Thames-Rawlins Research Group
Coatings Research and Development Activities


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Coatings Research and Development Activities

SoyAA-1 emulsions are typically formulated by replacing butyl acrylate in conventional emulsion formulations with SoyAA-1 (along with appropriate modifications in monomer composition to adjust the latex Tg), and no changes in processing conditions are necessary unlike other flexibilizing monomers such as ethylene that require pressurized reactors.  SoyAA-1 is copolymerizable with a variety of common monomers employed in emulsion polymerization such as butyl acrylate, methyl methacrylate, styrene, and vinyl ester of versatic acid (VeoVa) as well as specialty monomers such as tridecafluorooctyl acrylate, vinyltriethoxysilane, adhesion promoting monomers, and diacetone acrylamide/adipic dihydrazide.  The latexes are amenable for synthesis at 50-52% solids and display particle sizes in the range of 120-140 nm.  Both the monomer and emulsions derived therefrom have been validated to be stable for over a year at ambient conditions and over six weeks at 50 °C.

SoyAA-1:MMA latexes have been successfully formulated at varying proportions of the two comonomers.  The latexes exhibit successively lower Tg and minimum filming temperature (MFT) values with increasing SoyAA-1 levels.  Quantitative replacement of butyl acrylate with SoyAA-1 yields latexes with lower initial Tg values that increase progressively with time via auto-oxidative drying.  For instance, a latex formulated with SoyAA-1:MMA :: 46.4:53.6 (by weight) with cobalt drier (1% Co metal on latex solids) displayed a Tg increase of ~ 13 °C upon drying for eight weeks at ambient conditions.

Emulsions synthesized with SoyAA-1 have been successfully formulated into zero VOC, waterborne architectural coatings that have been validated to perform competitively against commercial latexes formulated into coatings as well as commercial waterborne architectural coatings.  In another application, SoyAA-1 emulsions were formulated into low VOC, waterborne Navy Haze Gray (NHG) coatings as a potential replacement for current NHG coatings that are formulated from solvent-based silicone-modified alkyds that contain high amounts of VOCs (336 g/L).  The SoyAA-1 based NHG coatings are characterized by very low VOC content (< 15 g/L), fast drying rates, and meet military specifications MIL-PRF-24635C and MIL-PRF-24596A.  Additionally, the waterborne coatings intrinsically offer the advantages of ease of clean-up, reduced fire hazards, and low toxicity to Navy personnel.  The coatings have passed initial trials at the Naval Research Laboratory, Washington DC, and are undergoing evaluation onboard the USS Ponce to simulate and characterize the coatings in actual use conditions.


The TRRG has supported industry for more than 40 years through research and development,
testing and evaluation, formulation, and coatings science educational offerings.

 

 
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