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Polymers structural formulae

Some polymers are listed below by either lUPACt (I) names or acceptable trivial (T) names. Draw structural formulas for the repeat units in these polymers and propose an alternative name in the system other than the one given. [Pg.68]

Haward et al.t have reported some research in which a copolymer of styrene and hydroxyethylmethacrylate was cross-linked by hexamethylene diisocyanate. Draw the structural formula for a portion of this cross-linked polymer and indicate what part of the molecule is the result of a condensation reaction and what part results from addition polymerization. These authors indicate that the crosslinking reaction is carried out in sufficiently dilute solutions of copolymer that the crosslinking is primarily intramolecular rather than intermolecular. Explain the distinction between these two terms and why concentration affects the relative amounts of each. [Pg.339]

Therapeutic Function Estrogen Chemical Name Estradiol phosphate polymer Common Name Polymeric ester of phosphoric acid and estradiol Structural Formula r... [Pg.1266]

Write the structural formulas of the monomers of each of the following polymers, for which one repeating unit is shown (a) polyvinylchloride (PVC), —(CHC1CH,),— (b) Kel-F, —(CFC1CF,),—. [Pg.898]

Write the structural formula of two units of the polymer formed from (a) the reaction of oxalic acid (ethanedioic acid), HOOCCOOH, with 1,4-diaminobutane, H2NCH2CH2CH2CH2NFI2 (b) the polymerization of the amino acid alanine (2-aminopropanoic acid). [Pg.898]

The monomer of the conducting polymer polyaniline is the compound aniline (aminobenzene). (a) Draw the structural formula of the aniline monomer. What is the hybridization of the N atom in (b) aniline (c) polyaniline (d) Indicate the locations of lone pairs, if any, in polyaniline, (e) Do the N atoms help to carry the current Explain your reasoning. See Box 19.1. [Pg.901]

Substituted ethylenes in which substituents occur on both carbon atoms (with the exception of the fluoroethylenes) usually are not prone to polymerize, although some of them, such as the maleates and fumar-ates, copolymerize readily with other monomers. The further fact that, with rare exceptions, the monomers unite through the addition of the substituted carbon atom of one unit to the unsubstituted carbon atom of the next permits representation of nearly all vinyl addition polymers by the general structural formula... [Pg.55]

Draw the structural formula for the polymer that you will prepare from phthalic anhydride and ethylene glycol. [Pg.182]

The structural formulae for the monomer and polymer are represented as follows. [Pg.103]

Poly (acetylenes) [16], There are several catalysts available for polymerization of substituted acetylenes. Whereas Ziegler-Natta catalysts are quite effective for polymerization of acetylene itself and simple alkylacetylenes, they are not active towards other substituted acetylenes, e.g. phenylacetylenes. Olefin-metathesis catalysts (Masuda, 1985 Masuda and Higashimura, 1984, 1986) and Rh(i) catalysts (Furlani et al., 1986 Tabata, 1987) are often employed. In our experience, however, many persistent radicals and typical nitrogen-containing functional groups serve as good poisons for these catalysts. Therefore, radical centres have to be introduced after construction of the polymer skeletons. Fortunately, the polymers obtained with these catalysts are often soluble in one or other organic solvent. For example, methyl p-ethynylbenzoate can be polymerized to a brick-coloured amorph- See the Appendix on p. 245 of suffixes to structural formula numbers. [Pg.220]

FIGURE 2.3 Skeletal structural formulas of a linear polymer (a) and a network (cross-linked) polymer with low cross-linking density (b) and high cross-linking density (c). [Pg.24]

It Is easy to see that the observed etch rates tabulated are Influenced significantly by the resist polymer composition. The aromatic polymers at the top of Table I are clearly most resistant to etching. Curiously, the etch resistance trend Is maintained regardless of plasma type or plasma reactive species, and depends more upon the resist polymer composition or structural formula. [Pg.62]

The polymer resist exhibiting the lowest PE rate or highest etch resistance versus PMMA or oxide is poly(styrene) (see Table IV). This system, like the others of Table IV, is representative of a vinyl pol3mier with general structural formula of -(CH2-CXY)-. Poly(chlorostyrene), a chlorinated derivative of the aromatic poly(styrene), exhibits equal resistance towards all three dry etch processes. Here halogenatlon has not enhanced the etch rate or reduced the resistance as seen before for PTECM, PTFEM, and PMCA nonaromatic systems. Therefore, the aromatic side group must... [Pg.67]

Of the polymer resists with structural formula (CH2-CXY)-from Table IV or of the group of positive behaving e-beam vinyl resist polymers, PMCN Is the most resistant (see Table IV and V). This etch resistance Is attributed to the CN side chain group, which Is a strongly bonded group that cannot be readily cleaved from the polymer backbone by radiation. It Is notable that PMCN... [Pg.68]

Table 4.1. Structural formulae of the basic monomer units comprising the polymer chains of food proteins and food polysaccharides. Table 4.1. Structural formulae of the basic monomer units comprising the polymer chains of food proteins and food polysaccharides.
Proteins are polyamids formed from amino acids having the formula H2N —CHR —COOH therefore different R groups occur along the polymer backbone according to the amino acid sequence in the protein. Write structural formulas for the R groups in the following amino acids ... [Pg.403]

Polymers with triple bonds and heteroatoms in the macromolecule chain were among the first photoconducting polymers [8, 93-96]. The structural formulas for some among nearly seventy polymers investigated may be represented by... [Pg.36]

The alternative method is to calculate 8 for the polymer from the structural formula and the density of the polymer by using the molar attraction constants tabulated by Small (28). [Pg.19]

Polyethylene oxide) [25322-68-3] (PEO) is a water-soluble, thermoplastic polymer produced by the heterogeneous polymerization of ethylene oxide. The white, free-flowing resins are characterized by the following structural formula ... [Pg.337]

In the few examples selected in Figure 6.9, the structural formulae of some important polymers and of the constituent monomers illustrate the general... [Pg.195]

Preceding the discussion of orientational effects in LC polymers, it is worth mentioning that for a nematic and a smectic phase A of LC polymers only the S-effect was discovered and investigated. This started with works U9,124, 137 138), that demonstrated the ability of LC polymers to orient in permanent and alternating electric fields. The structural formulas of some of the polymers and copolymers investigated are given below ... [Pg.227]


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Formulas structural formula

Structural formulas

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