Component composition: 5-chloro-2-methyl-4-isothiazolin-3-one 2-methyl-4-isothiazolin-3-one
Appearance: light yellow transparent liquid
Active ingredient: >=1.5%
pH value: 2-5
Chlorine ratio: 1:2.5-3.5
296nm and 366nm absorption peak 335nm maximum absorption peak
The kind of anion has no effect on the light absorption of iodide salt, but has a strong influence on the polymerization activity. The anion is SbF. SbF has the highest initiation activity, SbF has the weakest nucleophilicity, and has the least inhibitory effect on the growth chain carbocation center. When the counter anion is BFT, the iodine transfer salt initiation activity is the lowest, and BFT is easier to release the stronger nucleophilic F-, which causes the carbocation active center to bind with F- and terminate micronized ptfe wax the polymerization.
The photolysis of diaryliodonium salt can cause homo-cracking and hetero-cracking at the same time, producing super acid and active free radicals. Therefore, iodide salt can not only initiate cationic photopolymerization but also free radical polymerization at the same time. This is the common feature of iodide salt and sulfur U salt photoinitiators. Of course, these two polymerization processes are different in rate. Generally, free radical polymerization is faster, and the polymerization is completed in tens of seconds, while cationic polymerization is slightly slower, and it takes several minutes or longer to complete the polymerization, which is not true synchronous photopolymerization. . Diaryliodonium salt has a high quantum efficiency of super acid production, generally up to 0.65~0.7L38]. The result of the photolysis reaction.
Among them, the latter three are more useful intermediates or products. Carbocations deprive a nucleophilic group from environmental molecules (such as alcohols) to release super-strong protic acids. Strong Lewis acids such as S bFs, PFs, As Fs, BF, etc. produced by anions can interact with alcohols to release super-strong protic acids.
Leave a message
We’ll get back to you soon