Polymer colloids, definition

An aqueous colloidal polymeric dispersion by definition is a two-phase system comprised of a disperse phase and a dispersion medium. The disperse phase consists of spherical polymer particles, usually with an average diameter of 200-300 nm. According to their method of preparation, aqueous colloidal polymer dispersions can be divided into two categories (true) latices and pseudolatices. True latices are prepared by controlled polymerization of emulsified monomer droplets in aqueous solutions, whereas pseudolatices are prepared starting from already polymerized macromolecules using different emulsification techniques. 

Whether there is currently a nanotechnology is a question of definition. If one asks whether there are (or are soon likely to be) commercial electronic fluidic, photonic, or mechanical devices with critical lateral dimensions less than 20 nm, the answer is no, although there may be in 10 to 20 years. There is, however, a range of important technologies—especially involving colloids, emulsions, polymers, ceramic and semiconductor particles, and metallic alloys—that currently exist. But there is no question that the field of nanoscience already exists. 

The humic/organic matter coatings of different solid phases (i. e., SPm /SP0M), such as soils, sediments, suspended solids, colloids, and biocolloids/biosolids, interact with organic pollutants in aqueous systems in various ways. Adsorption is an important interaction mode. The reversibility and/or irreversibility of the adsorption processes is of major importance. The question whether the bound residues of pollutants are to be considered definitely inactivated has been the focus of extensive research. This question was posed as follows. Have the adsorbed pollutants become common components incorporated into the humic polymer coating of solid phases (i. e., being absorbed), or are they only momentarily inactivated in reversibly bound forms thus representing a possible source of pollution by a time-delayed release of toxic units ... 

In summary, this case study demonstrates that adsorption of non-ionic surfactants, an interesting theme in its own right, exhibits not only definite characteristics belonging to the present theme, but also involves aspects of polymers and association colloids. 

Ligand-stabilized species can be described as colloids, according to the definition given above. Colloids used in polymer matrices or other stabilizing liquid media are not considered here. Continuing the principle of ligating metal particles of cluster size, only such metal particles are taken into account which exist as individuals outside the liquids in which they are produced. 

This definition of integral distribution function is common in colloid science, while in polymer science the molecular weight distributions are typically evaluated by the summation of molecular weight smaller than the current value... 

Although contemporary systems and processes may be complex, the techniques and the content of this book stUl apply. But to maximize the value of our approach, you may need to create new definitions, characterize other properties, consider additional interactions that influence complex systems, implement coimections to molecular theory and statistical mechanics, and derive appropriate relations that are amenable to reliable modeling. In the past such characterizations were commonly done in terms of macroscopic measurables, but now molecular structure is being used to describe complex systems, including alternative-energy systems, biochemicals, colloids and interfaces, electrolytes, polymers, and exotic materials. 

Starting from the definition just given, the fact is encountered that not only linear polymers, but globular also can cover a far greater field than that according to the colloidal dimensions. As this book is devoted to colloid science, we will confine ourselves therefore chiefly to macromolecules up to 10 A only in special cases some reference will be made to larger ones. 

Colloidal surface-polymer interaction, 96 Complex fluids, definition, 1 Configuration of polyelectrolytes adsorbed onto microcapsule surface, 85-94 application in on-off control of enzyme reactions, 91,93/... 

The term colloidal suspension refers to a dispersion of colloidal particles in the bulk of another phase, usually in a different aggregation state the most common use is for solid particles in a liquid medium. Regarding the definition of colloidal particles given before, it includes either macromolecules (e.g., proteins or polymers)... 

The question often arises as to whether the term soluble silica should include the low polymers such as tetramer or deciimer. which are classed as oligomers. It becomes a matter of definition. Soluble materials have been recognized as those that pass through a dialysis membrane, whereas colloids do not but even though membranes can now be made with pores sufficiently small to separate dextrose from sucrose, we think of sucrose as being "soluble. On the other hand, sucro.se is certainly not colloidal. 

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