Moisture Effects on TESPD-Silica/CB/SBR Compounds

2005 ◽  
Vol 78 (1) ◽  
pp. 84-104 ◽  
Author(s):  
Kwang-Jea Kim ◽  
John VanderKooi

Abstract Moisture was treated on a silica surface and it was added into bis(triethoxysilylpropyl)disulfide (TESPD)/carbon black (CB)/S-SBR compound and mixed in an internal mixer. The effects of moisture were investigated with respect to the temperature rise during mixing, processability, cure characteristics, and mechanical properties and two-pass (2P) mixings were compared with conventional three-pass (3P) mixings. Addition of the moisture treated silica into the compound lowered the heat generation during mixing, lowered the drop temperature, decreased the scorch time, lowered the heat build up, lowered the tanδ (E″/E′), increased the Mooney viscosity, increased the torque rise (MH-ML), increased the elongation modulus, increased the blow out time, and increased the deformation%. The properties of each compound were gradually increased with the level of moisture and the 2P mixing procedure generated less heat during mixing and exhibited better mechanical properties than the 3P mixing one. The addition of water molecules improved the silane reaction with silica surface via improved hydrolysis and resulted in an increased level of cross-linking. It also seemed hydrolyzes the benzothiazolesulfenamide accelerator and resulted in a faster scorch and an increased cure rate.

2017 ◽  
Vol 751 ◽  
pp. 332-336 ◽  
Author(s):  
Sarawut Prasertsri ◽  
Sansanee Srichan

This research aimed to investigate the possibility of pyrolytic carbon black (PCB) used as filler in natural rubber (NR) and its effect on Mooney viscosity, cure characteristics and mechanical properties compared with commercial carbon black (N774). The results revealed that Mooney viscosity, stiffness and heat build-up tended to increase with increasing both PCB and N774 loading, whereas elongation at break decreased. However, the maximum tensile and tear strengths appeared at the optimum filler loading for both PCB and N774. At similar filler content, PCB-filled NR compounds have higher cure time, heat build-up and thermal resistance. Nevertheless, they exhibited lower Mooney viscosity and mechanical properties compared to N774-filled NR. Finally, it can be concluded that PCB could be utilized as filler in NR compound to act as semi-reinforcing filler and was classified as a filler to reduce costs.


2017 ◽  
Vol 266 ◽  
pp. 172-176
Author(s):  
Pattarawadee Maijan ◽  
Nitinart Saetung ◽  
Wisut Kaewsakul

Mixing behaviors of the compounds filled with different reinforcing fillers were studied in correlation with compound and vulcanizate properties. Four filler systems were used including: 1) silica plus small amount of silane coupling agent; 2) carbon black; 3) pre-modified silica; and 4) silica+silane-carbon black mixed one. The results have shown that silica provides longer optimum cure time and shorter cure rate than carbon black due to accelerator adsorption on silica surface. In addition, owing to highly polar nature on silica surface the silica-based compounds show rather high viscosity, attributed to stronger filler-filler interaction as can be confirmed by Payne effect and reinforcement index. However, the commercial surface treatment or pre-modified form of silica shows superior properties than in-situ modification of silica by silane during mixing, while it gives comparable properties to carbon black-based compound. Tensile properties of vulcanizates show a good correlation with the basic properties of their compounds.


2018 ◽  
Vol 91 (2) ◽  
pp. 492-508 ◽  
Author(s):  
L. M. Polgar ◽  
J. Keizer ◽  
R. Blom ◽  
B. Niemeijer ◽  
T. de With ◽  
...  

ABSTRACT It is demonstrated that the concept of thermoreversible cross-linking of functionalized maleic anhydride grafted ethylene–propylene (EPM-g-MA) rubber using Diels–Alder chemistry is limited neither to laboratory scale using a solvent route nor to gum rubber. The use of an internal mixer is the first step toward an industrial process, since it greatly reduces the processing time and allows for a solventless process for the furan-functionalization and subsequent bismaleimide cross-linking of EPM rubber. Practical rubber compounds were prepared by mixing thermoreversibly cross-linked EPM with carbon black and mineral oil in the same batch mixer. This resulted in reinforcement of the rubber without affecting the thermoreversible character of the cross-linking. The pendant furan groups of the (non)cross-linked EPM-g-furan interact with the carbon black filler. Finally, crystalline EPM rubber compounds were prepared, which show excellent material properties and property retention over multiple reprocessing cycles.


RSC Advances ◽  
2018 ◽  
Vol 8 (19) ◽  
pp. 10573-10581 ◽  
Author(s):  
Laiyun Wei ◽  
Xuan Fu ◽  
Mingchao Luo ◽  
Zhengtian Xie ◽  
Cheng Huang ◽  
...  

Graphene oxide (GO) and carbon nanotube (CNT) hybrid fillers were used to replace partial carbon black (CB), and GO/CNT/CB/NR composites were prepared with excellent crack growth resistance, low heat build-up and superior mechanical properties.


1982 ◽  
Vol 55 (5) ◽  
pp. 1328-1340 ◽  
Author(s):  
L. F. Ramos-DeValle ◽  
R. R. Ramírez

Abstract An experimental study of the mixing and final mechanical properties of blends of guayule rubber with polyolefins was carried out. It was found that (1) variation in total mixing time during blend preparation produced only minor differences in maximum tensile properties; (2) tensile properties of the blends approach those of the plastic at GR concentrations of 50% and lower, those of the rubber at GR concentrations of 70% and higher; (3) tensile properties of partially crosslinked blends improve if the addition of DCP is effected after partial mixing of the pure homopolymers; (4) the partial cross-linking of the blend exerts a strong beneficial influence on the mechanical properties; (5) the addition of carbon black exerts little influence on the mechanical properties of the blend. It can be suggested that, at 60% GR, both polymers (GR and HDPE) show the same tendency to form the continuous or dominant phase. Above 60%, the rubber tends to be the dominant phase, and below 60% the plastic tends to be the dominant phase. The mechanical properties of partially crosslinked GR-HDPE blends are comparable with those of similar commercially available products. This suggests a further alternative in the commercialization of natural guayule rubber, namely, thermoplastic rubbers.


2021 ◽  
Vol 30 ◽  
pp. 263498332110054
Author(s):  
Rungsima Chollakup ◽  
Supitta Suethao ◽  
Potjanart Suwanruji ◽  
Jirachaya Boonyarit ◽  
Wirasak Smitthipong

The effects of carbon black on the properties of rubber composites were studied in order to explore their value in producing low rolling resistance truck tires. Carbon black with different grades, N330 (coarser grade of 26–30 nm) and N220 (finer grade of 20–25 nm), was used as a reinforcing agent of natural rubber. The effects of different ratios of carbon black N330 at 40, 45, 50 and 55 parts per hundred rubber (phr) and N220 at 30, 35, 40 and 50 phr were investigated. Rubber composites with N220 had greater rubber/carbon black interaction than those with N330. The Mooney viscosity of rubber composite increased when the carbon black ratio increased. After vulcanisation of rubber, the samples were characterised by dynamic mechanical analysis, tensile strength and heat build-up. The results showed that the strength of rubber composites increased with increasing carbon black ratios. Interestingly, at the same bound rubber level, rubber composites with N220 presented lower dissipation energy, heat build-up and better mechanical properties than those with N330. This study indicated that reinforcement with an optimum amount of carbon black N220 would improve several desirable characteristics of rubber composites when used in low rolling resistance truck tires.


Polymers ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 103
Author(s):  
Can Sheng ◽  
Gai Wu ◽  
Xiang Sun ◽  
Sheng Liu

In spite of a high market share of plastic IC packaging, there are still reliability issues, especially for the effects of moisture. The mechanism between moisture and epoxy polymer is still obscure. A multi-step cross-linking approach was used to mimic the cross-linking process between the DGEBA resin and JEFFAMINE®-D230 agent. Based on the molecular dynamics method, the thermo-mechanical properties and microstructure of epoxy polymer were analyzed. In this paper, the degree of cross-linking ranged from 0% to 85.4% and the moisture concentration ranged from 0 wt.% to 12 wt.%. The hydrogen bonds were investigated in the moisture invaded epoxy polymer. Although most of the hydrogen bonds were related to water molecules, the hydrogen bonds between the inside of epoxy polymer were reduced only a little as the concentration of moisture increased. The diffusion coefficient of the water molecules was found to increase with the increase of moisture concentration. When the moisture concentration was larger than 12 wt.% or smaller than 1.6 wt.%, the diffusion coefficient was less affected by the epoxy polymer. In addition, the free volume and the thermal conductivity of the epoxy polymer were considered. It was found that the moisture could increase the thermal conductivity from 0.24 to 0.31 W/m/K, identifying a coupling relationship between moisture and thermal properties. Finally, the mechanical properties of epoxy polymer were analyzed by uniaxial tensile simulation. The COMPASS and DREIDING force fields were used during the uniaxial tensile simulation. A better result was achieved from the DREIDING force field compared with the experiment. The degree of cross-linking was positively correlated with mechanical properties. For the system with the largest degree of cross-linking of 85.4%, the Young’s modulus was 2.134 ± 0.522 GPa and the yield strength was 0.081 ± 0.01 GPa. There were both plasticizing and anti-plasticizing effects when the water molecules entered the epoxy polymer. Both the Young’s moduli and yield strength varied in a large range from 1.38 to 2.344 GPa and from 0.062 to 0.128 GPa, respectively.


BioResources ◽  
2020 ◽  
Vol 15 (3) ◽  
pp. 6045-6060
Author(s):  
Zafirah Zainal Abidin ◽  
Siti Nur Liyana Mamauod ◽  
Siti Salina Sarkawi ◽  
Nurshamimi Shahirah Binti Saimi

This research aimed to elucidate the effect of black and non-black filler systems on the cure characteristics and mechanical properties of butyl reclaimed rubber (BRR). In this study, BRR800 was the BRR investigated. Since reclaimed rubber is not entirely 100% rubber, actually being a mixture of rubber, carbon black, oil, zinc oxide, stearic acid and other compounding ingredients used in the original compounds, the reclaimed rubber content in each system was fixed at 161 parts per hundred (pphr). Each mixture was mixed using a two-roll mill. The fillers used in this study were carbon black and calcium carbonate. The Mooney viscosity, cure characteristics, crosslink density, and mechanical properties, such as hardness, abrasion resistance, compression set, tear strength, rebound resilience, and the tensile properties of the vulcanizates were investigated. The results showed that the Mooney viscosity of BRR800 filled with carbon black was increased effectively and had a faster curing time and higher crosslink density than BRR filled with calcium carbonate. In addition, except for compression set and elongation at break, the mechanical properties of BRR800 with a black filler system were higher than those of BRR800 with a non-black filler system.


2017 ◽  
Vol 44 (3) ◽  
pp. 13-18
Author(s):  
A.R. Mukhtarov ◽  
A.M. Mokhnatkin ◽  
V.P. Dorozhkin ◽  
E.G. Mokhnatkina ◽  
V.E. Muradyan ◽  
...  

The processing and mechanical properties of green and vulcanised breaker rubbers based on natural rubbers containing single-wall carbon nanotubes (SCNTs) were studied. SCNTs were treated and introduced into a rubber mix in a composite containing carbon black (88.24%), SCNTs (9.8%), and SKI-3 polyisoprene rubber in solution (1.96%). The presence of –COOH groups on the surface of SCNTs after treatment was confirmed by IR spectroscopy. Increase in the content of SCNTs in the breaker rubber mix to 0.15 or 0.2% leads to an increase in cohesion strength up to 1.6-fold; the Mooney viscosity also increases, and there is an improvement in the vulcanisation properties. Changes in the Payne effect of rubbers containing SCNTs indicate an improvement in the interaction between the carbon black particles. Small amounts of SCNTs ensure a reduction in tg δ at 60°C, and increases in tear strength and in adhesion to metal cord. However, wear resistance deteriorates. The possibility of replacing 30 parts natural rubber with SKI-3 in the presence of SCNTs is shown.


2016 ◽  
Vol 48 (8) ◽  
pp. 659-676 ◽  
Author(s):  
Young Seok Lee ◽  
Seong Hwan Park ◽  
Jong Cheol Lee ◽  
KiRyong Ha

Acrylonitrile butadiene rubber (NBR) is widely used in seal applications due to its excellent oil resistance. In this article, carbon black-filled NBR composites, which differed in their acrylonitrile (ACN) and butadiene content ratios, were prepared and their curing characteristics and mechanical properties were investigated. Curing characteristics were investigated by measuring chemical kinetics and onset temperature of cross-linking reaction. Cross-linking density was measured by the volume swelling test. Mechanical properties, oil resistance, and compression set (CS) tests were also conducted. From these results, it was found that the microstructure in NBR polymer is closely connected to the curing characteristics and mechanical properties of the composite. On increasing the ACN content, Shore A hardness, tensile strength at break, elongation at break, oil resistance, and CS were raised, while, on the other hand cross-linking density, kinetics of cross-linking reaction, and bound rubber content were decreased.


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