Emulsion polymerisation
A method of inverse emulsion polymerisation using an oil phase comprising a hydrocarbon oil obtainable from a gas to liquids process (a GTL oil) is described, in addition to an emulsion comprising a GTL oil and the use of a reaction product of an alk(en)yl substituted succinic anhydride and an amino alcohol to emulsify the emulsion.
1. A method of making a polymer by inverse emulsion polymerisation which comprises the steps of:
(i) forming an emulsion comprising an aqueous phase of polymerisable monomers dispersed in an oil phase comprising a GTL oil, wherein the GTL oil is a hydrocarbon oil obtained from a gas to liquids (GTL) process, wherein the emulsion also includes a surfactant which is obtained by reacting an alk(en)yl substituted succinic anhydride and an amino alcohol at a molar ratio of 1:at least 1.05, and
(ii) polymerising the polymerisable monomers to form an emulsion of the aqueous phase comprising the resulting polymer, in the oil phase.
2. The method according to claim 1 wherein the GTL oil is obtained from a Fischer-Tropsch process.
3. The method according to claim 1 wherein the oil phase comprises less than 10% mineral oil by weight of the oil phase.
4. The method according to claim 1 wherein the surfactant is part of a surfactant system which further comprises a co-emulsifier.
5. The method according to claim 1 wherein the alk(en)yl substituted succinic anhydride is a polyisobutylene succinic anhydride (PIBSA).
6. The method according to claim 1 wherein the amino alcohol is diethanolamine (DEA).
7. The method according to claim 1 wherein the polymerisable monomers comprise (meth)acrylamide or a derivative thereof.
8. The method according to claim 1 wherein the resulting polymer is a cationic or anionic polymer.
9. An emulsion comprising an aqueous phase and an oil phase, wherein a polymer is included in the aqueous phase, wherein the oil phase comprises a GTL oil and wherein the emulsion further comprises a surfactant which is obtained by reacting an alk(en)yl substituted succinic anhydride and an amino alcohol at a molar ratio of 1:at least 1.05.
10. An emulsion according to claim 9 wherein the alk(en)yl substituted succinic anhydride is a polyisobutylene succinic anhydride (PIBSA).
11. An emulsion according to claim 9 wherein the amino alcohol is diethanolamine (DEA).
12. An emulsion according to claim 9 wherein the polymer comprises (meth)acrylamide monomer.
13. An emulsion according to claim 9 wherein the viscosity of the emulsion is less than 2000 mPa·s at 20° C.
14. An emulsion according to claim 9 wherein the oil phase comprises less than 10% mineral oil by weight of the oil phase.
15. An emulsion according to claim 9 wherein the aqueous phase is dispersed within the oil phase.