Alkyl polyvinylpyridines

Exhaustive studies on well-defined systems are rather scarce (4) nevertheless 3 systems thoroughly analyzed by independant research groups are of outstanding interest a) the quaternization of polyvinylpyridines by alkyl halogenides (20-25) b) the chlorination of polyethylene (13,26-28) c) the basic or acid hydrolysis of PMMA (29-31). On the other hand, neighbouring groups effects have been quantitatively taken into account for the kinetic analysis of periodate oxidation of amylose (32,33). 

Furthermore, 41 % hydrogen fluoride/ polyvinylpyridine combined with jV-bromosuccinimide as coreagent has been used in the preparation of alkyl fluorides from alcohols (Table 18) in good yields. 

Polysoaps belong to a class of compounds which incorporate both of the features of polyelectrolytes and micelles into a single structure, and forms intramolecular micelles having a structural organization related to micelles formed from simple surfactants. Because of the high charge density at the surface and a compact hydrophobic core, they provide interesting microenvironments. A typical polysoap 22 can be formed throu treatment of polyvinylpyridine with linear alkyl halides (33). 

The alkaline hydrolysis in the pr ence of polymer micelles (polyvinylpyridines quatemized by long alkyl drains) was described in a previous section. It was recently found that tire microenvironment provided by polymer micelles gives rise to a remarkable rate enhancement of some hydroxamate anions. Kunitake, Shiirkai, and Hirotsu quatemized polyvinylpyiidine with lauryl and ethyl groups 18. The N-metiiyl-myristohydroxamate anion (MMHA anion) solubilyzed by the catioiric polymer micelle 18 diowed a remarkable nudeophUicity toward phenyl esters 105). Table... 

Polymers from 16C and 18C, and presumably 17C, may be hydrogenated to form the corresponding poljrvinylpiperidines (6), or oxidized to the corresponding water-soluble N-oxide. The polyvinylpyridines may also be readily derivatized via quaternization with an appropriate alkylating agent, such as methyl iodide. The monomeric quats are readily water-soluble but can be prone to spontaneous polymerization above critical concentrations (216). The nature of the counterion can also affect the propensity of the quaternized monomers to autopolymerize. 

Hydrophobic associations in aqueous solution have been recognized in polymeric systems for some time. Their ability to enhance viscosity has led to research directed toward modifying existing water soluble polymers with alkyl substituents capable of associating in solution. These have included studies by Strauss et al. on polysoaps from polyvinylpyridine [7], Schulz [8] and McCormick... 

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