• Elastomers and Composites
• /
• v.30 no.3
• /
• pp.207-217
• /
• 1995

The reinforcement of Inorganic filler silica treated with LBR-MDI In SBR vulcanizates were Investigated. The inorganic filler silica treated with MDI on unmodified surface and that of silica treated by MDI was retreated with LBR. The charateristics of vulcanization, physical properties, surface properites and dynamic properties were investigated after mixing those silica with SBR and unmodified silica with SBR. Rheometric studies of the vulcanization showed that S-series has fast scorch $time(t_{10})$ and an optimum cure $time(t_{90})$ in the SBR compounds. And it was turned out that SBR vulcanizates compounded with LBR treated silica was better than any other componnds in hardness, tensile strenght, 100 300% modula and elongation. We could confirm that urea bonding is formed from IR spectrum. We concluded that L-series shows the best reinforcement effect in SBR vulcanizates.

• Elastomers and Composites
• /
• v.52 no.1
• /
• pp.35-47
• /
• 2017

A comprehensive survey of the available literature showed that in the last few decades, there has been a growing interest in the use of thermoplastic vulcanizates (TPVs). TPVs are the second largest group of soft thermoplastic elastomers (TPEs) after styrene-based block copolymers, and offer a wide range of potential and proven applications, including in mechanical rubber goods, under-the-hood applications in the automotive field, industrial hose applications, electrical applications, consumer goods, and soft touch applications. Over the last two decades, TPVs have shown a strong and steady market growth (~12% per year). Commercialized TPVs are commonly based on blends of ethylene propylene diene monomer (EPDM) rubber and polypropylene (PP), and to a lesser extent on combinations of butyl or nitrile rubber with PP. EPDM/PP TPVs are characterized by finely dispersed crosslinked EPDM rubber particles (particles size varying between 0.5 and $2.0{\mu}m$) distributed in a continuous thermoplastic PP matrix. If the rubber particles of such a blend are small enough and if they are vulcanized well enough, then the properties of the blend are generally improved. This review article introduces various topics and aspects relevant to EPDM/PP TPVs. The development of TPVs, the use of various types of crosslinking systems and co-agents as crosslinking agents for PP/EPDM blends, the morphology and rheology of TPVs, and their typical end-use applications are also reviewed.

• Elastomers and Composites
• /
• v.34 no.2
• /
• pp.147-155
• /
• 1999

Waxes compounded into rubber migrate to the surface and form a protection film on the rubber surface. In general, antiozonants were used with wax to protect ozonation of rubber. Influence of wax barrier formed on the surface of a rubber vulcanizate on migration of antiozonants was studied using natural rubber (NR) vulcanizates containing various type waxes. IPPD (N-isopropyl-N'-phenyl-p-phenylenediamine), HPPD (N-l,3-dimethylbutyl-N'-phenyl-p-phenylenediamine), SBPPD (N,N'-di(sec-butyl)-p-phenylenediamine), and DMPPD (N,N'-di(1,4-dimethylpentyl)-p-phenylenediamine) were employed as antiozonants. Migration experiments were performed at constant temperatures of 60 and $80^{\circ}C$ for 10, 20, 30 days using a convection oven. The migration rates of the antiozonants in the vulcanizate without wax are faster than those in the vulcanizates containing waxes. The antiozonants migrate slower in the vulcanizate containing wax with a high molecular weight distribution than in the vulcanizate with a low one. The migration rates of DMPPD and SBPPD are faster than those of HPPD and IPPD.

• Journal of Environmental Science International
• /
• v.9 no.6
• /
• pp.511-515
• /
• 2000

The purpose of this experiment is to prepare ethylene propylene diene terpolymer(EPDM)/ acrylonitrile butadiene rubber(NBR) blend which represents good environmental resistant properties including favorable oil and ozone resistance. With incorporation of EPDM, NBR and other ingredients, the rubber and chemical additives were mixed by mechanical method such as Banbury mixer and open 2-roll mill. Then rubber vulcanizates were manufactured by hot press and mechanical properties, oil and ozone resistance of the test specimens were measured. The oil resistance and ozone resistance of EPDM and NBR, respectively, is remarkably improved by blending EPDM with NBR. The optimum results of oil and zone resistant characteristics were obtained at EPDM/NBR(=25/75 wt%) composition ratio.

• Macromolecular Research
• /
• v.8 no.6
• /
• pp.285-291
• /
• 2000

Influence of silane coupling agent, bis-(3-(triethoxisilyl)-propyl)-tetrassulfide, on cure characteristics and bound rubber content of filled styrene-butadiene rubber (SBR) compounds and on physical properties of the vulcanizates was studied. Carbon black-filled and silica-filled compounds were compared. Content of the bound rubber increased with increased content of the silane coupling agent and this trend was shown more clearly in the silica-filled compounds. Optimum cure time of the carbon black-filled compound increased with increase of the silane content, while that of the silica-filled one decreased. Cure rate of the carbon black-filled compound became slower as the silane content increased while that of the silica-filled one became faster. By increasing the silane content, the minimum torque decreased and the delta torque increased. Physical properties of the silica-filled vulcanizate were found to be improved by adding the silane coupling agent. However, for the carbon black-filled vulcanizates, the tensile strength and tear resistance decreased with increase of the silane content. The differences between the carbon black-filled and silica-filled compounds were explained by difference in the reactivities of the fillers with the silane.

• Elastomers and Composites
• /
• v.19 no.4
• /
• pp.231-242
• /
• 1984

NR vulcanizate has its unigue characteristic of cushion, silence, vibration energy absorbtion etc. By reason of the above captioned characters, The vulcanizate has been widely applied to production of auto tires, belts and engine mounts, The purpose of this study is to examine the effect of rubber-filler attachments on the various dynamic properties of the NR vulcanizates. For this study, the elastic modulus and damping values are examined by means of the (RDS) the Good Rich Flexometer. The results of this study showed as follows. The damping values of the vulcaniz ates in the elastic region showed showed strong relations the damping values and the filler characteristics. The vulvanizates filled with carbon black had higher damping values than the vulcanizates loaded with inorganic filler. The Goodrich Flexometer test showed that build up for the silica filled NR vulcanizates was higher than those for which contained other fillers.

• Elastomers and Composites
• /
• v.29 no.1
• /
• pp.18-29
• /
• 1994

The purpose of this study is to investigate reinforced effect between silica treated by coupling agents and rubber matrix under the configuration chemical bonds, and the effect of silica particles coated by organic polymers using aluminum chloride as the catalyst. In vulcanization characteristies were tested by Curastometer. The M-series vulcanizates were reached to the fastest optimum cure $time(t_{90})$ and R-series vulcanizates with the same formula had the shorted optimum cure times. Tensile characteristics measuring with a tensile tester revealed that the M-series vulcanizate was the best in the physical properties, such as tensile strength. In 100% modulus, however, the S-series vulcanizates appeared to be better than the other vulcanizates. Also, hardness showed the following order : S-series>R-series>M-series with the order of elongation R-series>M-series>S-series. In SEM test, shapes of chemical treated silicas were observed. The dispersion of filler in the SBR composite appeard uniformly. In RDS test for the dynamic characteristics, G' indicates that S-3 shows the highest value with the next order M-3>R-3, and the order of damping values are as followe: M-3>M-3>R-3.

• Elastomers and Composites
• /
• v.44 no.4
• /
• pp.397-400
• /
• 2009

Ozone caused the crack on the surface of a rubber article by oxidation of double bond at room temperature. Wax migrates to the surface of a rubber article and makes a physical barrier to prevent process of ozonation. We investigated change of molecular weight distribution of waxes in unfilled NR, SBR, and BR vulcanizates before and after aging at room temperature for 6 months. Migration and evaporation behaviors of wax in a rubber article at ambient conditions help understand a role of wax as an antidegradant and appearance contamination of a rubber article. The relative intensity distribution of n-alkanes of the NR specimen after the aging was shifted to higher molecular weight compared with the relative intensity distribution before the aging, while those of the SBR specimen before and after the aging did not show a big difference.

• Elastomers and Composites
• /
• v.41 no.3
• /
• pp.164-171
• /
• 2006

Stress softening behaviors of SBR vulcanizates reinforced with silica or carbon black were studied. Two types of SBR with different 1,2-unit contents of 18 and 60 wt% were used and three filler systems of carbon black and silica with/without silane coupling agent were employed. Stress softening behaviors of the SBR vulcanizates were varied with the SBR types as well as the filler systems. The silica-filled rubber specimens had higher residual strains than the carbon black-filled ones. The residual strains of silica-filled vulcanizates were remarkably reduced by adding a silane coupling agent. The maximum loads at 50% maximum stretch of the carbon black-filled vulcanizates were lower than those of the silica-filled ones. On the contrary, the maximum loads at 200% maximum stretch of the carbon black-filled vulcanizates were higher than those of the silica-filled ones. The maximum loads of the specimens with the 1,2-unit content of 60 wt% are higher than those with the 1,2-unit content of 18 wt% irrespective of the filler systems.

• Proceedings of the Korean Fiber Society Conference
• /
• 1996.04a
• /
• pp.5-8
• /
• 1996