Mold release
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From: Albrecht via MotorcycleKB.com on 19 Jul 2007 17:54 Rick Cortese wrote: >I can give you a specific products where I was forced/overruled to >switch from compatible plasticizer to use of an additional incompatible >one because it had lower water solubility. The suit/pHd's theory was the >incompatible highly water insoluble plasticizer would stick around >longer then the water insoluble one and give better performance. From >the testing I was able to do the theory was wrong but we got stuck with >the formulation anyway and the polymer would literally sweat plasticizer. Yabbot, plasticizer oils that extend the rubber's dynamic range of elasticity are not the same as green tire outside paint. http://www.rheinchemie.com/rc.nsf/id/ECF3D720A5FF6A33C1256D58004E555E Rhenodiv® aqueous tire paints Rhenodiv® outside tire paints provide excellent air venting between the uncured tire and the metal mold to eliminate blemishes and appearance defects. They allow the rubber components to smoothly flow and knit without interference. This is one of a few mold release agents I found during a google search and other mold releases will show up in the google side panel. -- Message posted via http://www.motorcyclekb.com
From: Albrecht via MotorcycleKB.com on 19 Jul 2007 17:56 Rob Kleinschmidt wrote: >You can assume your new tire may not have 100% >of its normal traction for the first hundred miles, or >assume that it's at 100% as you leave the shop. Race compound tires in particular will not have full traction until heated up on the race track. They are shipped in the partly cured (green) condition, and they cure fully during heat cycling. The rubber becomes harder and stronger but has less traction. -- Message posted via http://www.motorcyclekb.com
From: Rick Cortese on 19 Jul 2007 20:05 Albrecht via MotorcycleKB.com wrote: > Rick Cortese wrote: > > >>I can give you a specific products where I was forced/overruled to >>switch from compatible plasticizer to use of an additional incompatible >>one because it had lower water solubility. The suit/pHd's theory was the >>incompatible highly water insoluble plasticizer would stick around >>longer then the water insoluble one and give better performance. From >>the testing I was able to do the theory was wrong but we got stuck with >>the formulation anyway and the polymer would literally sweat plasticizer. > > > Yabbot, plasticizer oils that extend the rubber's dynamic range of elasticity > are not the same as green tire outside paint. > > http://www.rheinchemie.com/rc.nsf/id/ECF3D720A5FF6A33C1256D58004E555E > > Rhenodiv® aqueous tire paints > > Rhenodiv® outside tire paints provide excellent air venting between the > uncured tire and the metal mold to eliminate blemishes and appearance defects. > They allow the rubber components to smoothly flow and knit without > interference. > > This is one of a few mold release agents I found during a google search and > other mold releases will show up in the google side panel. > I mention it only in that mold release is not the only thing that blooms to the surface/coats/slicks up polymers. They could be telling the truth about mold release and still be compounding tires such that half a dozen other things are producing the same effect. A specific instance could be something like a stearate<soapy or hard water scum Calcium Stearate type thing> added to the rubber compound to reduce heat build up under flex that blooms to the surface during manufacture and reduces or eliminates the amount of release agent you need to use. As a formulator, you do this kind of 'engineering' to increase production rates, eliminate EPA type of hurdles to jump, keep the 'magic' out of the hands of the operators. Rick
From: Rob Kleinschmidt on 19 Jul 2007 20:59 The Older Gentleman wrote: > Rob Kleinschmidt <Rkleinsch1216128(a)aol.com> wrote: > > Last tire I bought, I did an accidental burnout leaving > > the tire place. Apparantly it was more glopped up with > > whatever than most new tires. > I thought everyone knew to scrub in new tyres gently before giving them > full lean, as it were? I thought I was being careful when this happened. Hot day, soft pavement, and as I said, perhaps more glop on the tire than usual. 7-8 paris of tires on the same bike and still a mild surprise.
From: Paul Cassel on 21 Jul 2007 18:42
kml wrote: > Does any one have any empirical evidence for the existence of new tire > "mold release" other than anecdotal folklore? > what do you think keeps tires from sticking to the mold if not mold release? |