Metal ion inorganic antimicrobial agent is loaded with antimicrobial function of metal ions in a variety of inorganic natural or synthetic mineral carrier, the use of carrier slow release of antimicrobial active ions, so that the product has an antibacterial and bactericidal effect.
One of the best application of metal ions are Ag +, Cu + +, Zn + +, etc.. Oxide type antimicrobial agent is the use of N-type semiconductor materials, such as: TiO2, ZnO, Fe2O3, WO3, CdS, etc. under photocatalysis, the adsorption of OH- and H2O molecules on the surface oxidation into a strong oxidizing ability of OH- radicals, to inhibit and kill microorganisms in the environment. In addition to the above two inorganic antimicrobial agents, there are also peroxides, inorganic acids and bases, and metals that can be ligated with fibers.
The decomposition of organic peroxides is generally a first-order reaction, but certain solvents can increase the decomposition rate of peroxides and make the decomposition deviate from the first-order reaction. The main reason is that the generated free radicals further induce the initiator to decompose.
One free radical induces the decomposition of one initiator molecule, and only one free radical is generated. Although the decomposition rate of the initiator is accelerated, the initiation efficiency is reduced. Table 4-17 lists the decomposition rate of dibenzoyl peroxide in different solvents.
Similarly, the monomer also affects the decomposition rate of the peroxide initiator, mst wax additive and the effect of different monomers on the decomposition rate of dibenzoyl peroxide.
Decomposition half-life of dibenzoyl peroxide in various monomers (80℃)
It can be seen that monomers with high activity, such as methyl methacrylate, styrene, acrylonitrile, etc., can capture free radicals faster, reducing the probability of initiator-induced decomposition and prolonging the half-life. On the other hand, monomers with low activity, such as vinyl acetate, are slow to capture free radicals and are prone to induced decomposition, so the half-life is short and the initiation efficiency is low.
Selection of the amount of initiator In the case where the initiator activity matches well with the polymerization conditions such as polymerization temperature and feeding mode, the amount of initiator can be used to adjust the relative molecular weight of the polymer. The amount of initiator is large, the relative molecular mass of the polymer is small, and the amount of initiator is small, the relative molecular mass of the polymer is large.
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