SILOXANE-POLYOXYALKYLENE BLOCK COPOLYMERS CONTAINING METHOXYSILOXY GROUPS

1290687 Methoxy-containing siloxane-polyoxyalkylene copolymers UNION CARBIDE CORP 18 Sept 1969 [18 Sept 1968] 45950/69 Headings C3R and C3T [Also in Divisions C5 and D1] A polyoxyalkylene-polysiloxane comprises units R a SiO 4-a/2 wherein each R is a monovalent hydrocarbon group, a methoxy group, or a divalent organic group linking a polyoxyalkylene chain to Si by a C-Si bond, and a is 1, 2 or 3, there being at least 0À05 methoxy groups and at most 0À02 Si-H groups per S i atom and at least one methoxy group and at least one polyoxyalkylene group per molecule, and at least 75 mole per cent of the oxyalkylene groups being oxyethylene groups. In Examples a polysiloxane Me 3 SiO(MeHSiO) 40 SiMe 3 is reacted in turn with allyl methyl ethers of polyethylene glycols in the presence of H 2 PtCl 6 , and then with methanol to give polymers containing 8-24 polyoxyethylene blocks, having 7-34 oxyethylene units each, and 16-32 methoxy groups, and 0À1-1 Si-H group per molecule. The products may be used to impart soil-release properties to textiles, optionally in conjunction with crease-proofing agents, e.g. aminoplast or epoxy resins, sulphones or sulphoxides, and curing catalysts, e.g. MgCl 2 , ZnCl 2 or Zn(NO 3 ) 2 ; they are also useful as polyurethane foam stabilizers and as metal lubricants.