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Entangled Sticky Chains

This difference presumably exists because, for multistickcr chains, the dissociation of [Pg.256]

Leibler et al. (1991) have developed a model for this process, which they call sticky reptation. For long chains with many stickers, the self-diffusion coefficient of a sticky reptating chain turns out to be [Pg.256]

For a chain moving by reptation or by sticky reptation, one expects the reptation time, which scales roughly as the 3.5 power of A, to be related to the diffusion coefficient (which scales as N ), by [Pg.256]

The predictions of Eq. (5-10) are in good agreement with measured z values for urazole-modified polybutadienes (Leibler et al. 1991). [Pg.256]

The plateau modulus is given by the usual formula for entangled polymers, Gq vksT, where v is the number of entanglement strands per unit volume of melt that is, [Pg.256]


For example, poly(vinyl alcohol) (PVOH) finds application as an effective adhesive for paper products such as the old-fashioned postage stamps or envelopes. Licking the stamp or envelope flap causes the adhesive to become sticky because water plasticizes the PVOH and lowers the Tg below room temperature. On pressing the stamp to a piece of paper, the polymer chains can entangle and hydrogen bond with the cellulose in the paper. As the water... [Pg.174]

It is the long chains, which may also be condensed together to form branched chains, which, by becoming entangled, make the acid viscous and sticky. [Pg.452]

Water-borne polymers are widely used in personal care products and cosmetics as viscosity thickeners. A viscosity thickener is an extremely important raw material for the cosmetic industry because it brings about texture change. An issue inherent in the use of common linear polymers as thickeners is that they create a sticky feeMng. This feature is most likely to be related to the spiimability of the polymer solution. One of the most suitable alternative candidates for cosmetic thickeners is microgels. Spinnability is probably related to the entanglement of polymer chains and therefore, because of their cross-linked structure, microgels are... [Pg.293]


See other pages where Entangled Sticky Chains is mentioned: [Pg.254]    [Pg.254]    [Pg.215]    [Pg.90]    [Pg.82]    [Pg.290]    [Pg.255]    [Pg.300]    [Pg.272]    [Pg.273]   


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Chain entangling

Entangled chains

Entanglements

Stickiness

Sticky

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