Polymeric nanoparticles, manufacturing

Since MEs have become commercially valuable for tertiary oil recovery, in the food and pharmaceutical industry, their characterization has become a pertinent feature of many publications dealing with this type of colloidal systems [4,7,38]. Knowing the microstructure of an ME is of great importance as the phase behavior will influence the ability to solubilize compounds and can determine drug release [39] or influence the manufacture of polymeric nanoparticles from these systems [40]. 

The key objective of this chapter is to provide comprehensive information about the nanoprecipitation method to form polymeric nanoparticles. It provides crucial factors, such as the type of components used and processing conditions (e.g., addition rate of various components and mixing time) that are involved in nanoprecipitation. The chapter comprises a brief discussion on the parameters affecting the size of the nanoparticles and the mechanism of nanoparticle formations. Additionally, the different semps used to mix the phases and the recent advancements in the manufacturing techniques are discussed. Finally, the biomedical applications of the nanoprecipitation technique are conversed. 

Compared with emulsion polymerization and suspension polymerization, the manufacturing process of suspension polymerization of inverse emulsion is more complicated. The advantage of using this technology is to make a capsular structure which has a polymer shell and liquid inner phase. The polymer shell can provide protection by preventing the inner phase from leaking out. When nanoparticles are added to the polymer shell, they can inhibit mass transfer and reinforce the polymer matrix to make the nanocomposites stronger or thermally stable. More importantly, the presence of nanoparticles can partially replace or completely eliminate the use of emulsifiers in the nanocomposite bead synthesis process. One application, as mentioned before, is to make PS nanocomposite... 

Nanoparticles of synthetic polymers are usually manufactured by dispersion of preformed polymers. Although many methods can be used, they may be classified as monomer polymerization, nanoprecipitation, emulsion diffusion/solvent evaporation, and salting out. An appropriate method is selected mainly depending on polymer and drug natures. Polymerization of polymer monomers has been developed usually using poly(alkyl cyanoacrylate) [96,97]. Organic solvents are usually used in polymerization. A detailed description of this method is not provided here. 

Table 2 Methods of Manufacturing Polymeric or Protein Nanoparticles Method...

Nanophase materials feature a three-dimensional structure and a domain size of less than 100 nm. They are usually produced by compaction of a nanoscale powder and are characterized by a large number of grain boundary interfaces in which the local atomic arrangements are different from those of the crystal lattice [11.2]. Nanocomposites, in contrast, consist of nanoparticles that are dispersed in a continuous matrix, creating a compositional heterogeneity of the final structure. The matrix is usually either ceramic or polymeric. Only the manufacturing of ceramic nanocomposites applies the principles of agglomeration (Section 6.7). 

Metal-containing polymers may be produced by various methods, such as chemical reactions of precursors— in particular, reactions of metal salts in polymer solutions, the treatment of polymers with metal vapors, or the polymerization of various metal-monomer systems [1-4], Depending on the metal nature and the polymer structure, these processes lead to organometallic units incorporated into polymer chains, metal-polymer complexes, or metal clusters and nanoparticles physically connected with polymer matrix. Of special interest are syntheses with the use of metal vapors. In this case, metal atoms or clusters are not protected by complexones or solvate envelopes and consequently have specific high reactivity. It should be noted that the apparatus and principles of metal vapor synthesis techniques are closely related to many industrial processes with participation of atomic and molecular species [5]—for example, manufacturing devices for microelectronic from different metals and metal containing precursors [6]. Vapor synthesis methods employ varying metals and... 

J. and Bruggen, B.V. 2010. The use of nanoparticles in polymeric and ceramic membrane structures Review of manufacturing procedures and performance improvement for water treatment. Environ. Pollut. 158 2335-2349. 

Styrene-butadiene copolymers are extremely important to the rubber industry. They are particularly important in tire manufacture. Styrene-butadiene polymer is produced by emulsion polymerization and solution polymerization. Most of the volume is by emulsion polymerization. This affords the opportunity to prepare polymer nanocomposites by several avenues. One can blend an aqueous dispersion of the nanoparticles with the styrene-butadiene latex before flocculation to produce the rubber crumb, disperse an organically treated nanoparticle in the styrene-butadiene solution polymer before the solvent is stripped from the polymer, disperse the organically treated nanoparticles into the monomers, or prepare the rubber nanocomposite in the traditional compounding approach. One finds all of these approaches in the literature. One also finds functional modifications of the styrene-butadiene polymer in the literature designed to improve the efficiency of the dispersion and interaction of the nanoparticles with the polymer. 

There are different manufacturing processes for the production of nanostructured polymeric blends. Peponi et al. reviewed [16] bottom-up and top-down processes for nanostructured polymers and advanced polymeric-based nanocomposites. Nanostrac-tured thermoplastics blends are reported under bottom-up matrix nanocomposites whereas nanostructured thermoplastic nanocomposites are introduced under top-down approaches. Polymer nanotechnologies are characterized by top-down processes including ingredients such as polymer and nanoparticles. They are introduced... 

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