| 摘要 |
<p>A fuel oil composition comprises a fuel oil in a major amount, which fuel oil has a mass % against n-alkane carbon number distribution curve characterised by: (i) a maximum negative gradient from carbon number 18 to carbon number 26 that is less than -0.30; and (ii) a ratio of the mass of n-alkanes of carbon number greater than 22 to the mass of n-alkanes from carbon number 18 to carbon number 21 that does not exceed 0.25; and
an additive in a minor amount, which additive comprises at least one ethylene polymer which, in addition to units derived from ethylene, comprises units of the formula (I):
and, optionally, units of the formula (II):
wherein
each R 1 group and each R 2 group independently represents hydrogen or methyl;
each R 3 group independently represents an alkyl group having 5 or more carbon atoms; and
each R 4 group independently represents an alkyl group having from 1 to 4 carbon atoms, and wherein the proportion of units of formula (I) in the or each ethylene polymer is greater than 13 and not greater than 20 mole per cent, and the total proportion of units of formula (I) and of formula (II) in the or each ethylene polymer is greater than 13 and not greater than 25 mole per cent.</p> |
