Bifunctional additives for liquid hydrocarbons obtained by grafting starting with copolymers of ethylene and/or propylene and vinyl ester

Abstract

The disclosure relates to the synthesis and the use of copolymers based on ethylene and/or of propylene and of vinyl ester(s) modified by grafting, effective for improving both the resistance to cold and the lubricity of liquid hydrocarbons in particular the middle distillates originating from the distillation of petroleum and crude oils, in particular those with a low sulphur content and relates to a copolymer including: a) units derived from ethylene of formula A —(CH 2 —CH 2 ) n1 — and/or propylene of formula A′ —((CH 3 )CH 2 —CH 2 ) n2 with n1+n2=n ranging from 98 to 643, preferably ranging from 124 to 515; n1 being advantageously equal to n; b) units of formula B: —(CH 2 —CHOOCR 1 ) m-x — in which R 1 represents a C 1 -C 15 linear or branched alkyl group preferably methyl, propyl, and/or a C5 to C15 branched alkyl group, in which the branching is situated at any point of the alkyl radical, preferably in position 2 or 3 of the alkyl chain; preferably chosen from the preferred C5-C15 vinyl comonomers, preferably chosen from the pivalate, isopentanoate, isohexanoate, isononanoate, isodecanoate and/or isotridecanoate, and advantageously 2-ethyl hexanoate, neoalkanoates, in particular neononanoate, neodecanoate and/or neoundecanoate; with m ranging from 2 to 105, preferably ranging from 16 to 71 and x ranging from 0.2 to 105, preferably ranging from 1.6 to 71; c) units of formula C: —(CH 2 —CHOH) x1 — in which x1 ranges from 0 to 0.30x, preferably x1=0; d) units of formula D: —(CH 2 —CHOOCR 2 ) x2 — in which x2 ranges from 0.70x to x, preferably x2=x, and R 2 represents a C 8 -C 24 saturated or unsaturated, linear or branched, alkyl group, preferably C 14 -C 20 or also C 14 to C 18 with x=x 1 +x 2 .

1 . A use as bifunctional lubricity and resistance to cold additive for liquid hydrocarbon compositions of at least one copolymer comprising:
 a) units derived from at least one of: ethylene of formula A —(CH 2 —CH 2 ) n1 — and propylene of formula A′ —((CH 3 )CH 2 —CH 2 ) n2 , with n1+n2=n ranging from 98 to 643, n1 being advantageously equal to n;   b) units of formula B: —(CH 2 —CHOOCR 1 ) m-x — in which R 1  represents a C 1 -C 15  linear or branched alkyl group, in which the branching is situated at any point of the alkyl radical, with m ranging from 2 to 105;   c) units of formula C: —(CH 2 —CHOH) x1 — in which x1 ranges from 0 to 0.30x;   d) units of formula D: —(CH 2 —CHOOCR 2 ) x2 — in which x2 ranges from 0.70x to x, and R 2  represents a C 8 -C 24  saturated or unsaturated, linear or branched, alkyl group,
 with x=x 1 +x 2 . 
   
     
     
         2 . The use according to  claim 1 , in which the percentage in moles of units A and/or A′ in the copolymer ranges from 79 to 99% in moles, the percentage in moles of units B in the polymer ranges from 0 to 19% in moles, the % in moles of units C in the polymer is close to 0 to 6.3% in moles, the percentage in moles of units D in the polymer is from 0.1 to 21% in moles. 
     
     
         3 . The use according to  claim 1 , in which the at least one copolymer is in the form of a concentrated solution in a hydrocarbon distillate. 
     
     
         4 . The use according to  claim 1 , in which the hydrocarbon liquid composition is a hydrocarbon distillate containing from 0 to 5,000 ppm of sulphur, and contains 10 to 5,000 ppm of said at least one copolymer, optionally in a mixture with other additives such as detergents, dispersants, demulsifiers, anti-foam agents, biocides, reodorants, cetane improvers, anti-corrosion agents, friction modifiers, lubricity, combustion, cloud point, pour point improvers, anti-sedimentation agents and conductivity improvers, resistance to cold additives, lubricants. 
     
     
         5 . The use according to  claim 4  in which the distillate comprises at least one hydrocarbon cut originating from the group constituted by the distillates with a boiling point comprised between 150 and 450° C., an initial crystallization temperature ICT greater than or equal to −20° C., comprising distillates from direct distillation, distillates from vacuum distillation, hydrotreated distillates, distillates originating from catalytic cracking and/or hydrocracking of vacuum distillates, distillates resulting from ARDS type conversion and/or visbreaking processes, distillates originating from the upgrading of Fischer Tropsch cuts, distillates resulting from the BTL conversion of vegetable and/or animal biomass, taken alone or in combination, and esters of vegetable and animal oils or their mixtures. 
     
     
         6 . The use according to  claim 5 , in which the distillate comprises a C9 to C40 n-paraffin content comprised between 1 and 40% by mass. 
     
     
         7 . The use according to  claim 1  of the copolymer, as a distillate additive for Diesel fuel comprising from 0 to 500 ppm of sulphur. 
     
     
         8 . The use according to  claim 1  of the copolymer as a distillate additive for heating fuel oil comprising from 0 to 5000 ppm of sulphur. 
     
     
         9 . The use according to  claim 1  of the copolymer as a distillate additive for heavy fuel oil.