Ring functional monomers

Attempts to elucidate the polymerization or copolymerization kinetics of ethynyl and maleimide-functionalized monomers have been undertaken via vibrational spectroscopy (137). The thermal polymerization of A-(3-ethynyl-phenyl) maleimide (the structure is given in Fig. 48) was studied via IR and Raman spectroscopy. This model compound is interesting because it carries maleimide and ethynyl groups attached to the same aromatic ring. Kinetic studies indicate that both the acetylene and maleimide group react at the same rate, which strongly suggests the formation of a copolymer rather than a mixture of homopolymers. 

Relatively few simple pyrimidine monomers have been incorporated into heterocyclic polymers (70MI11100). By far the greatest efforts with this ring system have involved polymerizable derivatives of nucleic acid bases and related compounds (81MH1102). The majority of this work has involved the synthesis and free radical polymerization of suitable vinyl- and acrylic-functional monomers, e.g. (134)-(136), although epoxy and other derivatives have also been studied. A number of the polymers exhibit base-paired complex formation with natural nucleic acid polymers or synthetic analogues, have found use in... 

Other successful imprintings in pure methanol or methanol-water mixtures were observed with piperazine-based fluoroquinolones like, for instance, ciprofloxacin [79] and ofloxacin [80], respectively. In both cases, the functional monomer is MAA and the interaction is pH-dependent and due to strong ion pairs formed between the piperazine ring of the quinolones and the carboxylate group of MAA. 

While the incorporation of these solublizing groups at the 3-position has yielded PTs that have surmounted the intractability issue and also contain fewer (3-defects, such substitution of the thiophene core necessarily results in the loss of ring symmetry. With these functionalized monomers, two different types of a-linkages now exist since the 2- and 5-positions are no longer equivalent [231, 232]. 

The reactions of vinylcyclosiloxanes and vinylcyclosilazanes with styrene in the presence of RuHCl(CO)(PCy3)2 opened a new route to functionalized monomers for the ring-opening polymerization of cyclosiloxanes and cyclo-silazanes (Eq. 29) [56]. 

Monomer is attacked by some ionic or coordination species (designated X ) at the functional group (designated G) that causes ring opening. This is followed by the attack of the ring-opened monomer on another cyclic unit, and so on ... 

Ring-opening metathesis polymerization was also used recently for the preparation of amphiphilic star-block copolymers [25]. Mo (CH-f-Bu) (NAr) (0-f-Bu)2 was used as the initiator for sequential polymerization of norbornene-type, unfunctionalized and functionalized, monomers. The living diblocks were reacted with endo-ris-endo-hexacyclo- [ 10.2.1.1.3/115>8.02>l 1. O 1-9] heptadeca-6,13-diene, a difunctional monomer in a scheme analogous to the use of DVB in anionic polymerization, to form the central core of the star (Scheme 10). 

Atrazine (the template) has a triazine ring and two amino groups, all of which form hydrogen bonds with appropriate residues in aprotic solvents (Fig. 6.2). Accordingly, methacrylic acid, having a carboxylic acid (hydrogen-bonding site), is chosen as the functional monomer. Acrylic acid is also useful. The two types of interactions at the two amino... 

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