α-スルホ脂肪酸のアリルエステルの重合
無水硫酸による脂肪酸のα-スルホン化に関する研究 (第5報)
1965 年 14 巻 9 号 p. 500-505
詳細
1965 年 14 巻 9 号 p. 500-505
Allyl α-sulfopalmitate can be polymerized in the aqueous medium in the presence of potassium persulfate.
The polymerized allyl ester is polyelectrolyte and the aqueous solution of this substance shows structural viscosity. This can be well shown by a rheometer with two concentric cylinders.
Since this polymerization reaction was sensitive to oxygen, several factors affecting polymerization, i.e., concentration of initiator and monomer, dissolved oxygen, and polymerization temperature, were investigated. A relation between the rate of polymerization and that of decomposition of initiator, dM/dC (M : monomer, C : initiator), was also estimated and compared with those of the other allyl compounds.
The rate of polymerization was measured by sampling the reaction mixture at a definite time interval followed by determination of the iodine number of each sample with modified Wijs method.
The rate of decomposition of initiator was measured by ferrous sulfate-ceric sulfate method.
The conclusions obtained were as follows :
1. Iodine numbers with modified Wijs mothod, which were measured in the aqueous solution, were approxi-mately in accordance with the results obtained by ordinary Wijs method.
2. The polymerization was largely affected by temperature, for instance, at 70°C it reached to about 90%, whereas at 40°C it was no more than 5%.
3. This polymerization reaction was assumed to be of the second order, and the rate constant was proportional to the concentration of the initiator.
4. The apparent rate constant decreased with the increase of the concentration of the monomer, but the initial rate of polymerization was nearly constant independently from the monomer concentration. The activation energy of the reaction was assumed to be about 36kcal/mol.
5. dM/dC was not constant and increased with the increase of the concentration of initiator, being different from the cases of other allyl compounds.
Thus a linear relation between (dM/dC)2C/M2 and dM/dC was no more substantiated, and the former increased rapidly with the increase of the latter.
