Improved Adhesion of EPDM Sulfur Vulcanizates to RFL-Treated Fabrics

1982 ◽  
Vol 55 (5) ◽  
pp. 1516-1530 ◽  
Author(s):  
Richard W. Tomlinson

Abstract EPDM stocks containing 5-norbornene-2,3-dicarboxylic anhydride and cobalt naphthenate, when sulfur vulcanized onto RFL-treated fabrics, show a significant increase in peel adhesion properties. EPDM's containing ENB, as the termonomer, have been found to give the best results. The accelerator is an important part of the total adhesion system. Only the slower curing types are applicable, such as sulfenamides and thiazoles. Both soluble and insoluble sulfur yield equivalent adhesion properties, but the insoluble form has the advantage of producing a higher modulus stock. This adhesion system is applicable to only RFL-treated fabrics in which the latex is a styrene-butadiene-vinyl pyridine type. Reduction of compounded stock cost is possible by increased filler loadings or by the use of a skim coat technique, while still providing improved adhesion properties. Variations in both carbon black and oil levels produce corresponding changes in modulus development and curing time. These properties can be used to predict adhesion results.

2020 ◽  
Vol 39 (1) ◽  
pp. 81-90
Author(s):  
An Zhao ◽  
Xuan-Yu Shi ◽  
Shi-Hao Sun ◽  
Hai-Mo Zhang ◽  
Min Zuo ◽  
...  

2012 ◽  
Vol 19 (01) ◽  
pp. 1250003
Author(s):  
JIAN CHEN ◽  
YONGZHONG JIN ◽  
JINGYU ZHANG ◽  
YAFENG WU ◽  
CHUNCAI MENG

Bound rubber in carbon black (CB) filled rubber (natural rubber (NR) and styrene–butadiene rubber (SBS)) was prepared by the solvent method. The nanomorphology of CB and rubber/CB soluble rubber was observed by atomic force microscope. The results show that high-structure CB DZ13 has a "grape cluster" structure which consists of many original particles with the grain size of about 30–50 nm. Graphitizing process of CB decreases the amount of bound rubber. The NR/DZ13 soluble rubber with island–rim structure has been obtained, where the islands are DZ13 particles and the rims around the islands are occupied by NR film. But when the graphitized DZ13 particles were used as fillers of rubber, we have only observed that some graphitized DZ13 particles were deposited on the surface of the globular-like NR molecular chains, instead of the spreading of NR molecular chains along the surface of DZ13 particles, indicating that graphitized DZ13 has lower chemical activity than ungraphitized DZ13. Especially, we have already observed an interesting unusual bound rubber phenomenon, the blocked "bracelet" structure with the diameter of about 600 nm in which CB particles were blocked in ring-shaped SBS monomer.


2008 ◽  
Vol 35 (5) ◽  
pp. 454-460 ◽  
Author(s):  
Krzysztof Zieliński

This article describes the effect of heat aging and styrene–butadiene–styrene (SBS) content in bitumen on the adhesion properties of mastics (bitumen-filler mix) to concrete and steel substrates. Test results showed that the adhesion strength of bituminous mastics to concrete and steel substrates decreased as the SBS content increased. Bitumen types modified with 9%–12% of SBS, commonly used in waterproofing materials, showed an approximately three times weaker bond with concrete and steel substrates than the nonmodified equivalents. Results also showed that after heat aging, the adhesion strength of the nonmodified bitumen was always higher than that of the unheated bitumen modified with 9%–12% of SBS.


Author(s):  
Ruofan Liu ◽  
Erol Sancaktar

Payne and Mullins effects are widely observed in reinforced rubber materials. The mechanisms by which these two effects work are not fully understood. Several models have been proposed, including molecular slippage model, bond rupture model, and filler rupture model. In this study, two different compounds of styrene–butadiene rubber were prepared using carbon black and silica as reinforcement fillers, respectively, and subjected to cyclic fatigue process. Tensile, creep, and relaxation tests were performed on fatigued samples to assess the residual stress–strain behavior by comparing with the results from similar tests using pristine (no fatigue) samples. When the tensile stiffness behavior of fatigued specimens was evaluated, we noted that the stiffness versus strain behavior which exhibited a monotonic decreasing–increasing behavior with the pristine specimens changed to what we call “dual-stiffness” condition, where the specimens went through a first (low) turning point as with the pristine samples, but then dropped off of a peak to go through a second softening stage, similar to the first softening stage of the pristine material. We believe that such spiking (dual) stiffness behavior characterized by a “Peak” point represents a combination of both Payne and the Mullins effects active during fatigue loading. We conclude that molecular slippage and bond rupture are the main factors affecting the physical properties of carbon black-filled compounds, while breakage and recombination of the filler are the key mechanisms affecting the silica-filled compounds during the fatigue process.


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