Spontaneous polymerization of amphiphilic vinyl monomers, 3. Further studies on spontaneous polymerization of sodium alkyl 2‐hydroxy‐3‐methacryloyloxypropyl phosphates in micellar and reverse micellar systems

Abstract

Addition of sodium chloride and some surface active agents to the micellar or reverse-micellar solution of sodium alkyl 2-hydroxy-3-methacryloyloxypropyl phosphates (C,-AHMP) surprisingly changed the ability of spontaneous polymerization. Low-reactive C,-AHMP in water became spontaneously polymerizable upon addition of NaCl to achieve a conversion of ca. 100%, and the non-reactive C,,-AHMP turned out to be highly reactive upon addition of an equimolar amount of sodium dodecyl glyceryl phosphate in water and in benzene. On the other hand, the high reactivity of C ,,-AHMP decreased upon addition of the surfactants. These results indicate that the additives modify the monomer aggregation state, and that there is a state of aggregation that is most suitable to generate the initiating radical species. The NMR measurement of the proton spin relaxation time gave important information on the aggregation state. In the spontaneous copolymerization of CI2-and C,,AHMP in water, the total conversion decreased with increasing feed content of the C,, monomer, but the residual monomer ratios were equal to the initial ones. ESR spectra were detected directly in the spontaneous polymerization system of C,,-AHMP in both water and benzene. The polymerization of C,,AHMP initiated with a prepolymerized solution of C,,-AHMP showed that some portion of the polymer radicals remained active for 2-3 h at room temperature, after the first-stage polymerization of C,,-AHMP was complete. a) Parts 1 and 2 cf. ref. b,

Spontaneous Polymerization of Amphiphilic Vinyl Monomers V. Effect of Sodium Chloride on Spontaneous Polymerization of Sodium Dodecyl 2-Hydroxy-3-methacryloyloxypropyl Phosphate

“…These results suggested that the presence of NaCl modified the monomer aggregation state to check the generation of initiating radical species, contrary to the case of C 8 -AHMP. 3 As shown in Table II, the increase of NaCl added decreased the T 1 values, especially those of terminal methyl protons in long chain alkyl. Table III shows the comparison of the T 1 values of Cn-AHMP, having different alkyl chain, with the spontaneous polymerizabilities in the absence and presence of NaCl.…”

“…II, 1993 converted it to be high reactive. 3 The discussion described above is summarized in Figure 1, as conceptual illustration.…”

“…2 • 3 Addition of an inorganic electrolyte, sodium chloride, to the micellar solution of lowreactive C 8 -AHMP increased the spontaneous polymerizability to produce the polymer quantitatively at 35°C, and this behavior was related to the decrease of T 1 values with increasing amount of NaCl added. 3 In connection with elucidation of the relation between monomer aggregation state and …”

“…2 • 3 Addition of an inorganic electrolyte, sodium chloride, to the micellar solution of lowreactive C 8 -AHMP increased the spontaneous polymerizability to produce the polymer quantitatively at 35°C, and this behavior was related to the decrease of T 1 values with increasing amount of NaCl added. 3 In connection with elucidation of the relation between monomer aggregation state and * To whom correspondence should be addressed. spontaneous polymerizability, the present report deals with the modification of micellar state of sodium dodecyl 2-hydroxy-3-methacryloyloxypropyl phosphate (C 12 -AHMP), having the highest spontaneous polymerizability among Cn-AHMP, 2 by adding NaCl.…”