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There is a major question among formulators: How to develop a high-solids polyurethane system with low viscosity for easy application, as well as outstanding performance after cure since voc component in paints and coatings became the primary target of regulations. One solution is to employ low molecular weight polyols to develop a lower viscosity formulation that requires less solvent. Unfortunately, these reductions in molecular weight often lead to systems that heal too quickly and don’t perform well in the field. Without reductions in molecular weight, these polyols have the danger of high intrinsic viscosities which makes it pretty much difficult to eradicate solvent from the formulation. Reactive diluents are low viscosity co reactants specifically developed to reduce VOCs through a reaction with the polymer matrix. They are similar to solvents as they reduce polymer viscosity, but they do so without increasing VOCs. Reactive diluents usually take the form of blocked or delayed sources of active hydrogen. Aldimines and ketimines are examples of blocked amino compounds. Oxazolidines are an example of blocked amino alcohols. Reactive diluents lead to higher solids and reduced viscosity. This property often works well for error-free applications of higher-solids coatings. A potential new way for reactive diluents is the use of different functional moieties to effect cure of coatings. Nowadays, high-solids coatings predominantly rely on the chemistry of hydroxyl functional groups. There is a growing need in the coatings industry to develop new technologies to cure thermo set coatings due to VOC reduction requirements described by regulatory agencies. This objective is accomplished by lowering resin molecular weight. It is commonly known that reducing molecular weight helps in achieving the desired goal of high-solids coatings, but it make formulating and curing of these coatings more cumbersome. Latest higher-solids coatings have enhanced functionality to assure cross linking due to low molecular weight, have more sag tendencies and prone to develop coating defects such as craters, pinholes, pigment flooding and floating etc. Incorez is a specialist manufacturer of oxazolidines, waterborne epoxy curing agents, reactive diluents, and waterborne polyurethane dispersions. The other products are moisture scavenger, latest curing agent, and reactive diluent.
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