Patent GB-812390-A (GB)
Title: Polymeric phosphate esters and their production
IPC: C07F9/09
Filed: 1956-06-05
Abstract: Polyphosphate esters useful as lubricant additives are obtainable by a process which comprises heating at a temperature within the range from 90 DEG  to 250 DEG  C. an hydroxyl-containing phosphate ester having the structure: (RO) (R1O)P(O)(OC2H3R11)xOH, wherein R an R1 respectively are alkyl, haloalkyl, aralkyl, aryl, haloaryl, or alkaryl radicals, R11 is an hydrogen atom or a methyl, ethyl or halomethyl radical, and X is a numerical value from 1 to 10, and removing an alcohol or phenol as it is formed in the heating (see Group IV (b)), the resulting polyphosphate esters having the probable structure <FORM:0812390/III/1> or <FORM:0812390/III/2> wherein R, R1, R11 and x are as defined above and y is a number from 2 to 10.  The acylated derivatives of the polyphosphate esters are also stated to be useful as lubricant additives.  The polyphosphate esters may be used as additives for synthetic lubricants and the acylated derivatives are soluble in mineral oils.ALSO:Polyphosphate esters suitable as plasticizers for polyvinyl acetate, and vinyl chloride-vinyl acetate copolymers are obtainable by a process which comprises heating at a temperature within the range from 90 DEG  to 250 DEG  C. an hydroxylcontaining phosphate ester having the structure (RO)(R1O)P(O)(OC2H3R11)xOH wherein R and R1 respectively are alkyl, haloalkyl, aralkyl, aryl, haloaryl, or alkaryl radicals, R11 is a hydrogen atom or a methyl, ethyl or halomethyl radical, and x is a numerical value from 1 to 10, and removing an alcohol or phenol as it is formed in the heating, the resulting polyphosphate esters having the probable structure <FORM:0812390/IV (a)/1> wherein R, R1, R11 and x are as defined above and y is a number from 2 to 10. The hydroxyl-containing phosphate ester used as starting material may be obtained by reacting an oxirane compound of the structure <FORM:0812390/IV (a)/2> with an ester of the formula <FORM:0812390/IV (a)/3> wherein R, R1 and R11 are as defined above.  The reaction is effected by adding the oxirane compound slowly to the phosphate diester maintained at from - 20 DEG  C. to about 80 DEG  C., if desired in the presence of an acidic catalyst, e.g. boron trifluoride or its ethyl ether complex, and of an inert organic solvent free from hydroxyl groups, e.g. an alkyl ether such as ethyl ether, a paraffin or aromatic hydrocarbon such as heptane or benzene or a halohydrocarbon, e.g. ethylene dichloride or chlorobenzene. Specified phosphate diesters are the dimethyl, -ethyl, -butyl, -hexyl, -2-ethylhexyl-octyl, -octadecyl, -2-chloro-ethyl, -2-chloropropyl, -2,3-dichloropropyl, -2-bromoethyl, 2-fluoroethyl, -phenyl, -p-chlorophenyl, 2,4-dichlorophenyl, di-cresyl, and dibenzyl phosphate diesters and specified oxirane compounds are ethylene oxide, propylene oxide, 1,2-epoxybutane, epichlorhydrin and epibromhydrin.  The heating of the hydroxyl-containing phosphate ester to form the polyphosphate product is usually conducted under reduced pressure, e.g. 0.5 to 1 mm. of mercury and an acidic catalyst, e.g. boron trifluoride, stannic chloride or other Friedel-Crafts type catalyst may be present.  The hydroxyl-containing polyphosphate ester product may be reacted, usually at about 100 DEG to 125 DEG  C. with an aliphatic, cycloaliphatic, or aromatic mono- or polycarboxylic acid or acid anhydride.  Specified acids are acetic, caproic, capric, stearic, succinic, methylsuccinic, benzoic, toluic, phthalic, cyclobutane carboxylic, 1,2 - cyclobutanedicarboxylic, monochloracetic, 2-bromobutanoic, chlorosuccinic, p-chlorobenzoic, 3 - chlorocyclopentamecarboxylic, tetrachlorophthalic, phenyl acetic, p-phenyl benzoic, methoxyacetic, o-ethoxy benzoic, and 2,4-dichlorophenoxy acetic acids.  This further reaction is preferably carried out using the acid anhydride in a proportion of 2 mols. per mol. of hydroxyl present in the polyphosphate and an acid esterification catalyst, e.g. sulphuric, hydrochloric or arylsulphonic acid or boron trifluoride may be present.  In examples: (1) the diester ( (C4H9O)2P(O)(OCH2CH2)1.38OH (obtained from ethylene oxide and dibutyl phosphoric acid) is heated at 90 DEG  to 130 DEG  C. for 13 hours under a pressure of 2 mm. mercury to form a hydroxyl-containing polymeric phosphate ester which is then heated with acetic anhydride to block the terminal hydroxyl group; (2) di-(2-ethylhexyl) 2-hydroxyethyl phosphate is heated at 140-152 DEG  C. at 0.5 mm. pressure for 28 hours to form a polymeric phosphate ester, the hydroxyethyl phosphate starting material being obtained by reacting ethylene oxide with di-(2-ethylhexyl) phosphoric acid and having the formula (C8H17O)(OCH2 CH2)1.16OH; (3) an ethylene oxide adduct of diphenyl phosphoric acid of the formula (C6H5O)2O(O)(OCH2CH2)1.75OH is heated at 90-150 DEG  C. for 10 hours at 2 mm. pressure to form a polymeric phosphate of molecular weight 2164; (4) an epichlorhydrin adduct of di-(2-ethylhexyl) phosphoric acid having the formula (C8H17O)2P(O)(OC3H5Cl)1.027OH is heated for 24 hours at 150 DEG  C. and 0.5 mm. pressure to form a polymeric ester of molecular weight 727; (5) the ethylene oxide adduct of dibutyl phosphoric acid having the formula (C4H9O)2P(O)(OCH2CH2)1.224OH i heated for 24 hours at 150 DEG  C. and 1.5 mm. pressure to form a polymeric phosphate product of molecular weight 1198; (6) an ethylene oxide adduct of di-(2-ethylhexyl) phosphoric acid having the formula (C8H17O)2P(O)(OCH2CH2)2.11OH i heated for 16 hours at 150-156 DEG  C. at 1 mm. pressure to form a polymeric phosphate of molecular weight 1482; (7) an ethylene oxide adduct of di-(2-chloroethyl) phosphoric acid having the formula (ClCH2CH2O)2P(O)(OCH2 CH2)1.9 6OH is heated at 150 DEG  C. and 1 mm. pressure with removal of ethylene chlorohydrin to form a light brown rubber-like solid residue; (8) an ethylene oxide adduct of dicresyl phosphoric acid having the formula (CH3C6H4O)2 P(O)(OCH2CH2)2.21OH is heated for 8 hours at 150 DEG  C. and 1 mm. pressure to form a polymeric phosphate ester; (9) an ethylene oxide adduct of di-(2-ethylhexyl) phosphoric acid of the formula (C8H17O)2P(O)(OCH2CH2)4.82OH is heated for 32 hours at 150 DEG  C. and 1 mm. pressure to form a polymeric phosphate ester; (10) an ethylene oxide adduct of dimethyl phosphoric acid of the formula (CH3O)2P(O) (OCH2CH2)1.9 6OH is heated for 6 hours at 150 DEG  C. and 1 mm. pressure to form a polymeric phosphate ester; (11) a propylene oxide adduct of di-(2-ethylhexyl) phosphoric acid of the formula (C8H17O)2P(O)(OC3H6)1.10OH is heated for 36 hours at 150 DEG  C. and 0.5 mm. pressure to force a piymeric phosphate esterol.  The polymeric phosphate ester products are stated to be useful as insecticides, and as flame-proofing agents and the products obtained by acylating the end hydroxyl groups of the polymeric phosphate ester as well as the polymeric phosphate ester products themselves are stated to be useful as lubricant additives (see Group III).ALSO:The invention comprises polyphosphate esters obtainable by a process which comprises heating at a temperature within the range from 90 DEG C. to 250 DEG  C. an hydroxyl-containing phosphate ester having the structure (RO)(R1O)P(O)(OC2H3R11)xOH wherein R and R1 respectively are alkyl, haloalkyl, aralkyl, aryl, haloaryl, or alkaryl radicals, R11 is a hydrogen atom or a methyl, ethyl or halomethyl radical, and x is a numerical value from 1 to 10, and removing an alcohol or phenol as it is formed in the heating, the resulting polyphosphate esters having the probable structure <FORM:0812390/IV (b)/1> or <FORM:0812390/IV (b)/2> wherein R, R1, R11 and x are as defined above and y is a number from 2 to 10.  The hydroxylcontaining phosphate ester used as starting material may be obtained by reacting an oxirane compound of the structure <FORM:0812390/IV (b)/3> with an ester of the formula <FORM:0812390/IV (b)/4> wherein R, R1 and R11 are as defined above.  The reaction is effected by adding the oxirane compound slowly to the phosphate diester maintained at from - 20 DEG C. to about 80 DEG  C., if desired in the presence of an acidic catalyst, e.g. boron trifluoride or its ethyl ether complex, and of an inert organic solvent free from hydroxyl groups, e.g. an alkyl ether such as ethyl ether, a paraffin or aromatic hydrocarbon such as heptane or benzene or a halohydrocarbon, e.g. ethylene dichloride or chlorobenzene.  Specified phosphate diesters are the di-methyl, ethyl, butyl, hexyl, 2-ethylhexyl, octyl, octadecyl, 2-chloro-ethyl, 2-chloropropyl, 2,3-dichloropropyl, 2 - bromoethyl, 2 - fluoroethyl, phenyl, p-chlorophenyl, 2,4 - dichlorophenyl, di - cresyl and dibenzyl phosphate diesters and specified oxirane compounds are ethylene oxide, propylene oxide, 1,2-epoxybutane, epichlorhydrin and epibromhydrin.  The heating of the hydroxyl-containing phosphate ester to form the polyphosphate product is usually conducted under reduced pressure, e.g. 0.5 to 1 mm. of mercury and an acidic catalyst, e.g. boron trifluoride, stannic chloride or other Friedel-Crafts type catalyst may be present.  The hydroxyl-containing polyphosphate ester product may be reacted, usually at about 100 DEG to 125 DEG  C. with an aliphatic, cycloaliphatic, or aromatic mono- or polycarboxylic acid or acid anhydride.  Specified acids are acetic, caproic, capric, stearic, succinic, methylsuccinic, benzoic, toluic, phthalic, cyclobutane carboxylic, 1,2 - cyclobutanedicarboxylic, monochloracetic, 2 - bromobutanoic, chlorosuccinic, p - chlorobenzoic, 3 - chlorocyclopentanecarboxylic, tetrachlorophthalic, phenyl acetic, p-phenyl benzoic, methoxyacetic, o-ethoxy benzoic, and 2,4-dichlorophenoxy acetic acids.  This further reaction is preferably carried out using the acid anhydride in a proportion of 2 mols. per mol. of hydroxyl present in polyphosphate and an acid esterification catalyst, e.g. sulphuric, hydrochloric or arylsulphonic acid or boron trifluoride may be present.  In