Physical Adsorption of Polymers on Disordered Filler Surfaces

1995 ◽  
Vol 68 (1) ◽  
pp. 26-36 ◽  
Author(s):  
Gert Heinrich ◽  
Thomas A. Vilgis
Keyword(s):  
Carbon Black ◽  
Physical Adsorption ◽  
Polymer Networks ◽  
Particle Surface ◽  
Configurational Entropy ◽  
Polymer Chains ◽  
Filled Polymer ◽  
Fractal Surfaces ◽  
The Difference ◽  
Surface Dimension

Abstract The problem of polymer adsorption on carbon black surfaces is considered within the concept of disorder-induced localization of polymer chains on disordered or fractal surfaces. The model describes how physical adsorption properties are enhanced compared to the adsorption on a flat surface. The difference is based on the configurational entropy which is less restricted in the disordered case than in the flat case. In fact, the surface of the carbon black particles is disordered over certain length scales and several experimental techniques have shown that the particle surface is fractal. This fractal nature can be quantified by the surface spectral density and the noninteger fractal surface dimension. As a main consequence, the coupling between filler and polymer is caused by entanglements formed between tightly adsorbed bound rubber on the filler surface and the bulk rubber far removed from the surface. The corresponding density of couples is estimated for several filled polymer networks using tensile test results. The stress-strain relations used are based on a new rigorous molecular-statistical model of filled polymer networks with quenched topology that includes the entanglements within the mobile rubber phase (configurational tube-model).

The effect of blob size in polymer networks on nanoparticle-mediated adhesion of hydrogels

Soft Matter ◽  
2019 ◽  
Vol 15 (48) ◽  
pp. 9942-9948
Author(s):  
Sohyun Kim ◽  
Tae Hui Kang ◽  
Gi-Ra Yi
Keyword(s):  
Mesoporous Silica ◽  
Silica Nanoparticles ◽  
Pore Diameter ◽  
Physical Adsorption ◽  
Mesoporous Silica Nanoparticles ◽  
Polymer Networks ◽  
Mesh Size ◽  
Adhesion Energy ◽  
Polymer Chains

Mesoporous silica nanoparticles can be used as an adhesive for hydrogels due to their physical adsorption to polymer chains, in which adhesion energy can be affected by the ratio of mesh size and pore diameter.

scholarly journals Nature of Carbon Black Reinforcement of Rubber: Perspective on the Original Polymer Nanocomposite

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 538
Author(s):  
Christopher G. Robertson ◽  
Ned J. Hardman
Keyword(s):  
Carbon Black ◽  
Physical Adsorption ◽  
Particle Morphology ◽  
Polymer Nanocomposite ◽  
Polymer Particle ◽  
Polymer Chains ◽  
Filled Rubber ◽  
Rubber Compounds ◽  
Filler Reinforcement ◽  
Industrial Use

Adding carbon black (CB) particles to elastomeric polymers is essential to the successful industrial use of rubber in many applications, and the mechanical reinforcing effect of CB in rubber has been studied for nearly 100 years. Despite these many decades of investigations, the origin of stiffness enhancement of elastomers from incorporating nanometer-scale CB particles is still debated. It is not universally accepted whether the interactions between polymer chains and CB surfaces are purely physical adsorption or whether some polymer–particle chemical bonds are also introduced in the process of mixing and curing the CB-filled rubber compounds. We review key experimental observations of rubber reinforced with CB, including the finding that heat treatment of CB can greatly reduce the filler reinforcement effect in rubber. The details of the particle morphology and surface chemistry are described to give insights into the nature of the CB–elastomer interfaces. This is followed by a discussion of rubber processing effects, the influence of CB on crosslinking, and various chemical modification approaches that have been employed to improve polymer–filler interactions and reinforcement. Finally, we contrast various models that have been proposed for rationalizing the CB reinforcement of elastomers.

scholarly journals The Physical Adsorption of Gelatinized Starch with Tannic Acid Decreases the Inhibitory Activity of the Polyphenol against α-Amylase

Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1233
Author(s):  
Yueyi Wang ◽  
Shuangshuang Li ◽  
Fangting Bai ◽  
Junwei Cao ◽  
Lijun Sun
Keyword(s):  
Enzyme Inhibition ◽  
Tannic Acid ◽  
Inhibitory Activity ◽  
Adsorption Property ◽  
Physical Adsorption ◽  
Enzyme Active Site ◽  
Opposite Trend ◽  
Gelatinized Starch ◽  
The Difference

The effects of mixing orders of tannic acid (TA), starch, and α-amylase on the enzyme inhibition of TA were studied, including mixing TA with α-amylase before starch addition (order 1), mixing TA with pre-gelatinized starch before α-amylase addition (order 2) and co-gelatinizing TA with starch before α-amylase addition (order 3). It was found that the enzyme inhibition was always highest for order 1 because TA could bind with the enzyme active site thoroughly before digestion occurred. Both order 2 and 3 reduced α-amylase inhibition through decreasing binding of TA with the enzyme, which resulted from the non-covalent physical adsorption of TA with gelatinized starch. Interestingly, at low TA concentration, α-amylase inhibition for order 2 was higher than order 3, while at high TA concentration, the inhibition was shown with the opposite trend, which arose from the difference in the adsorption property between the pre-gelatinized and co-gelatinized starch at the corresponding TA concentrations. Moreover, both the crystalline structures and apparent morphology of starch were not significantly altered by TA addition for order 2 and 3. Conclusively, although a polyphenol has an acceptable inhibitory activity in vitro, the actual effect may not reach the expected one when taking processing procedures into account.

Adsorption Characteristics of Superplasticizer with Waste Plexiglas (WPS) onto Cement Particle Surface

2011 ◽  
Vol 328-330 ◽  
pp. 547-550
Author(s):  
Gang Zheng ◽  
Ru Min Wang ◽  
Gao Yang Zhao ◽  
Zhong Yu
Keyword(s):  
Physical Adsorption ◽  
Particle Surface ◽  
Radical Copolymerization ◽  
Cement Particle ◽  
Free Radical Copolymerization ◽  
Ζ Potential ◽  
Adsorption Characteristics ◽  
Adsorbed Quantity ◽  
Uv Visible ◽  
Repulsive Forces

In this study, by using UV-visible adsorption spectrophotometer, ζ-potential analyzer and X-ray photo spectroscopy, the adsorption characteristics and surface electrochemical properties of WPS were studied in comparison with traditional naphthalene sulfonated formaldehyde condensates (FDN) whose dispersion ability mainly depends on electrostatic repulsive forces. WPS was prepared through free radical copolymerization in self-Single screw reactive extruder and synthesized from waste plexiglas and vinyl monomers by way of special extrusion modification. The results show that the adsorption of WPS and FDN on cement particle surface approximately conforms to Langmuir’s adsorption isotherm. The adsorption of WPS belongs to physical adsorption and its saturated adsorbed quantity was 5.38mg/g. When the dosage of WPS was 1 wt.% of cement, the thickness of the adsorption layer on the surface of cement particles was 61.2 nm. The ζ-potential of cement particle with WPS changed from positive (15 mV) to negative (-64.74mV) with its concentration increasing from 0 to 20 g/L and decreased from -65.19 to-39.82 mV (reducing by 38.9%) with its concentration of 10 g/L within 60 h.

Chemical Stress Relaxation of NR Networks Prepared in the Swollen State

1986 ◽  
Vol 59 (4) ◽  
pp. 541-550 ◽  
Author(s):  
Kyung-Do Suh ◽  
Hidetoshi Oikawa ◽  
Kenkichi Murakami
Keyword(s):  
Stress Relaxation ◽  
Network Structure ◽  
Three Dimensional ◽  
Polymer Chains ◽  
Chemical Stress ◽  
Network Chain ◽  
Crosslinking Process ◽  
Dimensional Network ◽  
Chemical Relaxation ◽  
The Difference

Abstract From the experimental results of the present investigation, it is apparent that two kinds of networks which have a different three-dimensional network structure give quite different behavior of chemical stress relaxation, even if both networks have the same network chain density. The difference in three-dimensional network structure for the two kinds of rubber arises from the degree of entanglement, which changes with the concentration of the polymer chains prior to the crosslinking process. The direct cause of chemical relaxation is due to the scission of network chains by degradation, whereas the total relaxation is caused by the change of geometrical conformation of network chains. This then casts doubt on the basic concept of chemorheology which is represented by Equation 2.

scholarly journals Electrical Behaviour of a Carbon Black-Filled Polymer-Based Concrete

1996 ◽  
Vol 5 (5) ◽  
pp. 096369359600500
Author(s):  
L. Rejón ◽  
R. Flores ◽  
M. A. Ponce ◽  
V.M. Castaño
Keyword(s):  
Carbon Black ◽  
Electrical Performance ◽  
Electrical Behaviour ◽  
Filled Polymer ◽  
Carbon Black Concentration ◽  
Before And After

The electrical performance (current, I vs. voltage, V) of a novel polymer-based composite, modified with varying amounts of carbon black, was studied. Distinctive regimens of the I vs. V curves, before and after a critical carbon black concentration, were found and the feasible mechanisms for such behaviour are discussed.

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