Elastomer nanocomposites based on NBR/BR/nanoclay: morphology and mechanical properties

2013 ◽  
Vol 33 (2) ◽  
pp. 133-139 ◽  
Author(s):  
Shohreh Tolooei ◽  
Ghasem Naderi ◽  
Shirin Shokoohi ◽  
Sedigheh Soltani

Abstract Ternary elastomer nanocomposites based on acrylonitrile butadiene rubber (NBR), polybutadiene rubber (BR) and two types of nanoclay (Cloisite 15A and Cloisite 30B) were prepared using a laboratory scale two-roll mill. The effects of nanoclay composition on the cure characteristics, mechanical properties and morphology of NBR/BR (50/50) nanocomposite samples containing 3, 5, 7 and 10 wt% nanoclay were investigated. According to the cure characteristics both types of nanoclay caused a reduction in the scorch time and optimum cure time of the nanocomposite compound. X-ray diffraction patterns of all samples suggested the intercalation of polymer chains into the silicate layers. This was confirmed by transmission electron microscopy (TEM) micrographs. Dynamic mechanical thermal analysis (DMTA) was utilized to study the dispersion state of nanoclay within the elastomer blend matrix. The results showed the development of mechanical properties with the establishment of interactions between nanoclay and polymer chains. Antiknock and brake fluid uptake were also reduced with increasing the nanoclay content.

2013 ◽  
Vol 594-595 ◽  
pp. 735-739 ◽  
Author(s):  
Muhammad Ridhwan Jamalul Nasir ◽  
N.Z. Noimam ◽  
Hanafi Ismail ◽  
Mohd Mustafa Al Bakri Abdullah ◽  
Rosniza Hamzah

Cure characteristics and crosslink density of virgin acrylonitrile butadiene rubber/recycled acrylonitrile butadiene rubber (vNBR/rNBR) blends were studied. Three different size ranges of rNBR particles, i.e., 150 - 350 μm, 2.0-15.0 mm, and 5-10 cm were used in this study. The vNBR/rNBR blends with blend ratios of 95/5, 85/15, 75/25, 65/35, and 50/50 were prepared using a two roll-mill at room temperature. The characterization results of the blends show that scorch time, t2, of the vNBR/rNBR blends decreased with increased rNBR content as well as decreasing sizes of rNBR particles while cure time, t90of the vNBR/rNBR blends increase with increased rNBR content as well as increasing sizes of rNBR particles. Among all blend ratios, the vNBR/rNBR blends with smallest size of rNBR particles exhibit lowest minimum torque (ML) compared with the bigger particle sizes of it in vNBR/rNBR blends which resulted in more efficient processing. The maximum torque (MH) of all vNBR/rNBR blends shows the inclining trend with increased rNBR. The cross-linking density of vNBR/rNBR blends also show an increasing trend with increasing rNBR content.


2005 ◽  
Vol 21 (2) ◽  
pp. 101-115
Author(s):  
Chaoying Wan ◽  
Yong Zhang ◽  
Yin Zhu ◽  
Yinxi Zhang

Four kinds of nano-sized calcium carbonate (CaCO3) surface-modified with stearic acid, aluminate, titanate and aluminate-titanate complex coupling agents, were used to reinforce natural rubber (NR)/styrene-butadiene rubber (SBR) blends. The effects of surface modification and CaCO3 content on the cure characteristics, swelling behaviour, and mechanical properties of NR/SBR blends were studied. The surface modification of CaCO3 improved the processing and mechanical properties, and the stearic acid coated CaCO3 (SA-CaCO3) had finer dispersion and produced a better reinforcement effect than the other modified CaCO3. Furthermore, a commercial high abrasion furnace carbon black (HAF) was used for comparison. The results showed that both CaCO3 and HAF increased the cure rate, reduced the optimum cure time and improved the mechanical properties of NR/SBR blends at appropriate filler contents. The tensile strength of filled NR/SBR composites reached its maximum value when the SA-CaCO3 content was 50 phr or the HAF content was 30 phr. The modulus at 200%, tear strength, and Shore A hardness of filled NR/SBR composites all increased with increasing filler content. The CaCO3 reinforced the NR/SBR blends to some extent, though it was still not as effective as HAF.


2011 ◽  
Vol 264-265 ◽  
pp. 646-651 ◽  
Author(s):  
Wittawat Wongsorat ◽  
Nitinat Suppakarn ◽  
Kasama Jarukumjorn

Natural rubber (NR) was reinforced with three types of filler: carbon black, calcium carbonate, and sisal fiber. NR composites were prepared on a two-roll mill. Filler content was 20 phr. Mechanical properties and cure characteristics of NR composites were studied. All NR composites had higher maximum torque than NR. NR filled with carbon black showed the highest maximum torque. However, scorch time and cure time of the NR composites were not much affected by filler types. In addition, influence of fiber treatment (alkalization) on mechanical properties and cure characteristics of sisal fiber-NR composites was investigated. Alkali treated sisal fiber-NR composite exhibited higher tensile properties and hardness than untreated sisal fiber- NR composite due to improved adhesion between the fiber and NR matrix. Moreover, alkali treated sisal fiber-NR composite had superior specific modulus and strength than NR composites filled with carbon black and calcium carbonate.


2015 ◽  
Vol 815 ◽  
pp. 24-28
Author(s):  
N.R. Munirah ◽  
N.Z. Noriman ◽  
M.Z. Salihin ◽  
H. Kamarudin ◽  
M.H. Fatin ◽  
...  

The role of activated carbon (AC) in rubber compounds was investigated to better understand the reinforcing mechanism. The activated carbon filled styrene butadiene rubber vulcanizates (SBR-AC) using bamboo activated carbon as filler were prepared by using two-roll mill and cured at 160 °C. AC filler loading from 10 to 50 phr (part per hundred rubber) were used in this study. Study into the influences of filler loading on the cure characteristics, swelling behaviour and physical properties (hardness and resilience) of SBR-AC vulcanizates were carried out. It was observed that SBR-AC vulcanizates has better cure characteristics compared to the styrene butadiene rubber gum vulcanizate (SBR-GV) which is a non-filled vulcanizate. The results showed that the scorch time (ts2) decreased with increasing filler loading. The cure time (tc90) slightly decreased up to 20 phr before a rise as the filler loading increased. The minimum torque (ML) of SBR vulcanizate increased and the maximum torque (MH) decreased up to 20 phr but then increased with increasing filler loading. The cure rate index (CRI) of SBR-GV vulcanizate was higher than that of all SBR-AC vulcanizates. Up to 20 phr of filler loading, the CRI increased before a decline occurred as the filler loading increased. As expected, the hardness value of SBR-AC vulcanizates was higher compared to SBR-GV vulcanizate which has lower resilience. The hardness and crosslink density showed an increasing trend meanwhile the resilience was adversely affected by the increase in filler loading. Bamboo activated carbon showed some potential enhancement on the reinforcing and physical properties of the vulcanizates.


2017 ◽  
Vol 744 ◽  
pp. 295-299
Author(s):  
Saowaluk Boonyod ◽  
Chaiwute Vudjung

Natural rubber (NR) containing the nata de coco fiber or Bacterial cellulose (BC) was prepared by co-coagulation of BC and concentrated NR latex with CaCl2 and compounded by two roll mill. The effect of oleic acid (OA) containing in NR filled BC (NR/BC) was the important factor in this study. BC was varied from 0–25 parts per hundred parts of rubber (phr), and the Mooney viscosity, cure characteristics and mechanical properties of NR/BC with and without OA as compatiblizer was evaluated. It was found that tear strength and elongation at break of NR/BC containing OA improved. The addition of OA into NR/BC affect vulcanization properties of NR/BC masterbatch that retard the cure time of their compound. Of all BC contents investigated, the vulcanized NR/BC at 10-20 phr of BC with OA shows the optimum tear strength and the morphology of the vulcanized NR/BC is improved by the addition of OA.


2010 ◽  
Vol 123-125 ◽  
pp. 1171-1174 ◽  
Author(s):  
Wittawat Wongsorat ◽  
Nitinat Suppakarn ◽  
Kasama Jarukumjorn

Sisal fiber/natural rubber (NR) composites were prepared by the incorporation of sisal fiber into NR at various content (10, 20, 30 phr) using a two-roll mill. Natural rubber grafted with maleic anhydride (NR-g-MA) prepared in house was used to improve interfacial adhesion between sisal fiber and NR matrix. NR-g-MA contents were varied. Mechanical properties, morphologies, and cure characteristics of the composites were studied. Maximum torque, modulus at 100% strain (M100), modulus at 300% strain (M300), and hardness of the composites increased with increasing fiber content while scorch time, cure time, tensile strength, and elongation at break decreased. The addition of NR-g-MA into the composites gave a positive impact on M100, M300, tensile strength, and hardness. Moreover, increasing NR-g-MA content resulted in increased scorch time, cure time, maximum torque, M100, M300, tensile strength, and hardness of the composites. SEM micrographs of the composites revealed that the addition of NR-g-MA into the composites improved the interfacial interaction between sisal fiber and NR matrix. In addition, the compatibilized NR composites exhibited higher specific tensile strength and modulus than the carbon black/NR composites.


2010 ◽  
Vol 123-125 ◽  
pp. 55-58 ◽  
Author(s):  
Chalermpan Keawkumay ◽  
Kasama Jarukumjorn ◽  
Nitinat Suppakarn

Montmorillonite (MMT) was modified by octadecylamine (ODA) surfactant. The surfactant contents were varied, i.e. 0.5, 1.0 and 2.0 times the cation exchange capacity (CEC) of the MMT. XRD and FTIR spectra of the organoclay revealed that ODA molecules intercalated into MMT layers. The MMT-ODA was melt-mixed with natural rubber (NR) using a two roll mill. Effects of surfactant content and organoclay content on cure characteristics, mechanical properties, and morphologies of NR nanocomposites were investigated. Morphologies of the NR nanocomposites, with increasing surfactant content, revealed the exfoliated structure and the good dispersion of the organoclay in the NR matrix. These caused the enhancement of mechanical properties of the NR nanocomposites. With increasing the MMT-ODA2 content up to 5 phr, scorch time and cure time of the NR nanocomposites decreased while their tensile strength increased.


2002 ◽  
Vol 18 (2) ◽  
pp. 85-97 ◽  
Author(s):  
P.A. Nelson ◽  
S.K.N. Kutty

Cure characteristics and mechanical properties of Butadiene rubber/ reclaimed rubber blends were studied. Minimum torque, scorch time, and cure time decreased with the increase in reclaim content. Tensile strength, tear resistance, ultimate elongation, cure rate and compression set increased where as resilience and abrasion loss decreased with reclaim loading. The (maximum – minimum) torque was reduced at higher loading of reclaim. Heat build up was higher for the blends containing higher amounts of reclaimed rubber. Ageing resistance of the blends was inferior to that of the gum compounds.


2011 ◽  
Vol 17 (3) ◽  
pp. 315-321 ◽  
Author(s):  
Gordana Markovic ◽  
Vojislav Jovanovic ◽  
Suzana Samarzija-Jovanovic ◽  
Milena Marinovic-Cincovic ◽  
Jaroslava Budinski-Simendic

In this paper the curing and mechanical properties of two series of prepared blends, i.e., chlorosulphonated polyethylene (CSM)/isobutylene-co-isoprene (IIR) rubber blends and chlorosulphonated polyethylene (CSM)/chlorinated isobutylene-co-isoprene (CIIR) rubber blends were carried out. Blends were prepared using a two roll-mill at a temperature of 40-50?C. The curing was assessed by using a Monsanto Oscillating Disc Rheometer R-100. The process of vulcanization accelerated sulfur of pure rubbers and their blends was carried out in an electrically heated laboratory hydraulic press under a pressure of about 4 MPa and 160?. The stress-strain experiments were performed using tensile tester machine (Zwick 1425). Results indicate that the scorch time, ts2 and optimum cure time, tc90 increase with increasing CSM content in both blends. The values of modulus at 100% and at 300% elongation and tensile strength increases with increasing CSM content, whereas elongation at break shows a decreasing trend. The enhancement in mechanical properties was supported by data of crosslink density in these samples obtained from swelling measurement and scanning electron microscopy studies of the rubber blends fractured surfaces.


2002 ◽  
Vol 18 (4) ◽  
pp. 283-296 ◽  
Author(s):  
T.D. Sreeja ◽  
S.K.N. Kutty

The cure characteristics and mechanical properties of short nylon fiber – styrene butadiene rubber/whole tyre reclaim (SBR/WTR) composites with and without an interfacial bonding agent based on 4,4 diphenyl methane diisocyanate and polyethylene glycol (MDI/PEG) have been studied. An 80:40 blend of SBR/WTR reinforced with 20 phr of short nylon fiber has been selected and the MDI/PEG ratio has been changed from 0.67:1 to 2:1. The minimum and maximum torques increased with isocyanate concentration. The scorch time and cure time showed an initial reduction. The cure rate showed an initial improvement. Tensile strength, tear strength and abrasion resistance increased with MDI/PEG ratio, these values were higher in longitudinal direction. Resilience and compression set increased with isocyanate concentration.


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