Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Mixing of two or more solid polymers; mixing of solid...
Reexamination Certificate
2005-02-22
2009-08-25
Rábago, Roberto (Department: 1796)
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
Mixing of two or more solid polymers; mixing of solid...
C525S329200, C525S329300, C525S338000, C525S340000, C525S370000
Reexamination Certificate
active
07579410
ABSTRACT:
Nitrile rubber polymers, optionally hydrogenated, having lower molecular weight and narrower molecular weight distribution than those known in the art, are prepared by metathesis of nitrile butadiene rubber, optionally followed by hydrogenation. The process comprises the steps of a) reacting a nitrile rubber in the presence of at least one compound which is a ruthenium or osmium based indenylidene complex and optionally b) hydrogenating the resulting lower molecular weight nitrile rubber using standard techniques known in the art. The optionally hydrogenated nitrile rubber, with lower molecular weight and narrower molecular weight distribution has very good heat resistance, excellent ozone and chemical resistance and excellent oil resistance. It is used in automotive, oil, electrical, mechanical engineering and shipbuilding industries.
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Lanxess Inc.
Rábago Roberto
Seng Jennifer R.
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