Filler Aggregates and Their Effect on Reinforcement

1974 ◽  
Vol 47 (2) ◽  
pp. 411-433 ◽  
Author(s):  
A. I. Medalia
Keyword(s):  
Carbon Black ◽  
Fine Particles ◽  
High Surface ◽  
High Surface Area ◽  
Experimental Studies ◽  
Spherical Particles ◽  
Rubber Compound ◽  
Carbon Blacks ◽  
Reinforcing Fillers ◽  
Aggregate Nature

Abstract The most highly reinforcing fillers, namely carbon blacks and silicas, consist of aggregates of quasi-spherical particles fused together. In the absence of direct experimental studies with single-particle carbon blacks or silicas of high surface area, we cannot be sure if aggregated structure is essential for good reinforcement, or whether aggregation and fusion just happen to accompany the formation of fine particles at practical concentrations. In any case, there is no doubt that the aggregate nature of the filler plays a major role in determining the properties of the rubber compound. Here I would like to review what we know about filler aggregates, especially of carbon black, and suggest some mechanisms for their effects on rubber; and also indicate where our knowledge seems inadequate at the present time.

Filler-Elastomer Interactions. Part VII. Study on Bound Rubber

1993 ◽  
Vol 66 (2) ◽  
pp. 163-177 ◽  
Author(s):  
Siegfried Wolff ◽  
Meng-Jiao Wang ◽  
Ewe-Hong Tan
Keyword(s):  
Surface Area ◽  
Physical Adsorption ◽  
High Surface ◽  
High Surface Area ◽  
Interfacial Area ◽  
Filler Loading ◽  
Rubber Content ◽  
Critical Loading ◽  
Carbon Blacks ◽  
Bound Rubber

Abstract SBR compounds were filled with 17 carbon blacks covering the whole range of rubber grades and tested for bound-rubber content. It was found that the bound-rubber content of a polymer at high loadings is higher for large surface-area carbon blacks. On the other hand, the bound-rubber content per unit of interfacial area in the compound (specific bound-rubber content) decreases with increasing specific surface area and filler loading. This observation was interpreted in terms of interaggregate multiple molecular adsorption, filler agglomeration, and change of molecular weight of rubber during mixing. When the comparison was carried out at critical loading of a coherent mass, the specific bound-rubber content was found to be higher for the high-surface-area products which are characterized by high surface energies. The critical loading of coherent mass of bound rubber also shows a strong surface-area dependence, indicating that large particle carbon blacks give high critical loadings. The measurements of bound rubber at high temperatures for carbon-black-filled compounds and in an ammonia atmosphere for silica-filled compounds suggest that bound rubber is caused essentially by physical adsorption.

4374113 Production of high surface area carbon blacks

Carbon ◽  
1983 ◽  
Vol 21 (6) ◽  
pp. ii
Author(s):  
Barrie Yate ◽  
Ronald Hurst
Keyword(s):  
Surface Area ◽  
High Surface ◽  
High Surface Area ◽  
Carbon Blacks

scholarly journals Dissolution Enhancement of Gliclazide Using pH Change Approach in Presence of Twelve Stabilizers with Various Physico-Chemical Properties

2009 ◽  
Vol 12 (3) ◽  
pp. 250 ◽  
Author(s):  
Roya Talari ◽  
Ali Nokhodchi ◽  
Seyed Abolfazl Mostafavi ◽  
Jaleh Varshosaz
Keyword(s):  
Dissolution Rate ◽  
Fine Particles ◽  
High Surface ◽  
High Surface Area ◽  
Chemical Properties ◽  
High Energy ◽  
Dissolution Enhancement ◽  
Ph Change ◽  
Fast Dissolution

Purpose: The micronization using milling process to enhance dissolution rate is extremely inefficient due to a high energy input, and disruptions in the crystal lattice which can cause physical or chemical instability. Therefore, the aim of the present study is to use in situ micronization process through pH change method to produce micron-size gliclazide particles for fast dissolution hence better bioavailability. Methods: Gliclazide was recrystallized in presence of 12 different stabilizers and the effects of each stabilizer on micromeritic behaviors, morphology of microcrystals, dissolution rate and solid state of recrystallized drug particles were investigated. Results: The results showed that recrystallized samples showed faster dissolution rate than untreated gliclazide particles and the fastest dissolution rate was observed for the samples recrystallized in presence of PEG 1500. Some of the recrystallized drug samples in presence of stabilizers dissolved 100% within the first 5 min showing at least 10 times greater dissolution rate than the dissolution rate of untreated gliclazide powders. Micromeritic studies showed that in situ micronization technique via pH change method is able to produce smaller particle size with a high surface area. The results also showed that the type of stabilizer had significant impact on morphology of recrystallized drug particles. The untreated gliclazide is rod or rectangular shape, whereas the crystals produced in presence of stabilizers, depending on the type of stabilizer, were very fine particles with irregular, cubic, rectangular, granular and spherical/modular shape. The results showed that crystallization of gliclazide in presence of stabilizers reduced the crystallinity of the samples as confirmed by XRPD and DSC results. Conclusion: In situ micronization of gliclazide through pH change method can successfully be used to produce micron-sized drug particles to enhance dissolution rate.

scholarly journals Enhancing the Performance of Motive Power Lead-Acid Batteries by High Surface Area Carbon Black Additives

2019 ◽  
Vol 9 (1) ◽  
pp. 186 ◽  
Author(s):  
Hai-Yan Hu ◽  
Ning Xie ◽  
Chen Wang ◽  
Fan Wu ◽  
Ming Pan ◽  
...  
Keyword(s):  
Carbon Black ◽  
Surface Area ◽  
High Surface ◽  
High Surface Area ◽  
Cycle Life ◽  
Cycle Performance ◽  
Discharge Performance ◽  
Negative Plate ◽  
Lead Acid Batteries ◽  
Lead Acid

The effects of carbon black specific surface area and morphology were investigated by characterizing four different carbon black additives and then evaluating the effect of adding them to the negative electrode of valve-regulated lead–acid batteries for electric bikes. Low-temperature performance, larger current discharge performance, charge acceptance, cycle life and water loss of the batteries with carbon black were studied. The results show that the addition of high-performance carbon black to the negative plate of lead–acid batteries has an important effect on the cycle performance at 100% depth-of-discharge conditions and the cycle life is 86.9% longer than that of the control batteries. The excellent performance of the batteries can be attributed to the high surface area carbon black effectively inhibiting the sulfation of the negative plate surface and improving the charge acceptance of the batteries.

scholarly journals Let-down stability and screen printability of inks prepared using non-printing ink grades of carbon black pigment

2019 ◽  
Vol 48 (6) ◽  
pp. 523-532
Author(s):  
Muhammad Ali ◽  
Long Lin ◽  
Saira Faisal ◽  
Syed Rizwan Ali ◽  
Syed Imran Ali
Keyword(s):  
Carbon Black ◽  
High Surface ◽  
High Surface Area ◽  
Volatile Matter ◽  
Matter Content ◽  
Content Type ◽  
Binder Free ◽  
Series Of Experiments ◽  
The Stability ◽  
Printing Ink

Purpose This paper aims to analyse the let-down stability of the binder-free dispersion of non-printing ink grades of carbon black and to assess the screen-printability of the finished inks formulated thereof from these pigment dispersions. Design/methodology/approach Binder-free pigment dispersions that were prepared and optimised following a ladder series of experiments (reported in a separate study by the authors) were let-down with three different binders such that inks containing various amounts of a binder were prepared followed by a rheological characterisation immediately after formulation and after four weeks of storage. The screen printability of the inks that displayed considerable stability was assessed, so was the ink film integrity. Findings The pigment dispersions that were considered in the present study were generally found to be stable after let-down with different binders. This was indicated by the fact that the finished inks possessed a shear thinning viscosity profiles, after formulation and after storage, in most of the cases. Furthermore, the screen printability of the inks was also found to be good in terms of registration quality of a selected design. The structure of the ink film deposits on uncoated and binder-coated textile fabrics was also highly integrated and free from discontinuities. Originality/value Carbon blacks with very low volatile matter content and/or high surface area are generally not considered suitable for use in the formulation of printing inks. This is because of their generally poor dispersability and inability to form dispersions that remain stable over extended periods. This work, which is a part of a larger study by the authors, concerns with the stability of inks formulated from binder-free dispersions of such non-printing ink grades of carbon black. The major advantage of using such pigments in inks is that the required functionality is achieved at considerably low pigment loadings.

scholarly journals Nitrogen functionalized carbon black: A support for Pt nanoparticle catalysts with narrow size dispersion and high surface area

Carbon ◽  
2015 ◽  
Vol 81 ◽  
pp. 115-123 ◽  
Author(s):  
Suzanne S. Rich ◽  
Jonathan J. Burk ◽  
Chang Sun Kong ◽  
Cynthia D. Cooper ◽  
Daniel E. Morse ◽  
...  
Keyword(s):  
Carbon Black ◽  
Surface Area ◽  
High Surface ◽  
High Surface Area ◽  
Pt Nanoparticle ◽  
Nanoparticle Catalysts ◽  
Size Dispersion
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