Many thinks can occur on tackiness, temperature, time for the tackifier to bloom, dilicone influence. My recommendation is to activate the surface of the rubber compound with UV to surpass this problem
USE a blend of ENR nad EPDM and you will shr the benefits of both rubbers. IS a difficult composition to achieve those properties but is a good solution - No more than 30 phr of EPDM can be used
compounds used for molding can be used on injection molding with minor adjustement.< But normally problems on injection molding appear on mold design and compound flux. It is necessary a study on gates and runner of your mold
scarring can be caused by air retention or low NBR compound or high viscosith raw material.
If air is trapped, increase the viscosity of the NBR (47-52 Mooney 100C recommended), if there is a lack of pepetization on high viscosity rubber , add 4 phr of zinc stearate when processing the rubber.
Due to elastomer characteristic, you will never have the same sizes for an elastomer, only a range for it. This change depends on production process, filler mixing, temperature of curing and curing process. My sggestion is that you produce your aluminum backshell with the silicone inside, to...
Sorry rubber is a viscoelastic material, and I think that you will not replicate it on Abacus. This is is due the their nature that can be defined as a behaviour of a spring and an absorber on the same time.
Please see details on the Maurice Morton book "Rubber Technology", about this phenomenum.