Thickeners and Rheology Modifiers
Pages: 32 Published: Jan 2012
THE PERFORMANCE EXPECTATIONS OF COATINGS have grown substantially over the past few decades, and the rheological requirements for storage, handling, application, and post-application flow properties have become more demanding. Thickeners and rheology modifiers (TRMs) play a key role in many coating performance properties, and consequently, they are among the most important components in coatings systems. Although TRMs are used in minor amounts in most formulations and are generally considered additives, aqueous coatings usually contain at least one and sometimes two or more TRMs to obtain the desired balance of performance properties. Due to present-day environmental concerns and the use of TRMs predominantly in aqueous coatings, the focus of this chapter is on water-borne coatings where TRMs are used extensively in architectural, construction, elastomeric, and industrial applications. TRMs also find utility in some solvent-borne coatings—discussed later in this chapter, where they function primarily as flow modifiers and thixotropes. A list of some coating properties controlled or influenced by thickeners are found in Table 1. A recommended overview of coatings rheology and rheological test methods is found in Chapter 36 on “Rheology and Viscometry.”
Paper ID: MNL12213M
ASTM International is a member of CrossRef.