Aggregates branched

A very widespread issue in polymer production is the existence of nano-, micro-, and macroscopic particulates. In some cases, these particulates are integral to the process, such as bacteria in bioreactors, cell fragments in bioextraction, or latex particles in emulsion polymerization. In most cases, however, the particulates are unwanted and can be detrimental both to the product and the reactors. Such particulates include physical aggregates, branched and cross-linked microgels, microcrystals, impurity particles, and macroscopic coagula. This topic is covered in depth in Section 14.3. 

The oil furnace process involves a liquid hydrocarbon, usually a heavy petroleum oil, which is injected, sprayed, and mixed with preheated air and natural gas in a reactor. Part of the hydrocarbon is burned to maintain the reaction temperature ranges of 1,450 to 1,800 °C and the remainder is converted to carbon black. This process has a lower residence time and yields a narrower distribution of carbon black aggregate sizes, higher surface activity, and open aggregates (branched or grapelike (bulky)). 

A main problem concerning the solid state electronic properties of PPPs is its tendency to form aggregates. One synthetic strategy for overcoming this problem is the transition from linear, one-dimensional systems to branched or dendritic, two-dimensional ones. 

In the case of amphiphilic molecules, characterized by the coexistence of spatially separated apolar (alkyl chains) and polar moieties, both parts cooperate to drive the intermolecular aggregation. This simple but pivotal peculiarity makes amphiphilic molecules soluble in both polar and apolar solvents and able to realize, in suitable conditions, an impressive variety of molecular aggregates characterized by spatially separated apolar and polar domains, local order at short times and fluidity at long times, and differences in size, shape (linear or branched chains, cyclic or globular aggregates, extended fractal-like molecular networks), and lifetime. 

In sodium bis(2-ethylhexyl) phosphate microemulsions, which are composed of cylindrical micelles in the dilute region, it has been observed that the formation of micellar clusters is characterized by a branched structure as the volume fraction (<1>) of the aggregates increases. At d> > 0.2, these clusters mutually overlap, forming a network expanded overall [283]. 

Amyloid Any of a group of chemically diverse proteins that are composed of linear non-branching aggregated fibrils. 

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