scholarly journals THE ORIGIN OF MARCHING MODULUS OF SILICA-FILLED TIRE TREAD COMPOUNDS

2019 ◽  
Vol 93 (2) ◽  
pp. 378-394 ◽  
Author(s):  
J. Jin ◽  
J. W. M. Noordermeer ◽  
W. K. Dierkes ◽  
A. Blume
Keyword(s):  
Coupling Agent ◽  
Coupling Reaction ◽  
Coupling Agents ◽  
Key Factors ◽  
Silane Coupling Agents ◽  
Filled Rubber ◽  
Rubber Compounds ◽  
Silane Coupling ◽  
Filler Dispersion ◽  
Distinct Maximum

ABSTRACT Silica-reinforced S-SBR/BR tire tread compounds often show characteristic vulcanization profiles that do not exhibit a distinct maximum in the cure curve nor a plateau profile within acceptable time scales (marching modulus). In such a situation, it is difficult to determine the optimum curing time, and as a consequence, the physical properties of the rubber compounds may vary. Previous studies stated that the curing behavior of silica-filled rubber compounds is related to the degree of filler dispersion, the silanization, and the filler–polymer coupling reaction, as well as to the donation of free sulfur from the silane coupling agent. Such results imply that these are the key factors for minimization of the marching modulus. Various silane coupling agents with different sulfur ranks and functionalities were mixed at varied silanization temperatures. The correlation between these factors and their effect on the marching modulus intensity (MMI) were investigated. The MMI was monitored by measuring the vulcanization rheograms using a rubber process analyzer at small (approximately 7%) and large (approximately 42%) strains to discriminate the effects of filler–filler and filler–polymer interactions on the marching modulus of the silica-filled rubber compounds. Both factors have an intricate influence on the marching modulus, determined by the degree of filler–filler interaction and the coupling agent.

EFFECTS OF SILANE AGENTS AND CURING TEMPERATURES ON VULCANIZATE STRUCTURES

2019 ◽  
Vol 93 (2) ◽  
pp. 414-428 ◽  
Author(s):  
Byungkyu Ahn ◽  
Jong-Yeop Lee ◽  
Donghyuk Kim ◽  
Il Jin Kim ◽  
Sangwook Han ◽  
...  
Keyword(s):  
Coupling Agent ◽  
Crosslink Density ◽  
Silica Surface ◽  
Coupling Reaction ◽  
Rolling Resistance ◽  
Coupling Agents ◽  
Silane Coupling Agents ◽  
Filled Rubber ◽  
Rubber Compounds ◽  
Silane Coupling

ABSTRACT Silane coupling agents are commonly used in silica-filled rubber compounds to hydrophobize the silica surface and improve filler–rubber interaction. The coupling agent bis[3-(triethoxysilyl)propyl]tetrasulfide (TESPT) is the most widely used coupling agent. The tetrasulfide is more reactive than the disulfide in bis[3-(triethoxysilyl)propyl]disulfide (TESPD) due to its low decomposition energy, resulting in more coupling reaction with rubber molecules. Meanwhile, vulcanization temperature affects chemical networks. Polysulfide is vulnerable to heat, so it can be easily broken to form shorter crosslinks. Compounds with TESPD or TESPT were vulcanized at 160 and 180 °C. In addition to the decomposition, the reactivity of the silanes was confirmed from the cure characteristics of the compounds without the curatives. TESPD could also cause a coupling reaction without the curatives such as TESPT known to release free sulfur. By analyzing vulcanizate structures, total crosslink density was separated into chemical crosslink density and filler–rubber networks. Applying TESPT or vulcanizing at 180 °C increased the filler–rubber networks, and the higher vulcanization temperature decreased the chemical crosslink density. By correlating physical properties, effects of the vulcanizate structures on performance of tread compounds were investigated. The filler–rubber interaction was dominant for wet traction and mechanical properties in tensile test. The chemical crosslink density affected rolling resistance.

COOPERATIVE EFFECTS OF EPOXIDE FUNCTIONAL GROUPS ON NATURAL RUBBER AND SILANE COUPLING AGENTS ON REINFORCING EFFICIENCY OF SILICA

2014 ◽  
Vol 87 (2) ◽  
pp. 291-310 ◽  
Author(s):  
W. Kaewsakul ◽  
K. Sahakaro ◽  
W. K. Dierkes ◽  
J. W. M. Noordermeer
Keyword(s):  
Natural Rubber ◽  
Functional Groups ◽  
Coupling Agent ◽  
Silica Content ◽  
Coupling Agents ◽  
Silane Coupling Agents ◽  
Cooperative Effects ◽  
Optimal Loading ◽  
Silane Coupling

ABSTRACT Polar functionality attached onto natural rubber has a significant impact on the reinforcing efficiency of silica. Parallel studies involving various levels of epoxidation on natural rubber (ENR) in the absence of bis-(triethoxysilylpropyl) tetrasulfide (TESPT) coupling agent, as well as a combination of ENRs with different loadings of TESPT, provide a better understanding of the various factors that influence the properties of silica-filled ENR compounds. Based on the overall properties, the best possible combination to optimize processability, to reduce filler–filler interaction, and improve vulcanization rate as well as vulcanizate properties, is to use ENR with an epoxide content in the range of 20–30 mol%, together with a small portion of TESPT, that is, 2–4 wt% relative to the silica content. This leads to a reduction of approximately 60–80% of TESPT when compared with the conventional NR compounds, where the optimal loading of TESPT was 9.0 wt% relative to the silica content.

Synthesis of Substrate-bound Seaweed-like Au Nanowires with Amino Silane Coupling Agents

2022 ◽  
Author(s):  
Jialong Yu ◽  
Weiyu Wang ◽  
Shumin Li ◽  
Beibei Yu ◽  
Hongyu Chen ◽  
...  
Keyword(s):  
Coupling Agent ◽  
Active Surface ◽  
Coupling Agents ◽  
Silane Coupling Agents ◽  
One Dimensional ◽  
Amino Silane ◽  
Silane Coupling ◽  
Dimensional Growth ◽  
Au Nanowires

Seaweed-like Au nanowires were synthesized without any nanoparticle seeds. The amino silcane coupling agent 3-aminopropyltriethoxysilane was used to form the active surface on Au substrate to facilitate one dimensional growth....

Surface Functionalization of Zirconia Nanocrystals with Silane Coupling Agent and its Dispersion Behavior in O-Phenylphenoxyethyl Acrylate

2018 ◽  
Vol 922 ◽  
pp. 20-25 ◽  
Author(s):  
Hee Seon Lee ◽  
Jeong Min Park ◽  
Kyu Hong Hwang ◽  
Hyung Mi Lim
Keyword(s):  
Coupling Agent ◽  
Silane Coupling Agent ◽  
Coupling Agents ◽  
Solvothermal Reaction ◽  
Silane Coupling Agents ◽  
Propyl Methacrylate ◽  
Silane Coupling ◽  
Ft Ir ◽  
Surface Modified ◽  
Dispersion Of Nanoparticles

Highly crystalline and dispersible zirconia, synthesized by solvothermal reaction of zirconium (IV) isopropoxide isopropanol complex in benzyl alcohol, were functionalized with silane coupling agent and dispersed with o-phenylphenoxyethyl acrylate (OPPEA). Silane coupling agents such as 3-aminopropyltriethoxysilane (APTES) of amino functional silane, decyltrimethoxysilane (DTMS) of alkyl functional silane and 3-(trimethoxysilyl) propyl methacrylate (MPS) of acrylate functional silane have been used to modify nanoparticle surfaces and obtain dispersion of nanoparticles within OPPEA. The surface modified zirconia was compared according to silane coupling agent, FT-IR and TGA demonstrated that APTES, DMTS and MPS are chemically attached to the surface of the zirconia. The MPS-zirconia is dispersed as about 5 nm sized, whereas the APTES-zirconia, DTMS-zirconia are agglomerated. The MPS-zirconia/tetrahydrofuran (THF) sol at 15wt% loading shows high transmittance of 68 % at 550 cm-1 and the 50wt% surface modified-zirconia/OPPEA sol show refractive index of 1.657.

scholarly journals Effect of Silane Coupling Agent on Modification of Areca Fiber/Natural Latex

Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4896
Author(s):  
Yiren Pan ◽  
Meng Zhang ◽  
Jian Zhang ◽  
Xiaoyao Zhu ◽  
Huiguang Bian ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Coupling Agent ◽  
Silane Coupling Agent ◽  
Natural Rubber Latex ◽  
Physical And Mechanical Properties ◽  
Coupling Agents ◽  
Silane Coupling Agents ◽  
Swelling Properties ◽  
Silane Coupling ◽  
Physical And Chemical

In this paper, the areca fiber was extracted by physical and chemical treatment, and then the areca fiber/natural latex composite was prepared by natural latex impregnation technology. In order to combine areca fiber and natural rubber latex better, three silane coupling agents with different action mechanism were selected: Si−69, KH550, and KH570 which were used to treat the areca fiber/natural latex compound. The results show that the silane coupling agent can change the surface of the fiber from hydrophilic surface to organophilic surface, making the bonding of areca fiber to natural latex more closely. At the same time, the mechanical properties, physical and mechanical properties, swelling properties, and dynamic viscoelastic properties of the tightly bonded areca fiber/nature latex composites were improved. After observing the micro-structure through a scanning electron microscope, it was found that the three silane coupling agents could effectively bind areca fiber and natural latex to enhance the performance of the composite material, of which Si−69 performed best, and the tensile strength and tear strength of the composite increased by 21.19% and 12.90% respectively.

OPTIMIZATION OF RUBBER FORMULATION FOR SILICA-REINFORCED NATURAL RUBBER COMPOUNDS

2013 ◽  
Vol 86 (2) ◽  
pp. 313-329 ◽  
Author(s):  
W. Kaewsakul ◽  
K. Sahakaro ◽  
W. K. Dierkes ◽  
J. W. M. Noordermeer
Keyword(s):  
Silane Coupling Agent ◽  
Coupling Agents ◽  
Silane Coupling Agents ◽  
Rubber Content ◽  
Rubber Compounds ◽  
Bound Rubber ◽  
Silane Coupling ◽  
Mooney Viscosity ◽  
Tan Δ ◽  
Tear Properties

ABSTRACT The rubber formulation plays a significant role in the properties of NR compounds filled with silica. In this work, the influences of various silicas, silane coupling agents, and diphenylguanidine (DPG) on the properties of compounds and vulcanizates—that is, cure characteristics, Mooney viscosity, flocculation kinetics, bound rubber content, Payne effect, tan δ at 60°C, tensile properties, and tear properties—are investigated. The results demonstrate that compound viscosity and curing behavior, as well as vulcanizate properties of the silica-filled NR, are much improved by incorporating silane coupling agents. Bis-triethoxysilylpropyltetrasulfide clearly gives better overall properties than the disulfide-based silane bis-triethoxysilylpropyldisulfide, except for scorch safety. DPG acts as a synergist to sulfenamide primary accelerators, as well as activator for the silanization reaction. Highly dispersible (HD) silicas can significantly enhance the degree of dispersion and so lead to higher filler–rubber interaction. As a consequence, the HD silicas provide better dynamic and mechanical properties for filled NR vulcanizates compared with conventional counterparts. The optimal quantities of both silane coupling agent and DPG required in the formulation are correlated to the cetyl trimethylammonium bromide specific surface area of the silicas. Furthermore, the results reveal that the silica structure as characterized by the dibutylphthalate adsorption also strongly influences the reinforcing efficiency.

scholarly journals Treatment of hollow glass bubbles with silane coupling agent. sem on hollow glass bubbles, before and after treatment with silane coupling agent

2021 ◽  
Vol 2 (2) ◽  
pp. 1-7
Author(s):  
Andrei-Ionut Perdum
Keyword(s):  
Coupling Agent ◽  
Silane Coupling Agent ◽  
Hollow Spheres ◽  
Coupling Agents ◽  
Silane Coupling Agents ◽  
Hollow Glass ◽  
Glass Spheres ◽  
Silane Coupling ◽  
Before And After ◽  
Glass Bubble

In this study will be presented, how 20 millilitres of Silane Coupling Agent, adhered on 5 grams of Hollow Glass Bubbles (HGB), how the micro bubbles are looking before and after mixing, how to filter the hollow spheres from the agent and what needed to be taken in consideration when using coupling agents in processes. This paper will show how Silane Coupling Agent (3-Aminopropyl) triethoxysilane, adhered on the Hollow Glass Bubble (HGB). It is expected to observe at HR-SEM (High- Resolution Scanning Electron Microscopy) how the Hollow Glass Bubbles looks when the Silane Coupling Agent (KH-550) is applied on the filler vs when is not. During the process will be concluded, what risks should be taken in consideration, when using Silane Coupling Agents on Hollow Glass Spheres and what important information/ steps are needed to be taken in consideration before and after coupling treatment.

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