TRIPROPYLENEGLYCOL TRICHLOROMETHYL POLY PHOSPHONATE

1398151 Polyalkylene glycol phosphites and phosphonate derivatives thereof STAUFFER CHEMICAL CO 26 July 1972 [26 July 1971] 34896/72 Heading C2P [Also in Division C3] Phosphite esters of the formula wherein R 1 is an alkyl group, R is the residue of a polyalkylene glycol HO-(R11O) m -H where R11 is a C 2 -C 20 alkylene group, m is the number of repeating units, normally 2 to 20, and n is a number from 2 to 50, and which have an OH number below 200 are obtained by transesterifying a tertiary phosphite ester P(OR 1 ) 3 with a polyalkylene glycol HO(R11O) m H as defined above, the phosphite triester being used in an amount of 1À0 to 1À5 moles per mole of the glycol, The transesterification is completed when two moles of the alcohol (R 1 OH) (e.g. methanol) are evolved. The products may be reacted with less than a stoichiometrically equivalent amount of a halohydrocarbon, especially a carbon tetrahalide, e.g. CCl 4 or CBr 4 , to give a phosphitephosphonate derivative of the formula wherein R 1 is alkyl, R is as defined above, R 2 is an alkyl group optionally substituted with (y-1)X atoms where X is a halogen atom and y is 1 to 4, and n1 and n11 are numbers each being greater than 0 and the sum of n1 and n11 being from 2 to 50. Examples are given for the reaction of tripropylene glycol with triethyl phosphite and dipropylene glycol with trimethyl phosphite to give products of type (I) and for the reaction of CCl 4 with a product obtained by transesterifying dipropylene glycol with trimethyl phosphite to give a product of type II. The products I and II are useful as reactants with polyisocyanates (optionally in admixture with other polyols) to form flame-retardant polyurethane foams.