These are some questions that intitially come to mind.

• How does using other alkaline materials change the effectiveness of the gel or emulsion?
• What about working at a lower pH range? Shelburne Museum conservators have been working at a pH of about 7.5-8 and only briefly tried working with a gel that had a pH of between 6-7, but found that it wasn't effective with the carousel panels.  The Pemulen technical information sheet from Noveon indicates that Pemulen TR2 can emulsify up to 60-80% of oil by weight at a pH range of 4-5. This might prove interesting when using the gel in some circumstances.
• Could there be any benefit to adding in a chelating acid such as citric acid to the gel mixture? We had tried this briefly at Shelburne Museum with the carousel panels project, but found that the resulting emulsion was too difficult to control.
• suggestion from Chris Stavroudis (via telephone to Nancie Ravenel, 4/22/09) - create 2 stock gels at the same pH - 1 made with ammonium hydroxide and 1 made with TEA.  Mix the two gels to adjust the active amount of TEA within the cleaning gel.
• question from Dale Kronkright: I am VERY interested which direction, why and by how much the pH is shifting over time. Can you describe in greater detail?

• Another suggestion from Chris Stavroudis (via telephone 2/12/2010): since TEA acts as an alcohol at a higher pH (around 8.5), could one make a Pemulen gel with something other than TEA as the base, add ethanol to the water, and then have a gel that could remove maintenance linseed oil.