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Vinyl homopolymers

The most commonly used technique for making C-13 NMR spectral assignments for vinyl homopolymers has been through the use of Bemoullian statistics (29) ( ). If one knows the relative concentrations of either m or r, any particular "n-ad" distribution can be calculated because... [Pg.307]

When measuring vinyl polymer tactlclty, one prefers the longest complete n-ad distribution available as well as the translated simplest comonomer distribution, possibly m versus r. An alternative exists to the m versus r distribution In the form of number average or mean sequence lengths. If any vinyl homopolymer Is viewed conceptually as a copolymer of meso and racemic dyads, mean sequence lengths can be determined for continuous runs of both meso and racemic configurations (32), that Is,... [Pg.309]

In addition to viewing a vinyl homopolymer conceptually as a copolymer of meso and racemic dyads, one may also consider the mean sequence length of "like" configurations (M). In this Instance, the polymer chain Is seen as a succession of different lengths of co-orlented configurations from one to "n", the longest sequence of like configurations, that Is,... [Pg.309]

A (simple) asymmetric chains including most vinyl homopolymers maximum 1 relevant torsion angle in side chains... [Pg.8]

Cyclopolymerization of bifunctional monomers is an effective method of chirality induction. Optically active vinyl homopolymers and copolymers have been synthesized by using optically active distyrenic monomers (41) based on a readily removable chiral template moiety. Free-radical copolymerization of 41a with styrene and removal of the chiral template moiety from the obtained copolymer led to polystyrene, which showed optical activity ([Oc]365 -0.5-3.5°) (Scheme 11.6) [84], The optical activity was explained in terms of chiral (S,S)-diad units generated in the polymer chain through cyclopolymerization of 41a [85], Several different bifunctional monomers have been synthesized and used for this type of copolymerization [86-90]. [Pg.767]

Ribbed helices (costal helices) are important in organic chemistry because linear polymers contain side chains as well as backbones. We may, then, discern not only the catenal helix of the backbone, but the intercostal helix formed by all of the ribs and the infracostal helicesof the individual side chains. The intercostal helix may be iterative (as in an isotactic head-to-tail vinyl polymer or homogeneous poly-a-amino acid) or non-iterative (as in a random copolymer, an atactic polymer or typical protein). The intracostal helices can best be analyzed as short-chain crooked lines, as in Section III. Important as costal helicity is, it is secondary to catenal helicity and we therefore limit our attention to the primary helicity, that of long chains. Indeed, we limit our attention to catenal helices having chain motifs of two atoms and two bonds as found in head-to-tail vinyl homopolymers ... [Pg.44]

Figure 13 Photoresponsive chiral vinyl homopolymers and copolymers. Figure 13 Photoresponsive chiral vinyl homopolymers and copolymers.
We have thus chosen to pursue these studies using vinyl homopolymers labelled with PBD and PPO with a view to elucidating both the fundamental photophysical processes involved in sub-nanosecond excimer formation and also the effect of segmental motion, energy migration and the constraints Imposed by the polymer backbone. [Pg.172]

Electronic Energy Relaxation in Aromatic Vinyl Homopolymers... [Pg.220]

The variety of vinyl homopolymers and copolymers, most containing quarternary centers and synthesized for plasma etch rate ratio evaluation, contain the following monomers to varying proportions ... [Pg.92]

Table 2.6 shows T values of some selected acrylic and vinyl homopolymers expressed in °C. Note the effect of type of alcoholic chain as well as parent monomer structure on the T of homopolymers. The... [Pg.84]

Table 2.6 of some selected acrylic and vinyl homopolymers... [Pg.85]

One-part, UV cure One-part, water-based vinyl (homopolymers modified copolymers) ... [Pg.370]

Palatinol TOTM is a primary branched monomeric plasticizer for vinyl homopolymer and copolymer resins. Palatinol TOTM is suggested for use in those end-use areas where extremely low volatility is required. [Pg.137]


See other pages where Vinyl homopolymers is mentioned: [Pg.57]    [Pg.287]    [Pg.170]    [Pg.1256]    [Pg.19]    [Pg.1610]    [Pg.15]    [Pg.98]    [Pg.145]   
See also in sourсe #XX -- [ Pg.172 ]




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Vinyl homopolymers, copolymers

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