What is Vulkollan® ?

In what hardness’s can Vulkollan® be produced?
Standard production hardness’s are 90 and 95 Shore A. For special applications production of 80 Shore A is available too. Rubbers: 25-80 Shore A. Plastics: 55-95 Shore D. Vulkollan: 80-90-95 Shore A. The optimum properties of Vulkollan® are reached at a hardness of 90 Shore A. Vulkollan® 95 Shore A has the advantage of a higher load capacity (circa 15% higher than 90 Shore A), while Vulkollan® 80 Shore A can solve grip problems. 

What elongation Vulkollan® has with respect to other polyurethanes?
Vulkollan® has a high prolongation + high elongation + high rigidity. Vulkollan® 90 Shore A can be lengthened up to 7 times its original length. Plastics and metals:  high elongation + high rigidity, but small prolongation and very small elasticity. Rubbers:  high prolongation, but small elongation/rigidity. 

What is the tear-resistance of Vulkollan®?
Vulkollan® has a very high tear-resistance. Moreover the tear propagation resistance is very good either. Though lower than without tear, the tear propagation resistance according Graves is no match for any other un-reinforced elastomer. Vulkollan® is impassive to tear damage and even when the tread is damaged, the material will not tear on and thus will maintain functional. 

At what temperature Vulkollan® can be utilised?
Vulkollan® stays elastic and shock-absorbing up to -40°C. At temperatures up to 125°C, with the exception of the elasticity modulus, a reversible decrease will show to the most of the properties. The tear-resistance and by that the abrasion are strongly reduced at temperatures over 80°C. At temperatures over 125°C a permanent damage will be shown to the chemical structure.

Is Vulkollan® service-life longer than rubber?

Vulkollan® has an extremely high abrasion resistance and has up to 2 times less volume lost by wear than rubber does. The softer Vulkollan® often has minor wear than the harder one, because the Vulkollan® can turn aside. To obtain optimum wear-resistance, the temperature must not turn out too high.

What is the bonding-strength of Vulkollan®?
DM Wheel Systems make use of a special surface-treatment that achieves an optimum chemical bonding to all metal surfaces (cast-iron, steel, aluminium, stainless steel, etc.). At room-temperature and neutral chemical environment we guarantee a bonding of the Vulkollan® on metals which is equal to the elongation at break of the Vulkollan®.

Can cast- and polymerised Vulkollan® still be machined? Vulkollan® can still be machined; however, one has to deal with the elastic characteristics of the material. DM Wheel Systems has experienced technical people who can turn, mill and drill Vulkollan® without any problems.

Will environmental influences affect the quality of Vulkollan®?
The natural colour of Vulkollan® is yellow/brown. With regard to ultra violet light the colour of Vulkollan® will change to dark/black because of the Desmodur 15. Changes of colour, even unequal, will not affect the quality of Vulkollan®. 

What can be done to the hydrolysis problem?
Hydrolysis is the decomposing of polyurethanes by contacting (warm) water. In warm and humid environments the affection of hydrolysis can be delayed by adding Stabaxol to the Vulkollan®.

Is Vulkollan® an isolator or a conductor?
Vulkollan® is an isolator. After extensive research, Vulkoprin realised to develop an electrical conductive Vulkollan®. This Vulkollan® C has quasi equal properties as standard Vulkollan®, however, the electrical leak resistance is considerable lower than 10^4 Ω (norm for electrical conductivity). Vulkollan® C is produced in the colour black (non-marking!), usual in the wheel industry for antistatic (leak resistance between 10^5 and 10^7 Ω) or electrical conductive (leak resistance < 10^4Ω) wheels.