Phthalocyanine can generate water-soluble stable complexes with copper, diamond, nickel and other metals. The ketone phthalocyanine produced with copper has a very bright blue color, called phthalocyanine blue. The introduction of 16 chlorine atoms on the four benzene rings of copper phthalocyanine produces a polychloride of copper phthalocyanine, called phthalocyanine green.
Phthalocyanine pigments are polycrystalline compounds, of which α and β types are more common. Their stability is different, beta type is more stable than alpha type. When the crystallization is transformed from α type to β type, the crystalline particles often increase, and the coloring power decreases. As the coloring power is high is often alpha type, so the general commercial pigment is mostly alpha type. For the color light, α type of phthalocyanine blue is red light, and β type is cyan light.
In addition to symmetric diacyl peroxide initiators, there are also asymmetric diacyl peroxide initiators. Asymmetric diacyl peroxide initiators have high activity. For example, acetyl cyclohexanesulfonyl peroxide has a decomposition temperature of only 31°C. The decomposition speed is very fast, and it is easy to oxidized wax recipe cause dead-end polymerization when used alone. Generally, it is used in combination with other initiators.
4. Peroxy esters
Commonly used peroxy ester initiators in industry are listed in Table 4-4. The activity of peroxy ester initiators is mainly determined by the stability of the acyloxy group. The more stable the free radicals generated after decarboxylation of acyloxy radicals, the more active the initiator. Phenyl radicals are the most active, so tert-butyl peroxybenzoate is the most stable, tert-butyl peroxyacetate is less stable, and tert-butyl peroxide is the most active. But their activity is lower than that of the corresponding diacyl peroxides. For example, the decomposition temperature of dibenzoyl peroxide is 73℃, and the decomposition temperature of tert-butyl peroxybenzoate is 105℃, so this type is mostly used for high temperature polymerization. reaction.
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