Mature polymer particle

The mechanism of composite particles formation can be explained as follows. During the early steps of the polymerization, free molecules of monomer and PEG-MA react to form copolymers. These copolymers will continue to grow until they reach a critical size and become nuclei. Due to the presence of ethylene oxide groups in the structure of the macromonomer, and also because of the presence of the surfactant, these nuclei can become steady and evolve as mature polymer particles. This scenario also holds for the macromonomer adsorbed on the silica surface. In that case, the growing copolymers are expected to strongly attach on silica via the anchored PEG derivative. Free PEG molecules are also initially present in the suspension medium but it can be anticipated that the particles or at least the... 

The basic principle of such polymerization (in which all reactants are for instance water soluble) is to perform the reaction under the precipitation condition of the formed polymer chains. Then, the formed clusters of chains lead to the particle nucleation step. The colloidal stability of the mature particles originated from the nucleation step is ensured by the use of charged initiator or the use of charged comonomers in the polymerization recipe. In order to maintain the microgel structure rather than resolubilized polymer chains, a cross-linker is absolutely needed to favor the cross-linking efficiency of the precipitated polymer chains under microgel state (Figure 9.4). 

Attachment of various layers to metals is an important process which permits protection of the metal from the environment, but also provides particular properties to the surface. Therefore, metal coating with paints, polymers, surfactants and so forth is an industrial process of wide application and there exists a large variety of methods for this purpose [12]. These properties of passivated product is a function of the interaction between particle surface and additives. The formation of weak and strong bonds between the metal particles and the organic layer depends on the mature of both components. For example, alkanesUanes form veiy stable monolayers on aluminum oxides. The headgroup of the molecule, a trichloro- or trialkoxysilane, forms a covalent bond with surface OH [13]. This process has found industrial applications as a possible substitute for chromate treatments [14]. One of the most... 

This is a new and potentially powerful method to simulate hydrodynamic phenomena. It is still a developing field which might have a big impact on polymer solutions simulations. An application to a polymer chain in solution (in two dimensions) is found in Ref. 78. A hybrid scheme between LGCA and MD was developed in Ref. 79. We feel however that the field has to mature further (and the relation of LCGA dynamics to the atomistic particle dynamics has to be further clarified) before they can be used as a standard tool in polymer dynamics. Once the relation between LGCA the local microscopic dynamics is established, one is tempted to expect a next quantum jump for the hydrodynamic simulations of complex fluids, such as polymers. 

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