Continuous process for preparing nanodispersions using an ultrasonic flow-through heat exchanger

1. A continuous process for preparing nanodispersions comprising:

providing a composition including a liquid and a solute;

heating the composition to dissolution of the solute to form a solution including the solute dissolved in the liquid;

directing the heated solution through a continuous tube, the continuous tube having a first end for receiving the solution, a continuous flow-through passageway disposed in an ultrasonic heat exchanger, and a second end for discharging a product stream; and

treating with ultrasonication the heated solution as the solution passes through the continuous flow-through passageway disposed in the ultrasonic heat exchanger to form the product stream including nanometer size particles in the liquid.

2. The continuous process of claim 1 , wherein the solute includes a conjugated polymer.

3. The continuous process of claim 1 , wherein the solute comprises:

a semiconducting material including a compound of the formula

wherein A is a divalent linkage;

R 1 and R 2 are each independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, alkoxy, substituted alkoxy, a suitable hetero-containing group, a halogen, perhaloalkyl, alkoxyalkyl, siloxyl-substituted alkyl, and polyether;

n is an integer from about 2 to about 5,000;

the divalent linkage A is selected from the group consisting of

or a combination thereof; and

each R′ and R″ is independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, halogen, —CN, and —NO 2 .

4. The continuous process of claim 1 , wherein the heating the composition heats the composition to a temperature from about 50° C. to about 110° C.

5. The continuous process of claim 1 , wherein the directing the heated solution directs the heated solution through the continuous tube at a controlled rate.

6. The continuous process of claim 1 , wherein the continuous tube has a selected geometric configuration, diameter, length, or combination thereof, selected in order to achieve a desired volume, residence time, and feed rate of the heated solution.

7. The continuous process of claim 1 , wherein the treating the heated solution comprises:

treating with ultrasonication at a frequency from about 20 kHz to about 10 Mhz; and

cooling the heated solution in the ultrasonic heat exchanger to a temperature from about −30° C. to about 45° C.

8. The continuous process of claim 1 , further comprising:

collecting the product stream in a product receiving vessel; and

filtering the product stream.

9. The continuous process of claim 8 , wherein the product stream comprises the nanometer size particles in a dispersion having a Z-average particle size from about 1 to about 1,000 nanometers and a monomodal particle size distribution.

10. The continuous process of claim 1 , wherein the process is isolated from ambient oxygen so that a device prepared with the product stream has a higher mobility, a higher current on/off ratio, and a lower off current.

11. The continuous process of claim 8 , wherein the filtering the product stream comprises in-line filtration of the product stream directly from the ultrasonic heat exchanger discharge end.