Patent GB-836323-A (GB)
Title: Improved stabilising additives for distillate fuels
IPC: C10L1/20
Filed: 1958-06-02
Abstract: Petroleum distillate fuels boiling between 300 DEG  and 900 DEG  F. are stabilized by the addition of a copolymer of the reaction product of epichlorhydrin and an unsaturated polymerizable compound containing a carboxyl group with a vinyl or vinylidene monomer or mixture thereof with another comonomer (see Group IV (a)).  The epichlorhydrin reaction product is preferably a mixed ester of a dibasic acid of the formula <FORM:0836323/III/1> where R is a C8-C24 alkyl group, R1 and R11 are hydrogen or methyl and n is 1-3. Suitable comonomers are styrene, isobutylene, butadiene, allyl acetate, vinyl propionate, methyl methacrylate, allyl ethyl ether, divinyl ether, acrylonitrile or vinyl acetonitrile with which may be mixed lauryl maleate or tallow fumarate.  The copolymer preferably has a molecular weight of 3,000-100,000 and is added in amounts of 0.002-2% by weight to heating oils, diesel fuels or jet engine fuels.ALSO:Mixed esters of unsaturated dibasic acids having the formula ROCOCR1=CR11COO(CH2CH(CH2Cl)O)nH where R is preferably a C8-C24 alkyl group, R1 and R11 are hydrogen or methyl, at least one preferably being hydrogen, and n is 1 to 3 are prepared by reacting a long chain alkyl half ester of the acid with epichlorhydrin.  The acid may be maleic, fumaric, citraconic or mesaconic and the long chain alkyl group derived from straight or branched chain alcohols or mixtures thereof such as dodecyl, cetyl, eicosyl, docosyl, 2 - ethylhexanol - 1, C8 oxo - alcohols, capryl alcohol or the product obtained by hydrogenation of coconut oil (sold under the name "Lorol").  The ester: epichlorhydrin mol. ratio may be 1:1 to 1:4 but is preferably 1:1.  They are reacted in the presence of 0.05 to 5% by weight of BF3 or its etherate, AlCl3 or AlBr3 or a basic catalyst such as NaOCH3 or NaOH. The temperature may be 100-180 DEG  C. and the epichlorhydrin is preferably added to the half ester over 1-2 hours and then reacted for 4-24 hours.  A solvent such as benzene, toluene or xylene may be used.  In the examples: (1) equimolar amounts of epichlorhydrin and isooctyl hydrogen fumarate are reacted in the presence of BF3 etherate at 150 DEG  C. for 17 hours; (3) equimolar amounts of epichlorhydrin and tallow hydrogen maleate are reacted; (5) "Lorol" hydrogen maleate is reacted with epichlorhydrin in equimolar quantities in xylene with BF3 etherate at 155 DEG  C. for 17 hours.ALSO:The reaction product of a polymerizable unsaturated compound containing a carboxyl group and epichlorhydrin is copolymerized with a vinyl or vinylidene compound with or without any other copolymerizable monomer.  The acid reacted with epichlorhydrin is preferably a halfester of an unsaturated dicarboxylic acid, the reaction product having the formula ROCOCR1=CR11COO(CH2-CH(CH2Cl)O)nH where R is preferably a C8-C24 alkyl group, R1 and R11 are hydrogen or methyl, at least one being hydrogen, and n is 1-3.  The acid may be maleic, fumaric, citraconic or mesaconic and the group R may be derived from straight or branched chain alcohols or mixtures thereof such as C8-oxo alcohols or a mixture obtained by the hydrogenation of coconut oil containing principally C12 and C14 alcohols sold under the name "Lorol."  Suitable comonomers are styrene, isobutylene, butadiene, allyl acetate, vinyl acetate or propionate, methyl methacrylate, allyl ethyl ether, divinyl ether, acrylonitrile and vinyl acetonitrile with which may be mixed lauryl maleate or tallow fumarate.  The copolymerization may be effected in solution, e.g. in benzene, at 60-250 DEG  F. and promoted by gamma radiation or the use of catalysts such as benzoyl peroxide or a ,a 1-azo-bis-isobutyronitrile.  The mol. ratio of mixed ester to other monomers may be 2:1 to 1:2.0.  Times of 1-36 hours are used.  The products, preferably of molecular weight 3000-100,000 are used for stabilizing liquid fuels.  In the examples the following copolymers are prepared : (1) chloropropyleneoxy iso-octyl maleate (0.125 mol.), vinyl acetate (1 mol.), and tallow fumarate (0.875 mol.), reacted in benzene for 3 hours at 80-90 DEG  C. in the presence of benzoyl peroxide; (3) chloropropyleneoxy tallow maleate (0.125 mol.), vinyl acetate (1 mol.) and tallow fumarate (0.875 mol.); (5) chloropropyleneoxy "Lorol" maleate (1 mol.) and vinyl acetate (1.4 mol.) in benzene with benzoyl peroxide and 6 megaroentgens of gamma radiation at 110 DEG  F.