| Budget Amount *help |
¥1,900,000 (Direct Cost: ¥1,900,000)
Fiscal Year 1988: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1987: ¥1,400,000 (Direct Cost: ¥1,400,000)
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| Research Abstract |
In this work, the polymerization of water-soluble polyvinyl monomers including allyl ammonium salts such as diallyl dimethyl ammonium chloride(DADMAC) and tetraallyl ammonium chloride(TAAC) has been explored in detail in terms of cyclopolymerization and gelation.
The DADMAC homopolymerization has demonstrated some characteristic basic features as follows: 1) cyclopolymerizability is quite high, the cyclization constant K_c being more than 600 mol/L, 2) the cyclic structures of poly (DADMAC) consist predominantly of five-membered rings, and 3) the rate and degree of polymerization of poly(DADMAC) are quite high, i.e., the chain transfer constant to monomer is low compared with those of common allyl monomers. Even in the copolymerization with acrylamide (AA) having quite high reactivity, the cyclopolymerizability of DADMAC was not influenced, but gelation occurred only for the DADMAC/AA(20/80) copolymerization system. On the other hand, gelation was quite enhanced and the resulting hydrogels had remarkably high swelling ratios in the copolymerization of diallyl ammonium chloride(DAAC) with AA.
It was found that the polymerizability of tri-or tetraallyl ammonium chloride is quite low compared to DADMAC; the kinetic study revealed the importance of the degradative chain transfer.
TAAC showed the entirely different gelation behavior from water-insoluble polyvinyl monomers; this may be ascribed to the electrostatic repulsion and/or the steric effect on the intermolecular and intramolecular crosslinking reactions between the polycationic growing radical and the polycationic polymer. Both factors have been discussed in terms of the addition effect of NaCl and the copolymerization with DADMAC or DAAC, respectively.
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