Effect of novolac addition on the creep of acrylonitryl- butadiene rubber(NBR)‎

الملخص EN

The aim of this research is to study the behavior of creep in blended polymer composed of Nit rile rubber and novellas through different novellas percents in addition to its effect on the other mechanical properties.

Results show an improvement in the creep in which elongation under constant load decreases from 15.3mm at 0% novellas to 1.8 mm at 50% novellas at 60 minutes from the test time, i.e.

with 78.9% improvement.

Also results show an increasing in the curing time by 143% and 18% respectively, specific gravity increases by 16.6%, tensile strength by 417.2%, hardness by 140 % all increments take place at 50% novellas, while momentum and flow ability slightly altered.

We conclude that novellas has the ability to improve the general properties of rubber specially creep resistance which is one of the important property in the rubber applications as well as improves the rubber heat resistance which gives a resistance for the rubber against early vulcanization curing, this is due to the cross linking between novellas and formaldehyde results from the decomposition of hexamethylenetetramine (HMTA) at the temperature of recipe mixing.