| 摘要 |
PURPOSE:To obtain a thermally reversible hydrophilic and hydrophobic polymer having a transition temperature different from that of a conventional thermally reversible polyacrylamide derivative and useful for a light screen for a greenhouse or a chemical laboratory, a temperature sensor, a display, etc., by radical- polymerizing a specified vinyl compound. CONSTITUTION:A vinyl compound of formula I (wherein R1 is H or methyl and R2 is a lower alkyl) is radical-polymerized to obtain a thermally reversible hydrophilic and hydrophobic polymer of formula II (wherein R1 and R2 are as defined above). This polymer has such a thermal reversibility of high- temperature hydrophobicity type that it can dissolve in water in a low- temperature range and can not dissolve in water in a high-temperature range. Although the transition temperature of the polymer varies with polymerization conditions, for example, that of poly(N-methoxypropylacrylamide) is 44-48 deg.C in a 1wt%-aqueous solution. Said polymerization is carried out preferably by a solution polymerization process. It is preferable that the degree of polymerization is 0.01-6.0 in terms of an intrinsic viscosity [eta] (as measured in a methanol solution at 30 deg.C).
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