Stabilizer oligomer

Second, what type of residues are best at the a and d sites This is also a difficult question to answer direcdy because, as will be addressed in more detail over the next few sections, the nature of residues at these sites influences coiled-coil stability, oligomer state, partner selection, and helix-helix orientation (Table I). However, in general terms, natural coiled-coil sequences tend to use the aliphatic hydrophobic residues (Ala, lie, Leu, Met, and Val) at these positions, rather than the aromatic hydrophobic side chains (Phe, Trp and Tyr) (Parry, 1982 Woolfson and Alber, 1995). The reason for this is probably a combination of bulk and steric constraints presented by the aromatic residues. However, a thorough understanding of the possible exclusion of aromatic side chains from coiled-coil... 

Timasheff s preferential interaction mechanism also explains the influence of solutes on the degree of assembly of multimeric proteins. Preferentially excluded solutes tend to induce polymerization and stabilize oligomers since the formation of contact sites between constituent monomers serves to reduce the surface area of the protein exposed to the solvent. Polymerization reduces the thermodynamically unfavorable effect of preferential solute exclusion. Conversely, preferential binding of solute induces depolymerization because there is greater solute binding to monomers than to polymers. 

Figure C2.3.11 Key surfactant stmctures (not to scale) in emulsion polymerization micelles containing monomer and oligomer, growing polymer particle stabilized by surfactant and an emulsion droplet of monomer (reservoir) also coated with surfactant. Adapted from figure 4-1 in [67],...

Cyanoacrylate adhesives cure by anionic polymerization. This reaction is catalyzed by weak bases (such as water), so the adhesives are generally stabilized by the inclusion of a weak acid in the formulation. While adhesion of cyanoacrylates to bare metals and many polymers is excellent, bonding to polyolefins requires a surface modifying primer. Solutions of chlorinated polyolefin oligomers, fran-sition metal complexes, and organic bases such as tertiary amines can greatly enhance cyanoacrylate adhesion to these surfaces [72]. The solvent is a critical component of these primers, as solvent swelling of the surface facilitates inter-... 

Monomer-soluble initiators are used in this polymerization technique. The monomer phase containing an initiator is dissolved in an inert solvent or solvent mixture including a steric stabilizer. The polymers or oligomer... 

Pospisil, J. Functionalized Oligomers and Polymers as Stabilizers for Conventional Polymers. Vol. 101, pp. 65-168. 

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