What rheological additives would you recommend for alkyd cellulose nitrate systems ?
Various kinds of plasticisers can be used for alkyd-cellulose nitrate blends, the most important being phthalates like dibutyl, benzyl butyl, dioctylphthalate and others. These are general purpose plasticisers. The incorporation of non-solvating plasticisers such as castor oil or butyl stearate in addition to the above mentioned solvating plasticisers is advantageous if a high degree of flexibility is required.
In primers and knifing fillers however, non-solvating plasticisers should not be used since they interfere with adhesion.
Plasticiser, alkyd resin and nitrocellulose
should be selected to achieve the desired compatyibility, flexybility and adhesion. The composition of the binder combination can be varied within wide limits. Assessments of many different formulations have shown that the compotion can vary as followa : 1 part nitrocellulose, 0,5 - 4 parts alkyd resin, 0 - 3,5 parts plasticiser.The type and amount of each component will depend on the application. The solvents used must keep the binder and plasticiser in solution in the actual paint and also whilst the paint film is drying. Thinners for nitrocellulose blends not only act as extenders but have the important function of controlling the drying process and flow of the wet film, as well as regulating the
