Organic antimicrobial finishes can be divided into two categories, namely, soluble and non-soluble. Dissolving type antimicrobial finishing agents are not chemically combined with the fabric, so they can be carried away by contact with water, and these types of antimicrobial finishing agents are mainly used on disposable textiles (disposable textiles).
The common soluble antimicrobial agents are: aldehydes, phenols, alcohols, certain surfactants (such as quaternary ammonium salts), organic heterocyclic compounds (such as pyrazoles, pyrimidines, pyrroles), organic metal compounds (such as organic mercury compounds, organic copper compounds, organic zinc compounds, organic lead compounds, organic tin compounds and some other organic metal compounds), etc.
Unsaturated polyester coatings, most of which are cured at room temperature to form a film, can only use a redox initiation system. The peroxide and reducing agent must be soluble in unsaturated polyester, otherwise it will affect the gloss and transparency of the coating. At the same time, attention should polymer wax additive be paid to the matching of peroxide and reducing agent. As mentioned earlier, hydrogen peroxide should use cobalt naphthenate as a reducing agent. For example, cyclohexanone peroxide or methyl ethyl ketone peroxide is combined with cobalt naphthenate.
The peroxide reacts violently with the reducing agent, and there is a danger of explosion when mixed directly. It must be packaged separately to avoid contact, and the paint can be adjusted after both are diluted before use.
The amount of initiator has a great influence on the curing speed. The dosage is large, the coating life is short, the curing speed is fast, the polymer and the molecular weight are small or the crosslinking density is low. The amount of initiator is small, the curing speed is slow, and the history of oxygen inhibition is serious. Generally, the amount of initiator is about 1% of the amount of resin. When using a redox initiation system, the amount of peroxide is doubled. The amount of reducing agent is between 0.12% and 0.5% of the resin.
Selection and use of initiators in emulsion polymerization
Emulsion polymerization is the polymerization reaction of monomers in micelles formed under the action of emulsifiers and mechanical stirring to form polymer emulsions.
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