Grafted molecules

PS grafted amount (2) area per grafted molecule (3) prepared... 

We note that charge dissociation behavior of surface-grafted molecules can be very different from that of free molecules [Bain CD, Whitesides GM (1989) Langmuir 5 1370 van der Vegte EW, Hadziioannou H (1997) J Phys Chem B 101 9563]. However, the bulk values can stUl be used to obtain a good estimate of behavior in grafted polyelectrolyte systems... 

If suitable substituents as sterically hindered piperidine groups are located on the grafted molecules, the synthesis of new polymeric stabilizers can be achieved. Such stabilizers can be expected to have a good efficiency in the protection of the parent polymer, especially in the case of thermal ageing. 

Inverse gas chromatography (IGC) is used for the determination of the surface energy characteristics of silicas before and after modification by heat treatment or by grafting onto their surface alkyl, polyethylene glycol) and alcohol chains. Because of its high sensitivity, IGC reveals the nature of the grafted molecules, which may then be confirmed by independent methods. 

This study shows that small and well defined molecules behave in a complex manner when chemically linked to the surface of a solid. Their behaviour is strongly dependent on the characteristics of the graft and the surface, and on geometrical factors like the fractality of the surface. Obviously, the grafting ratio, which determines the intensity of interactions that adjacent grafted molecules experience is also important. 

Figure 8 describes the silica surface as planar on the molecular scale, at least on a scale comparable with the dimensions of the grafted molecules. If this is the case, then odd chain diols, when arranged in trans/trans configurations will have the optimal position to interact with both reactive ends of surface silanols i.e., they will be able to form diesters. 

It has been stated numerous times that polymer-bound reactive intermediates are more stable than the corresponding solubilised counterparts. The stabilisation forces exerted by the polymeric matrix are most probably due to hydrophobic clustering. Polymer-bound peracids are believed to be more stable and not explosive. - The hydrophobic nature of polystyrene resins in combination with the high dilution effect has been used successfully several times to accelerate intramolecular cyclisations by grafting molecules onto a solid support as shown in Chapter 7.6.2>>22... 

Casual or statistical model [143] that supposes that the site of grafting each consequent molecule does not depend on the position of earlier grafted molecules... 

The introduction of functional groups into a grafted molecule can affect the structure of the grafted layer... 

The strategy to modify surface states, and thus the Vg and SRV, is based on interaction of chemically grafted molecules with these states. The key is to find molecules that will modify the semiconductor surface chemistry in a way that involves the surface states. In this respect, the origin of the surface states should be considered. Intrinsic surface states originate from the termination of the crystal bulk and the breaking of chemical bonds at the surface, whereas extrinsic surface states originate from crystal imperfections, such as missing surface atoms, line defects, or... 

As usually used, the term graft copolymer refers to the product of a polymerization technique intended to produce a truly grafted molecule. The term does not necessarily imply that grafting did in fact occur to any significant degree. 

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