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Random copolymers main characteristics

The general structure of random copolymers of PO-EO and copolyether triols (PO-EO) is presented in Figure 4.18. The main characteristics of the random copolymers of PO-EO, heteropolyether triols, which are used most, are presented in Table 4.7. [Pg.97]

Table 4.7 The main characteristics of polyether triol random copolymers (PO-EO heteropolyether polyols) ... Table 4.7 The main characteristics of polyether triol random copolymers (PO-EO heteropolyether polyols) ...
The main peculiarities of phase separation of polyampholytes - random copolymers of 2M5VP-AA that are insoluble at the lEP - were considered by authors [63-65] from the colloid chemical point of view. Tables 7 and 8 summarize some physico-chemical characteristics of polyampholytes used. The surface tension O, viscosity [rj] and electro conductivity x of PA-3 solution and dispersion are minimal at the lEP (Fig. 13). In the semilogarithmic coordinates the dependence of surface tension o on IgC has breaking points. They correspond to the critical concentration of polyampholytes that reflects the saturation of the adsorp-... [Pg.147]

The poly(alkylene oxide)s are linear or branched-chain polymers that contain ether linkages in their main polymer chain structure and are derived from monomers that are vicinal cyclic oxides, or epoxides, of aliphatic olefins, principally ethylene and propylene and, to a much lesser extent, butylene. These polyethers are commercially produced over a range of molecular weights from a few hundred to several million for use as functional materials and as intermediates. Lower polymers are liquids, increasing in viscosity with molecular weight. The high polymers can be thermoplastic. Solubilities range from hydrophilic water-soluble polymers that are principally derived from ethylene oxide, to hydrophobic, oil-soluble polymers of propylene oxide and butylene oxide. A wide variety of copolymers is produced, both random copolymers and block copolymers. The latter may be used for their surface-active characteristics. [Pg.1]

The ultimate mechanical properties of HDPE/iPP blends can also be improved by adding a suitable third component, mainly a random ethylene-propylene copolymer (EPM). Such an additive, having intermediate molecular characteristics between the two polymer species, can act as a compatibilizing agent" in their amorphous regions. [Pg.127]

The examination of rj t2 values for hundreds of different comonomers polymerized by different mechanisms (2) reveals that in the overwhelming majority of cases these r, r2 values are close to or less than 1 very few examples of ionic processes were found with rjr2>l (J69). For this reason the appearance of a significant number of cases with rir2>t can be regarded as characteristic of complex catalysis. The mentioned tendency is especially pronounced when the comonomers have alkyl groups of different size (ethylene—4-methylpentene-l, pro-pyIene-butene-1, propylene-styrene, propylene-4-methylpentene-l, pro-pylene-vinylcyclohexane). On the other hand, when the alkyl groups are of similar bulkiness (4-methylpentene-l-vinylcyclohexane, 4-methyl-pentene-l-3-methylbutene-l, vinylcyclohexane-styrene), the copolymers obtained are mainly random or have a tendency to alternation. [Pg.150]


See other pages where Random copolymers main characteristics is mentioned: [Pg.449]    [Pg.462]    [Pg.40]    [Pg.69]    [Pg.71]    [Pg.421]    [Pg.210]    [Pg.17]    [Pg.242]    [Pg.40]    [Pg.3746]    [Pg.302]    [Pg.24]    [Pg.211]    [Pg.116]    [Pg.200]    [Pg.725]    [Pg.249]    [Pg.452]    [Pg.317]    [Pg.105]    [Pg.58]    [Pg.9]   
See also in sourсe #XX -- [ Pg.98 ]




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Copolymers characteristics

Random copolymer

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