3. The insertion of an acidic group gives the rubber
special properties
• Extra crosslinking
• Better tensile properties
• Higher continuous service temperature
• Chemical resistance
XNBR - Uses & Applications
XNBR - Carboxyl Group &
Special Properties
5. XNBR - Uses & Applications
XNBR versus NBR
Property Traditional NBR XNBR
Hardness Shore A 72 80
Tensile strenght (kgf/cm2
) 269 231
Elongation (%) 490 338
Modulus @ 300% (kgf/cm2
) 130 201
Compression set(%)
@ 22h, 100°C
57,6 36,9
• Compound analysis according to ASTM standard
• It is possible to infer that the raw rubber hardness for XNBR is higher than
conventional NBR hardness..
• Same butadiene content - Carboxyl group effect
• Advantage for conventional NBR in physical properties, HOWEVER, the
comparison is not valid due to the difference between the hardnesses of both
compounds.
XNBR = NITRICLEAN 3350X; NBR = N615B
7. XNBR Property Analysis
XNBR - Uses & Applications
• Comparative basis compound analysis
• NBR - Necessary to correct formulation compound to get to the
hardness of the XNBR compound
• Use of fillers (calcium carbonate & silica) -
Property NITRICLEAN 3350X N-615B
Hardness Shore A 67 67
Tensile strength (kgf/cm.cm) 149 103
Modulus @ 300% (kgf/cm.cm) 32 5
Abrasion (loss in mm3
) 33,5 158
Density (g/cm3
) 1,181 1,439
Tear strength (kgf/cm.cm) 29 18
Compression set(%, 22h @ 100°C) 57,2 65,6
8. Important Topics
• Necessity of insertion of fillers - higher density and loss
of properties
• XNBR - outstanding performance.
• Low density + high hardness of raw polymer
• Good abrasion resistance
• Compression set - points to a higher crosslinking ratio
• Good Tear resistance
XNBR Property Analysis
XNBR - Uses & Applications
9. Modification of traditional NBR with the insertion of
acidic groups - good performance of properties plus
distinct advantages:
• Better tensile properties
• Higher continuous service temperature
• Very good hardness/density balance
• Alternative to traditional NBR in harsher application
conditions
• Wide range of application in technical artifacts
XNBR - Summary
XNBR - Uses & Applications