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Bowling ball chemistry, according to bill.
The following is my interpretation of the offerings cited in this thread.

Bowling ball covers are principally urethane compounds and by themselves have the hardness and coefficient of friction to function as a bowling ball. Did you know there is a regulation for bowling ball hardness (75 ShoreD)?

In the presence of oil, urethanes and everything else have reduced friction or traction on the lanes.

So the bowling gods invented “reactive resin”
The truth is (according to bill with a few references cited above) there is little difference between the actual resins used in either product. However the reactive coverstocks are made porous to  allow for the absorption of lane oil.

The blowing agents used to create porosity are well known plasticizers normally used in the formulation of plastics like PVC to make them softer or more flexible.

However when combined with the ingredients for urethane these plasticizers are intended to only dilute the mixture and not react (form a chemical interaction) with the urethane.
However one of the references did indicated that there is some softening of the urethane by the plasticizers (which forced the resin 'designer' to make harder urethanes)

Prior to the cure phase the plasticizer is uniformly dispersed throughout the mixture of urethane resins and catalyst. Upon heating to approx (140-160F) the urethane becomes a solid while the liquid dispersion of plasticizer expands within. After cooling, the plasticizer contracts leaving a porous matrix within the coverstock material.

TXIB (a clear oily liquid) is one plasticizer mentioned. It has a low vapor pressure and high boiling point (540F). The result is that it is not very volatile and not likely to become a gas during normal cure temperatures or evaporate out of the shell during normal use.

So in all likelihood the majority of the plasticizer dispersed throughout the coverstock during the cure phase of the ball is still there when your ball is delivered, NIB
(Examples in the Bayer patents put the amount of plasticizer at 42%, by weight, of the cover ingredients. YIKES!)

So if you put your NIB ball in the oven and heat it up to 140-150 that would expand the plasticizer close to where it was when the ball was curing, and virtually fill all the voids.

If any the plasticizer has migrated towards the outer portions of the shell, the voids behind the liquid would easily expand upon heating and drive the liquid out.

Additionally lane oil/conditioner which is mostly mineral oil also has a low vapor pressure and relatively high boiling point (500F). Again, it not volatile at room temps and not likely to evaporate out on it own.  

If heated, any oil absorbed by the cover would be the first element to be driven out of the matrix as both the oil and gaseous voids expand. Theoretically it makes sense that you need more heat to remove plasticizers, because they originate deeper in the shell.
But if the ‘HOOK AGAIN’ folks are correct in suggesting that the plasticizer migrates to the shell exterior, any expanding gas in the underlying porosity should  easily drive the liquid out when heated. As stated the HOOH AGAIN folks do not condone the use of heat. My only concern with the HOOK AGAIN approach to removing the liquids with some form of absorbent is the efficiency of their suggested process. But to their credit their story is the one most consistent with the details uncovered to date. So I’d let folks decide for themselves

Well that’s my story and I’m stickin to it.

-bill


Edited on 4/9/2008 5:11 PM

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