• Underseal

Underseal, e.g. for vehicles, has to protect them from mechanical damages like stoning, but also from corrosion. That means that good adhesive properties, working properties, flow properties and elasticity are requested. Therefore polyvinyl chloride is the basis for this kind of protective coatings.

The compositions of such coatings are as numerous as the demands made on them. The most important components are:

• Vinyl chloride polymeride
• Polyvinyl chloride
• Diethylhexyl phthalate
• Diisononyl phthalate
• Calcium carbonate, treated
• Calcium oxide, and others.

1. In classical plants fats are transesterified in a two-stage batch process. This is normally done in two subsequent batch containers.
2. Using a special IKA® inline dispersing machine of type DISPAX-REACTOR® now gives the possibility to carry out the transesterification in a continuous process in one stage. The raw material is continuously fed.
3. The transesterification reaction takes place in the high-energetic shear zone of the dispersing machine. The raw materials are dissolved to finest droplets, by which the specific surface is enormously enlarged and the mass transfer is decisively intensified. This noticeably accelerates the transesterification reaction and maximizes the output. The complete transesterification can be carried out in one stage and fully automatic.
   

Advantages:

• lower running costs
• lower investment expenditure
• clearly reduced space requirement
• more flexible production

1. Underseal dispersions have very different compositions. Nevertheless, the basis for their production are always vinyl compounds, which are rather viscous and have to be mixed first. Depending on the rheology, softeners and maybe even organic solvents are added, before all other components, especially the treated calcium carbonate, and maybe other fillers, pigments and so on are mixed in.
2. Since all solids already have a very small grain size, homogeneous repartition is the main aim. This is reached using a stirrer with toothed disk, e.g. an IKA®-TURBOTRON®, or the IKA®-ULTA-TURRAX® as "batch" or "inline" machine.