Cyclopolymerization preparation

A vast range of symmetrical and unsymmetrieal 1,6-diene monomers has now been prepared and polymerized and the generality of the process is well established.98,1 A summary of symmetrical 1,6-dienc structures, known to give cyclopolymerization, is presented in Table 4.4 In many cases, the structure of the repeat units has not been rigorously established. Often the only direct evidence for cyclopolymerization is the solubility of the polymer or the absence of residual unsaturalion. In these cases the proposed repeat unit structures are speculative. 

An alternative method of preparing the saturated cyclic amines via cyclopolymerization of diallylamine or diallylammonium chloride was unsuccessful. Common free radical initiators such as 2,2 -azobisisobutyronitrile, ammonium persulfate, benzoyl peroxide were found to be ineffective. Several procedures reported in the literature were followed, and unfortunately all of them have resulted only a small amount of low molecular weight oligomers. Further research for polymerization conditions and types of initiation is still required. 

The hydrolytic stability of water soluble poly[N-(4-sulfo-phenyDdimethacrylamide] (PSPDM) was studied at 90 C in aqueous solutions at pH 7, pH 1.2 (0.1M HC1), and pH 12.3 (0.1M NaOH). PSPDM, which possesses predominantly 5-mem-bered ring imides, was prepared by the cyclopolymerization and subsequent sulfonation of N-phenyldimethacrylamide. No detectable PSPDM imide hydrolysis occurred after 30 days at pH 7 or pH 1.2. Under basic conditions, however, complete hydrolysis to amic acid occurred after one day. The resulting Nsubstituted amide was extremely stable to further basic hydrolysis. 

Polysaccharide analogue, polyether 15, prepared through anionic cyclopolymerization, was chemically bonded to silica gel.73 The CSP resolved several a-amino acids the chiral recognition abilities of the analogue of 15 have been evaluated.74... 

Crosslinkable reactive mesogens, (VI), were prepared by O Neill et al. (3) for use in electroluminescent devices. Crosslinking occurred by cyclopolymerization as illustrated in Eq. (1). 

Although the polymerization of diene monomers is most familiar for 1,3-dienes, as in the production of rubbers, the polymerization of 1,6-dienes to yield polymers containing six-membered rings ( cyclopolymerization ) has been well established for many years43. Gibson et al.441 have used cyclopolymerization of 1,6-diynes to prepare polymers which are effectively substituted polyacetylenes, the archetype being the polymerization of 1,6-heptadiyne ... 

One of the first methods employed for the preparation of a derivatized polymer having a fully conjugated PA backbone involved the cyclopolymerization of di-yne monomers to yield a chain containing fused rings, as shown in Scheme 10 for the hexadiyne example [29,30]. 

Another pefluoropolymer of this type has been developed by Asahi Glass and is available on the market under the trade name CYTOP . This polymer is prepared by cyclopolymerization of perfluorodiene. Its structure is shown in Figure 8.2.7... 

Milne [5] prepared polypyrrolidine, (Vlll), by the cyclopolymerization of 1,10-(di-MV-diallyl)decane by UV or thermal radiation. 

Fig. 6 Possible ring structures of poly( 1,6-heptadiynes) prepared via cyclopolymerization. Poly(cyclopent-l-enylene-l-vinylene)s (A) poly(cyclohex-l-ene-3-methylidene)s (B) and mixed structures (C)...

An interesting extension of the cyclopolymerization strategy is the polymerization of allyl acrylate quaternary ammonium salts, where the resulting ester precursor of 7 is easily hydrolyzed by trifluoroacetic acid to the polybetaine [23]. Polyampholyte 8 was prepared by copolymerization with a high excess of DADMAC [24]. 

The editors believe that the scientific community will find this book helpful as a source of advances and developments in the area of cyclopolymerization, and the preparation and properties of polymers with chain-ring structures. 

In the cyclopolymerization of methacrylic anhydride(MA) as a typical 1,6-diene, five- and six-membered ring anhydride structures can be formed, respectively corresponding to intramolecular hh and ht addition of uncyclized radical. The IR spectrum of poly-MA has been tentatively compared earlier with that of poly-MA prepared by dehydration of poly(methacrylic acid)(37) no five-membered cyclized anhydrides were detected, any absorption at higher frequency due to the strain of a five-membered ring being absent. 

Although several systems have been evaluated to determine the structure of the ring formed in cyclopolymerization, very little work has been reported on the original cyclopolymer reported by Butler ( 7) that was obtained from N,N-dimethyldiallyl-ammonium bromide or the chloride. Consequently, we undertook a study of a five-membered quaternary ammonium polymer, poly(l,l, 3,4-tetramethyl-3-pyrrolinium bromide) as a model system. N,N-dimethyl-3,4-dimethylenepyrrolidinium bromide (6 ) was prepared by reacting dimethylamine with 2,3-bis(bromomethyl)-l,3-butadiene (5). In addition to the bromide salt (6), the iodide salt was also prepared by reacting 2,3-bis(bromomethyl)-l,3-butadiene... 

The cyclopolymerization of the title compound (St-Cj-St), C3 cyclopolymerization, is reviewed. The polymerization has the similar behavior to the fluorescence emission of 1,3-diphenylpropane and its derivatives (n=3 rule or C3 rule). The monomer and its derivatives were prepared by the convenient method from the corresponding a-phenethylalcohol derivatives, using dimethyl sulfoxide-ZnCl2 CCl3COOH system. St-C3 St gave a cyclopolymer only by cationic initiators, and the presence of cyclized units in the main chain was elucidated by several spectroscopic analyses and also by the isolation of cyclocodimers obtained from the reaction of the monomer with styrene in the presence of the catalytic amount of CF3SO3H. 

Since monomers used for the cyclopolymerization are rather unusual, but are considered to have the usage as crosslinking agents, a brief discussion of their preparation seems to be beneficial. 

Monomers (V, VI) with one and two oxygen atoms in the linkage were prepared and polymerized by BF3OEt2 in CH2CI2 at 0 °C with 0.06 M of initial monomer concentration (33). The polymer yielded was insoluble in ordinal solvents after drying. Although the detailed analytical data of the polymer were not obtained, it is quite likely that the cyclopolymerization occurred hardly in these cases. It is ascribed to little formation of the sandwich type transition state like (III), since the trans conformation of C-0 bond is preferable. 

Some polymers containing macrocycles in the backbone have been prepared by a cyclopolymerization process. This is a new method for preparing polymers with macrocycles containing oxygen and sulfur atoms in the backbone. An open chain a,o>-diene containing the heteroatoms in the chain was polymerized as shown below (Yokota, 1989). This process has not been used... 

While ring-opening polymerization of camphorsultam was attempted futilely to prepare a new polymer containing a bicyclic structure and a new acidic sulfonamide group in the backbone [115b], radical cyclopolymerization was exploited in the synthesis of 193 nm alicyclic polymers (Fig. 79). Transannular polymerization to form polynortricyclene bearing tert-butyl ester was utilized in radical copolymerization with MA (Fig. 79) [275]. Radical cyclopolymer-... 

Chromatographic separation of the products of reaction of mixtures of two dichlorophosphines with either sodium-naphthalene or magnesium has led to the isolation of (153) and (154). The reaction of a primary phosphine and a dichlorophosphine in the presence of a base has also been used to prepare compounds of these types, - The less sterically crowded (and therefore less stable) diphosphenes (155) have been prepared by the reactions of dichlorophosphines with bis(trimethylsilyl)phosphines and trapped as cycloadducts with dimethylbutadiene. In the absence of a trapping agent, these systems rapidly undergo cyclopolymerization. ... 

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