CYMEL® 328

BENEFITS of CYMEL® 328

• Fast cure response

• Low formaldehyde release

APPLICATION AREAS of CYMEL® 328

• Can and container coatings

• Waterborne coatings

• Automotive coatings

PHYSICAL PROPERTIES of CYMEL® 328

SOLUBILITY of CYMEL® 328

COMPATIBILITY of CYMEL® 328

BACKBONE POLYMER SELECTION of CYMEL® 328

CYMEL® 328 resin contains a combination of methoxymethyl, methylol and imino functionalities making it a very effective crosslinker for backbone polymer resins containing hydroxyl, amide and carboxyl functional groups, such as alkyd, polyester or acrylic resins. CYMEL® 328 resin is very reactive and has a tendency to self-condense at normal baking temperatures, providing films with very good hardness, flexibility, gloss, chemical resistance and outdoor durability. CYMEL® 328  resin is very good compatible and stable with a wide range of waterborne polymer systems.  Although the optimum level of CYMEL® 328 resin should be determined experimentally, ratios of 25 to 35% based on resin solids are typically most effective.

CATALYSIS of CYMEL® 328

CYMEL® 328 resin may not require the addition of an acid catalyst to the formulation to obtain effective cure. In many instances, the acidity of the backbone polymer   in the formulation is sufficient to catalyze the reaction under normal baking conditions (15 minutes at 120 - 150°C). If catalyst addition is required, then 0.5 -  1.0%  of CYCAT®  296-9  catalyst based on total resin solids is recommended.

FORMULATION STABILITY of CYMEL® 328

It is essential that a tertiary amine,  such as dimethylethanolamine or triethylamine,   be used for neutralization and pH adjustment. For optimum stability, a pH of 7.5 - 8.5 should be maintained.

STORAGE STABILITY of CYMEL® 328

CYMEL® 328 resin has a shelf life of 180 days from the date of manufacture when stored at temperatures between 5°C and 32°C. Although lower temperatures are not   detrimental to stability,  its viscosity will increase, possibly making the resin difficult to pump or pour. The viscosity will reduce again on warming,  but care should be taken to avoid excessive local heat as this can cause an irreversible increase in viscosity. Beware of freezing.