Processes and compositions for cleaning mixing devices to improve polymer production

Patent metadata

Field	Value
Publication number	US-2016186104-A1
Application number	US-201615061384-A
Country	US
Kind code	A1
Filing date	Mar 4, 2016
Priority date	Feb 28, 2012
Publication date	Jun 30, 2016
Grant date	—

Abstract

A cleaning mixture comprising polymeric resin pellets having a Rockwell R hardness of 85 to 140, water, and a surfactant salt comprising at least one of sulfonate salts, C 6 to C 36 carboxylic acid salts, or mixtures thereof, is used to purge the mixing device. The cleaning mixture has a pH of 6.0 to 9.0.

First claim

1 . A cleaning mixture, comprising:
water; thermoplastic polymeric resin pellets having a Rockwell R hardness of from 85 to 140 as measured by ASTM D785; and a surfactant salt comprises at least one of the following: sulfonate salts, C 6 to C 36 carboxylic acid salts, and mixtures thereof; wherein the cleaning mixture has a pH from 6.0 to 9.0.

2 . The cleaning mixture of claim 1 , wherein the surfactant salt is 0.1 wt % to 9 wt % of the cleaning mixture.

3 . The cleaning mixture of claim 1 , wherein the thermoplastic polymeric resin pellets are 70 to 99 wt % of the cleaning mixture.

4 . The cleaning mixture of claim 1 , wherein the water is present in an amount of 0.9 to 12.0 wt % of the cleaning mixture.

5 . The cleaning mixture of claim 1 , wherein the surfactant salt and the water form an aqueous solution with a pH of 6.0 to 7.0.

6 . The cleaning mixture of claim 1 , wherein the surfactant salt and the water form an aqueous solution and the aqueous solution has a viscosity of 20 to 1,000 centipoise as measured by ASTM D445 at 23° C.

7 . The cleaning mixture of claim 1 , wherein the thermoplastic polymeric resin pellets comprise cylinders with an average length of 2.0 to 6.0 mm and an average diameter of 0.5 to 4.0 mm.

8 . The cleaning mixture of claim 7 , wherein the thermoplastic polymeric resin pellets comprise pellets having at least one angular face and wherein the surfaces defining the angular face meet at an angle of 60 to 120 degrees.

9 . The cleaning mixture of claim 8 , wherein the thermoplastic polymeric resin pellets have a bulk density of 0.5 to 0.9 g/cc, as measured by ASTM D1895.

10 . The cleaning mixture of claim 1 , wherein the thermoplastic polymeric resin pellets have a bulk density of 0.5 to 0.9 g/cc, as measured by ASTM D1895.

11 . The cleaning mixture of claim 1 , wherein the thermoplastic polymeric resin pellets comprise pellets having at least one angular face and wherein the surfaces defining the angular face meet at an angle of 60 to 120 degrees.

12 . The cleaning mixture of claim 11 , wherein the angle is 80 to 100 degrees.

13 . The cleaning mixture of claim 1 , wherein the surfactant salt comprises at least one of the following: alkyl aryl sulfonate salts and alkyl sulfate salts.

14 . The cleaning mixture of claim 1 , wherein the cleaning mixture consists of:
70 to 99 wt % of the thermoplastic polymeric resin pellets; and 1 to 30 wt % of an aqueous solution that contains 0.2 to 30 wt % of the surfactant.

15 . The cleaning mixture of claim 1 , wherein the surfactant salt and the water form an aqueous solution and wherein the thermoplastic polymeric resin pellets are externally coated with the aqueous solution.

16 . A cleaning mixture, comprising:
water; thermoplastic polymeric resin pellets having a Rockwell R hardness of from 85 to 140 as measured by ASTM D785; and a surfactant salt comprises at least one of the following: sulfonate salts, C 6 to C 36 carboxylic acid salts, and mixtures thereof; wherein the cleaning mixture has a pH from 6.0 to 9.0; wherein the surfactant salt and the water form an aqueous solution and the aqueous solution has a viscosity of 20 to 1,000 centipoise as measured by ASTM D445 at 23° C.; and wherein the thermoplastic polymeric resin pellets comprise cylinders with an average length of 2.0 to 6.0 mm and an average diameter of 0.5 to 4.0 mm.

17 . The cleaning mixture of claim 14 , wherein the cleaning mixture consists of:
70 to 99 wt % of the thermoplastic polymeric resin pellets; and 1 to 30 wt % of an aqueous solution that contains 0.2 to 30 wt % of the surfactant.

18 . The cleaning mixture of claim 15 , wherein the surfactant salt comprises a C 6 to C 36 carboxylic acid salt.

19 . The cleaning mixture of claim 15 , wherein the surfactant salt and the water form an aqueous solution and wherein the thermoplastic polymeric resin pellets are externally coated with the aqueous solution.

Assignees

• Sabic Global Technologies Bv

Inventors

• Gallucci Robert Russell
• Ehrensbeck Franklin

Classifications

• B29C2948/9299

  Treatment of equipment, e.g. purging, cleaning, lubricating or filter exchange · CPC title

• C11D1/29

  Sulfates of polyoxyalkylene ethers · CPC title

• C11D3/37

  Polymers {(polymeric surface-active agents C11D1/008; polysaccharides C11D3/222)} · CPC title

• C11D3/3715

  Polyesters or polycarbonates · CPC title

• C11D3/3719

  Polyamides or polyimides · CPC title