| abstract |
A MINERAL OIL COMPOSITION COMPRISING A NEUTRAL, NONVOLATILE, MINERAL OIL BASE AND, AS A VISCOSITY INDEX IMPROVER, AN EFFECTIVE AMOUNT, FOR EXAMPLE, 0.5-3 WEIGHT PERCENT, OF AN ESSENTIALLY AMORPHOUS, OIL SOLUBLE COPOLYMER HAVING RANDOM REPEAT UNITS DERIVED, ON A WEIGHT BASIS WITH THE COMBINED WEIGHTS TOTALLING 100%, (A) 25-55% FROM ETHYLENE, (B) 37-75% FROM A TERMINALLY UNSATURATED STRAIGHT CHAIN MONOOLEFIN HAVING 3-12 CARBON ATOMS, (C) 0.1-10% FROM A NON-CONJUGATED DIOLEFIN HAVING 518 CARBON ATOMS AND ONLY ONE POLYMERIZABLE DOUBLE BOND, AND (D) 0.1-2% FROM A NON-CONJUGATED DIOLEFIN HAVING 518 CARBON ATOMS AND TWO POLYMERIZABLE DOUBLE BONDS, SAID COPOLYMER HAVING AN INHERENT VISCOSITY OF 0.7-1.8 AS MEASURED ON A 0.1 WEIGHT PERCENT SOLUTION IN TETRACHLOROETHYLENE AT 30*C. AND A WALLACE PLASTICITY OF AT LEAST 16, SAID COPOLYMER FURTHER CHARACTERIZED AS EXHIBITING SUPERIOR PROCESSABILITY AND ISOLABILITY AND GOOD SHEAR STABILITY. |