The rubber material has for various reasons a very long scorch time.
Taking the 150°C semi-isothermal as an example it is evident that the scorch time (which is about 20 min) could, from a reaction-sequence point of view, safely be shortened to 10 min.
If the scorchtime for the rubber is reduced, it is believed that the adhesiverubbe bond will co-cure more efficiently and hence give a stronger interfacial bond. Another way of dealing with the sequential mismatch would be to use a delayedaction adhesive.