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Nucleation promoter

Other less common nucleation promoters/plasticizers for PET include V-ethyl-toluenesulfonamide and trioctyl trimellitate. [Pg.522]

The three following functional mechanisms may be considered for nucleation--promoting substances (nucleating agents). [Pg.330]

Sioussat T, Boekelheide K. 1989. Selection of a nucleation-promoting element following chemical modification of tubulin. Biochemistry 28 4435 43... [Pg.143]

Undoubtedly, many of the above and other examples have been caused by unintentional seeding. Reference has already been made in section 5.1.2 to the role atmospheric dust can play as a nucleating agent, noting that even foreign bodies in the dust can also act as nucleation promoters. Once a certain crystalline form has been prepared in a laboratory or plant, the working atmosphere inevitably becomes contaminated with seeds of the particular material. If later a thermodynamically more stable polymorph or hydrate (pseudopolymorph) appears, then seeds of this too will enter the atmosphere and play a dominant role. However, it is the speed with which another laboratory or plant, often some large distance apart, sometimes even in another country, also become... [Pg.200]

Plastino J, Lelidis I, Prost J, Sykes C (2004) The effect of diffusion, depolymerization and nucleation promoting factors on actin gel growth. Eur Biophys J 33 310-320... [Pg.201]

The rate can be increased by applying other external modifications, solvents, plasticizers, or nucleation promoters. The extension of chain length... [Pg.51]

As outlined previously the main reason for the interest in optimised surfactants for the liquid carbon dioxide processes lies in their role as nucleation promoters. [Pg.99]

Bose and co-authors have shown that CNTs cause a macromolecular mobility and an onset separation phase temperature reduction. This behavior was attributed to free energy changing and probably an earlier second-phase nucleation promoted by CNT. The anthors have also observed that nanotubes migrate to a preferential phase forming a network-like structure, hindering the phase separation. Figure 1.11a and b show a poly(a-methyl styrene)-co-acrylonitrile/poly(methyl methacrylate) blend (with different proportions) reinforced by MWCNT produced by Bose et al. [34], where the MWCNT are dispersed in one polymer phase only. [Pg.11]

Substrate nucleation promoted by (1) reaction with the substrate (2) a nucleation promoting layer on the substrate, (3) naturally favorable nucleation rate on the substrate or unfavorable rate on the mask. [Pg.592]

Finally, a similar result enhancing selectivity without relying on reaction with the bulk substrate is achieved by coating the substrate with a nucleation-promoting layer that is chemically different from the substrate material. The nucleation layer is covered with a mask where deposition is not desired. The desired film forms only where the promoter is exposed and continues to grow there because of the existence of the nucleus. This method relies on the reaction being heavily nucleation limited. If nucleation can occur on the mask then selectivity may be lost. [Pg.593]

The above methods work best if used together. Simultaneous etching and growth can correct for accidental nucleation on the mask that may result even where there is a difference in reactant supersaturation. The use of a nucleation promoter or an interaction with the substrate to promote nucleation can emphasize nucleation on desired locations enough to allow the etch and growth rates to be more different than would be possible without the nucleation promoter, and so on. [Pg.593]

In PET, nucleating agents and nucleating promoters are typically introduced into injection molded PET-glass fiber composites to accelerate their crystallization rate. PLA crystallization in the injection molding process however has not been thoroughly investigated. [Pg.2317]


See other pages where Nucleation promoter is mentioned: [Pg.521]    [Pg.522]    [Pg.61]    [Pg.77]    [Pg.274]    [Pg.561]    [Pg.346]    [Pg.521]    [Pg.522]    [Pg.186]    [Pg.387]    [Pg.61]   
See also in sourсe #XX -- [ Pg.593 ]




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