Poly ethyl group substitution

Narrower specificities have been obtained with antibodies to some unusual helical structures. Poly(dG)-poly(dC) induces antibodies specific for the immunogen and unreactive with other deoxyribonucleotide polymers, such as poly(dAT) or native DNA. Double-helical polyribonucleotides with modified furanoses, such as poly(A)-poly(2 -0-methylU), induce antibodies that react with a number of polymers bearing 2 -furanose substitutions (such as methyl or ethyl groups on either the purine or pyrimidine-containing strand). Poly(G)-poly(C) induced antibodies of narrow specificity in our studies, but Lacour and co-workers obtained anti-poly(G)-poly(C) that cross-reacted with several forms of viral RNA. ... 

Poly(vinyl alcohol) readily reacts with a wide variety of Isocyanates In DMSO solution (Equation 1) to produce modified polymers that contain 10-100% of the original hydroxyl groups substituted with carbamate groups. The yields of such reactions are essentially quantitative. Similar results have been reported from other research groups (14-16). tinder these conditions, poly(vinyl alcohol) has been reacted with 3- and 4-chlorophenyl-Isocyanate (this study), phenyllsocyanate (12-14), methyl, ethyl. Isopropyl and 1-naphthyl Isocyanates (14) and methoxymethyllso-cyanate (15,16). The reaction of PVAl with phenyl, tolyl and 4-chlorophenyl Isocyanates In dlmethylacetamlde solutions has also been reported (17). 

Cairns and Neustadter (1975) studied the stability of carbon dispersions stabilized by BP 45, a copolymer of methacrylic esters for which R in the ester group -COOR could be the straight chain C4 or Cg-iz alkyl groups, or the amino substituted ethyl group -CH2CH2NH2. They also studied the stabilizer PV30-TEPA, a succinimide terminated poly(isobutylene). Flocculation was induced by the addition of ethanol to the dispersion medium, which was n-heptane. Their results, which compare the CFVs with the 0-compositions determined by the method of Comet and van Ballegooijen (1966), are presented in Table 9.1. 

Through the introduction of ester groups at the 3-position of the thiophene ring, electrochromic polymers were formed that were more hydrophilic than poly(3-alkylthiophene)s due to the polar ester group substitution. Two examples, poly(3-methyl-butyric acid 2-thiophen-3-yl-ethyl ester) (7a) [63]... 

There is a significant potential of microwave-assisted modification of linear polymers via side group substitution, and the details of two examples pertaining to cellulose and polyphosphazene are presented here. The phosphorylation of cellulose at OH groups, as achieved by the microwave irradiation of a mixture of cellulose, urea and phosphorous acid at 105 °C for 2h, is shown in Scheme 1.6 ]18], while Scheme 1.7 indicates how chlorine atoms of poly(dichlorophos-phazene) can be substituted by microwave heating of the polymer in the presence of ethyl-4-hydroxybenzoate, tetrabutyl ammonium bromide (TBAB), tetrahydrofuran (THF), and NaH for 2h at 65 °C [18]. 

The enolate species 2, derived from methacrylates with bulkier ester groups than MMA, are sterically protected against the access of BujAl under the above-mentioned conditions, even when the porphyrin moiety is a non-ortho-substituted tetraphenylporphyrin. An example is shown by the polymerization of ethyl methacrylate (EMA) using 1 (X=Me) as an initiator, where the growing species have an EtO group in the terminal enolate unit 2 (R=Et). After the addition of BujAl to the system, polymerization proceeded to 100% monomer conversion within 10 min. The Mn of the produced polymer was close to the expected value, and the MWD was narrow (Table 5, run 5). A similar result was obtained for the polymerization of isopropyl methacrylate (PMA) with the 1 (X= Mel- soBujAl system, which quantitatively gave a narrow MWD poly(methacr-ylate) with a predicted Mn (Table 5, run 6). 

This article reports on the synthesis of photosensitive polymers with pendant cinnamic ester moieties and suitable photosensitizer groups by cationic copolymerizations of 2-(cinnamoyloxy)ethyl vinyl ether (CEVE) (12) with other vinyl ethers containing photosensitizer groups, and by cationic polymerization of 2-chloroethyl vinyl ether (CVE) followed by substitution reactions of the resulting poly (2-chloroethyl vinyl ether) (PCVE) with salts of photosensitizer compounds and potassium cinnamate using a phase transfer catalyst in an aprotic polar solvent. The photochemical reactivity of the obtained polymers was also investigated. 

For poly silanes made by Wurtz reaction, the presence of functional groups in polysilane polymers is limited by the vigorous conditions of the sodium condensation reaction. Any substituents that react with molten sodium metal must therefore be introduced after the polymer is synthesized. Halogen atoms can be introduced into alkenylpolysilanes by HBr or HC1 addition reactions, as shown for the 3-cyclohexenyl-ethyl polymers in equation (21).37 Chlorine atoms have also been introduced into arylpolysilanes by chloromethylation, in which -CH2C1 groups are substituted onto phenyl rings in the polymer.38... 

Vinyl copolymers substituted with -OH, -0-R, -0C(0)-R, -C(0)-R, or -C5H4N groups have various practical applications, depending on their composition. These applications include uses in glues, lacquers, protective films, flocculent agents, various formulations in cosmetics (e.g. poly(1-vinyl-2-pyrrolidinone-co-ethyl methacrylate-co-methacrylic acid) is used in hair spray formulations, poly(1-ethenyl-2-pyrrolidinone-co-1-eicosene) is used as a pigment dispersant in cosmetics), etc. A number of pyrolysis studies were done on these materials [43], etc. Some thermal properties of a few common vinyl copolymers are summarized in Table 6.5.14. 

---