Maybe it's not as crosslinked as you think. (Keeping up with Compounding).

Compounders frequently check cure levels in crosslinked compounds by measuring torque in a curemeter or rheometer. The assumption is that torque is proportional to crosslink density. But a computer simulation model calibrated with real crosslink data shows this method grossly overestimates crosslink density.

Robert Johnston, research associate at DuPont Dow Elastomers LLC in Freeport, Texas, reported his surprising results at the SPE ANTEC meeting in San Francisco in May. Data were obtained with the company's SimPolyMod software. Johnston worked with four grades of DuPont Dow's Engage ethylene-octene polyolefin elastomer. He found that torque tests can't distinguish actual crosslinks from elastically active, trapped entanglements, which also affect properties, and entanglements of dangling chains, which contribute little to material al properties. Tel: [phone], www.dupont-dow.com