The main mechanism of action of KP-M20 is that in the process of cell division of pathogenic microorganisms, it can combine with microtubule proteins of spindle filaments, and then dry mitosis, thus effectively inhibiting the reproduction and growth of pathogenic bacteria and interfering with the synthesis of deoxyribonucleic acid.
As an inhibitor of DNA/RNA synthesis, the auxiliary component has excellent antibacterial effect on many kinds of bacteria, molds, yeasts and algae, and especially has strong ability to kill molds. The anti-mold performance is comparable to that of organic mercury and organic tin.
The macromolecularization of photoinitiators is mainly to solve the compatibility problems, migration problems and odor problems that may exist in small molecular photoinitiators. The molecular weight of macromolecular photoinitiators is often not high, and they are mostly viscous liquid, and have good miscibility with the resin system. Secondly, the molecular chain generally contains multiple initiator units, which can be formed on one macromolecule at the same time when light is irradiated. A free radical, the local free radical concentration can be very high. The local high concentration effect can effectively deal with oxygen inhibition and accelerate the photopolymerization, but the probability of the coupling termination of the active hdpe wax suppliers free radicals in the macromolecule will also increase. By designing the molecular structure, the intramolecular free radical coupling can be reduced. The photochemical behavior and mechanism of macro-molecular photoinitiators are not essentially different from those of small-molecule precursors, and may differ in quantity.
According to the position of the photoactive group, the macromolecular photoinitiator can be divided into side chain type and main chain type. The photoactive group is divided into two types: cleavage type and oxygen abstraction type according to the mechanism of action. . Therefore, macromolecular photoinitiators can be divided into four categories: side chain cleavage type, main chain cleavage type, side chain hydrogen abstraction type and main chain oxygen abstraction type. The side chain cleavage type macroinitiator has the function of multifunctional photosensitive crosslinking agent, and it is also a more successful type at present. The side chain cleavage type macromolecular photoinitiator can generate macromolecular side chain free radicals during photolysis, so when initiating the polymerization of monofunctional monomers, most of them can produce a considerable proportion of grafted polymers.
HCP K-1 and HCP K-2 [formula (7-13)] can be obtained by macromolecularization of the classic photoinitiator HCP K, in which HCP K-1 is esterified because the hydroxyl group [ao, aC is connected to an electron withdrawing group Compared with HCP K before modification, the photoinitiation activity can be reduced by an order of magnitude. The effect of HCP K with chloromethylated polystyrene, although the grafting efficiency is not high, generally only about 10%, but it is sufficient as a macromolecular photoinitiator, and there is no electron withdrawing group on aC, photoinitiated The activity is much higher than HCP K-1.
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