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I’ll be the last to say I fully understand the details described in either patent disclosure.
But the ‘English’ portion of the description, especially that relating to prior art, does answer a lot of questions.  Besides, I slept in a Holiday Inn last night and we all know Walter Ray sleeps in his van

Both patents describe the basic ingredients of urethane resins (polyols and isocyanites)
They both acknowledge the principle ingredient which turns regular urethane into what we know as ‘reactive urethane’ is a popular plasticizer, TXIB, manufactured by Eastman Chemical.  Both say the amount of plasticizer used is approximately 50% by weight compared to the baseline urethane components. Yikes!  The BASF patent is more specific about the function of the plasticizer, indicating that it is not intended to be part of the final cured compound. As a ‘non-reactive dilutant’ it is uniformly dispersed throughout the mixture while the urethane cures. The result is an array of porous voids in the urethane matrix.  Since the cure process takes place at elevated temps, once cooled, the plasticizer contracts, leaving additional volume for better oil absorption as a bowling ball.
    The BASF patent indicates that the TXIB, being a plasticizer, does impact the strength of the urethane matrix, causing much of the porous structure to collapse on itself during the cure.  Their intent was to alter the strength of the urethane formulation to create a more durable porous structure within the shell. Mechanical properties and oil absorption rates are measured for the samples produced for the patent application.

The Bayer patent is not as explicit about the function of the TXIB. They attempt to replace the TXIB with their own plasticizer formulation. Similar to BASF, the mechanical properties of suitable formulations are provided. However, no mention of any resulting porous structure or oil absorption rates is made.

FWIW
-bill

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