Carbonyl groups poly

Comparison of Table 5.4 and 5.7 allows the prediction that aromatic oils will be plasticisers for natural rubber, that dibutyl phthalate will plasticise poly(methyl methacrylate), that tritolyl phosphate will plasticise nitrile rubbers, that dibenzyl ether will plasticise poly(vinylidene chloride) and that dimethyl phthalate will plasticise cellulose diacetate. These predictions are found to be correct. What is not predictable is that camphor should be an effective plasticiser for cellulose nitrate. It would seem that this crystalline material, which has to be dispersed into the polymer with the aid of liquids such as ethyl alcohol, is only compatible with the polymer because of some specific interaction between the carbonyl group present in the camphor with some group in the cellulose nitrate. 

Very few graft copolymers based on poly(arylene ether)s have been synthesized, probably because of their chemical inertness. Klapper et al. reported grafting the polystyrene or polyisoprene onto the poly(ether ether ketone ketone) (PEEKK) by anionic deactivation.229 The carbonyl groups on tire backbone can be attacked by the polystyrene monoanion or polyisoprene anion (Mn about 3000). Due to the steric hindrance only about 30% of tire carbonyl groups can be reacted. 

White or colored gels are obtained with poly (vinyl alcohol) 26), by using the water-soluble salt of an aromatic amide where the hydroxy and carbonyl groups of the amide are attached to the same benzenoid ring. Several such compounds are illustrated in Figure 3. 

A layer of poly (vinyl alcohol) forms a gel when treated with aqueous alkaline solutions of acylacetamides of aromatic amines which have an unsubstituted methylene group between the two carbonyl groups 29). Several examples are illustrated in Figure 5. 

An illustrative example is the work of Clark et al, on the conformation of poly(vinyl pyrrolidone) (PVP) adsorbed on silica 0). These authors determined bound fractions from magnetic resonance experiments. In one instance they added acetone to an aqueous solution of PVP in order to achieve theta conditions for this polymer. They expected to observe an increase in the bound fraction on the basis of solvency effects as predicted by all modern polymer adsorption theory (2-6), but found exactly the opposite effect. Their explanation was plausible, namely that acetone, with ability to adsorb strongly on silica due to its carbonyl group, would be able to partially displace the polymer by competing for the available surface sites. 

M. Pomerantz, H. Yang, and Y. Cheng, Poly(alkyl thiophene-3-carboxylates). Synthesis and characterization of polythiophenes with a carbonyl group directly attached to the ring, Macromolecules, 28 5706-5708, 1995. 

M. Pomerantz, Y. Cheng, R.K Kasim, and R.L. Elsenbaumer, Poly(alkylthiophene-3-carboxyl-ates). Synthesis, properties and electroluminescence studies of polythiophenes containing carbonyl group directly attached to the ring, J. Mater. Chem., 9 2155-2163, 1999. 

The H- and C-NMR spectroscopic data support the proposed primary structure of poly(Lys-25). The amide carbonyl resonances are particularly informative as these signals are well resolved in the C-NMR spectrum of poly(Lys-25) (Figure 4). An amide carbonyl resonance is observed at 174.9 ppm for poly(Lys-25) that does not appear in the spectrum of poly(Val-Pro-Gly-Val-Gly) [13]. The position and relative intensity of this resonance are consistent with a lysine amide carbonyl group within a peptide bond [14]. Moreover, the resonances of the amide carbonyl groups for other residues in the pentapeptide repeat are split due to the substitution of a lysine residue at position 4 in every fifth pentapeptide in Lys-25. In addition, the absence of splitting in amide carbonyl group of valine in position 4 (174.5 ppm) supports this assignment, as this residue is replaced by lysine in the fifth pentapeptide of the Lys-25 repeat. The presence of other resonances attributable to the lysine residue can be detected in the H- and C-NMR spectra of the Lys-25 polymer at levels commensurate with its... 

Biodegradation of Polyvinyl-Type Poly(sodium carboxylate). PVA is the only substance which is known to be biodegradable in the class of polyvinyl-type synthetic polymer. It may be biodegraded by oxidizing hydroxyl group of PVA to the corresponding carbonyl group and subsequent hydrolysis as shown below (17, 18). 

As a design to develop a polyvinyl-type poly(sodium carboxylate), acrylate copolymers containing hydroxyl or carbonyl groups which are susceptible to the enzymatic reaction, were prepared. It is presumed that the copolymer is first cleaved at a hydroxyl or carbonyl group as in the case of PVA, then the resultant acrylate oligomer is further assimilated by the microbes. The biodegradation of oligomeric acrylic acid (11), in fact, occurs as shown in Table I. 

A variation of GTP, referred to as aldol GTP, involves polymerization of a silyl vinyl ether initiated by an aldehyde [Sogah and Webster, 1986 Webster, 1987]. Both initiation and propagation involve nucleophilic addition of the vinyl ether to the aldehyde carbonyl group with transfer of the trialkyl silyl group from vinyl ether to the carbonyl oxygen (Eq. 5-82). The reaction has similar characteristics as GTP. The product is a silated poly(vinyl alcohol) (PVA), which can be hydrolyzed by acid to PVA (Eq. 5-83). 

The polymerization of the carbonyl group in aldehydes yields polymers, referred to as poly-acetals, since they contain the acetal repeating structure... 

Other polymers undergo cyclization, but there are no commercial applications. Poly (methacrylic acid) cyclizes by anhydride formation and poly(methyl vinyl ketone) by condensation (with dehydration) between methyl and carbonyl groups. 

PolyCmethacrylic acid) was used as template for polymerization of N-vinylpyrrolidone. Interaction between poly(methacrylic acid) and N-vinylpyrrolidone is based on the hydrogen bonding between COOH groups and carbonyl groups in the monomer ... 

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