased after vulcanization. The mechanical properties, Akron abrasion and the crude oil medium aging‐resistant of HNBR nanocomposites were examined as a function of the OMMT content in the matrix of polymer. The results of the test show remarkable improvement in tensile strength, tear strength, aging‐resistant, and hardness of HNBR nanocomposites than that of unfilled HNBR. It is obvious that the 10 phr of OMMT filled nanocomposites have the best mechanical properties. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010