Liquid-liquid phase transition compositions and processes
The present application pertains to liquid-liquid phase transition compositions and processes. In one embodiment a liquid-liquid phase transition process comprises first forming a composition comprising a glycol polymer and water and then phase transitioning the composition at or above the composition's cloud point temperature to form at least two liquid phases. The enthalpy of liquid-liquid phase transition may be greater than 5 kJ per kg as measured by a calorimeter and each liquid phase may have unique and advantageous properties. In another embodiment the application pertains to compositions suitable for liquid-liquid phase transition compositions.
1 . A liquid-liquid phase transition composition comprising:
a solvent;
a glycol polymer; and
a glycol ether selected from an alkylene glycol alkyl ether, a dialkylene glycol alkyl ether, a trialkylene glycol alkyl ether, an alkylene glycol dialkyl ether, or any combination thereof wherein alkyl is a C1-C6 alkyl;
wherein enthalpy of a liquid-liquid phase transition is greater than 5 kJ per kg as measured by a mixing calorimeter;
wherein the glycol polymer is less than about 18% by weight of the composition.
2 . The composition of claim 1 wherein the glycol polymer comprises a polypropylene glycol.
3 . The composition of claim 1 wherein the glycol polymer comprises a polyethylene glycol.
4 . The composition of claim 1 wherein the glycol polymer comprises a block co-polymer.
5 . The composition of claim 4 wherein the block co-polymer is selected from PEG-Ran-PG, or PPG-PEG-PPG, or PEG-PPG-PEG, or any combination thereof.
6 . The composition of claim 1 wherein the glycol polymer has an average molecular number greater than or equal to 1,000 and less than or equal to 3,000.
7 . The composition of claim 1 wherein the solvent comprises water.
8 . The composition of claim 1 wherein the glycol ether comprises diethylene glycol.
9 . The composition of claim 1 wherein the glycol ether is diethylene glycol monohexyl ether.
10 . The composition of claim 1 wherein the composition comprises a cloud point temperature above which a liquid phase comprising glycol polymer forms due to a liquid-liquid phase transition and wherein a density of the formed liquid phase comprising glycol polymer is less than 1 gram per mL when non-contiguously separate and at 10° C. according to ASTM D1122.
11 . A glycol polymer composition comprising:
from about 1 to about 80 percent by weight of total composition of at least one polypropylene glycol having a number average molecular weight greater than or equal to 2,000 and less than or equal to 3,000;
from about 1 to about 99 percent by weight of total composition of water;
wherein
(1) the composition comprises a single liquid phase combined solution at a temperature below 5° C.; and
(2) enthalpy of liquid-liquid phase transition is greater than 5 kJ per kg as measured by a mixing calorimeter;
wherein the composition further comprises from about 0.5 to about 50 percent by weight of a glycol ether selected from an alkylene glycol alkyl ether, a dialkylene glycol alkyl ether, a trialkylene glycol alkyl ether, an alkylene glycol dialkyl ether, or any combination thereof wherein alkyl is a C1-C6 alkyl;
wherein the cloud point temperature of the composition is less than about 18° C.
12 . The composition of claim 11 further comprising a density reducing reagent.
13 . The composition of claim 11 further comprising a density enhancing reagent.
14 . The composition of claim 11 wherein the glycol ether is diethylene glycol monohexyl ether.
15 . The composition of claim 11 wherein the polypropylene glycol comprises a block co-polymer.
16 . The composition of claim 15 wherein the block co-polymer is selected from PEG-Ran-PG, or PPG-PEG-PPG, or PEG-PPG-PEG, or any combination thereof.
17 . A glycol polymer composition comprising:
from about 20 to about 25 percent by weight of total composition of at least one polypropylene glycol; and
water;
wherein the enthalpy of liquid-liquid phase transition is greater than 20 kJ per kg as measured by a mixing calorimeter and wherein the cloud point temperature of the composition is less than about 18° C.;
wherein the composition further comprises greater than 0 up to about 5 percent by weight of a dialkylene glycol alkyl ether wherein alkyl is a C1-C6 alkyl.