How long will it take for heat to flow through this sample?

[examorph]

I have a rubber sample here, basically it is a slice with a diameter of 45mm and a depth of 3mm. If this sample was at 25 degrees Celsius and I applied 180 degrees temperature all around it (top, bottom faces and outside diameter) how long would it take for the centre point (last point to get heated) to reach the 180 degrees Celsius temperature?

The materials thermal properties are:

Thermal Conductivity: 0.36 W/m*K
Specific Heat Capacity: 2 kJ/Kg K

I am really stuck with this and would appreciate any guidance at all. Thank you.

 

[examorph]

Thanks for your reply. Could you please explain how I would find the T coef from these graphs ran at different temperatures?