Method for minimizing emissions while forming a polyurethane foam

Patent metadata

Field	Value
Publication number	US-9598605-B2
Application number	US-201414449497-A
Country	US
Kind code	B2
Filing date	Aug 1, 2014
Priority date	Sep 8, 2009
Publication date	Mar 21, 2017
Grant date	Mar 21, 2017

Abstract

A method minimizes emissions while spraying a mixture of a resin composition and a polyisocyanate onto a surface. The resin composition has a hydroxyl content of at least 400 mg KOH/g and includes a blowing agent that is a liquid under pressure, a first polyol, at least one additional polyol other than the first polyol, and optionally a catalyst, surfactant, and water. The mixture is sprayed onto the surface to form a polyurethane foam having a closed cell content of at least 90 percent. The mixture is also sprayed through a spray nozzle at a spray angle corresponding to a control spray angle of from 15 to 125 degrees measured at a pressure of from 10 to 40 psi using water as a standard. The step of spraying produces less than 50 parts of the polyisocyanate per one billion parts of air according to OSHA Method 47.

First claim

What is claimed is:

1. A polyurethane spraying system used to minimize emissions of a polyisocyanate while spraying a mixture of a polyisocyanate and a resin composition onto a surface, said system comprising:
A. a first reactant supply tank comprising the resin composition having a hydroxyl content of at least 400 mg potassium hydroxide per gram (KOH/g) and comprising:
(i) a blowing agent that is a liquid at room temperature under a pressure greater than atmospheric pressure;
(ii) a first polyol selected from the group of a Mannich polyol, an autocatalytic polyol, and combinations thereof;
(iii) at least one additional polyol other than the first polyol;
(iv) an optional catalyst;
(v) an optional surfactant, and
(vi) optionally water, wherein said resin composition has no other blowing agents;

B. a second reactant supply tank comprising the polyisocyanate;
C. a source of a gaseous propellant that is coupled with said first and second reactant supply tanks;
D. a mixing apparatus that is coupled with said first and second reactant supply tanks for mixing the resin composition and the polyisocyanate prior to spraying;
E. a spray nozzle that is coupled with said mixing apparatus and that produces less than 50 parts of the polyisocyanate per one billion parts of air according to Occupational Safety & Health Administration Method 47 while spraying the mixture onto the surface at a rate of 5 to 30 lbs/min to form a polyurethane foam having a closed cell content of at least 90 percent, said spray nozzle comprising:
(i) a nozzle body having a longitudinal axis, upstream and downstream ends opposite each other, and a passage defined by said nozzle body and in fluid communication with said upstream and downstream ends along said longitudinal axis for receiving the mixture; and
(ii) a circular spraying orifice having a radius of from 0.01 to 0.25 inches and defined by said nozzle body and disposed at said downstream end of said nozzle body transverse to said longitudinal axis for spraying the mixture at a spray angle corresponding to a control spray angle of from 15 to 125 degrees measured at a pressure of from 10 to 40 psi using water as a standard.

2. The polyurethane spraying system as set forth in claim 1 wherein said source of gaseous propellant is further defined as compressed gas.

3. The polyurethane spraying system as set forth in claim 1 wherein said mixing apparatus is coupled with said first and second reactant supply tanks via a connecting means that is heated to a temperature of from 75° F. to 90° F.

4. The polyurethane spraying system as set forth in claim 1 wherein the spray angle is further defined as corresponding to a control spray angle of from 15 to 120 degrees measured at a pressure of 40 psi using water as a standard, wherein the mixture is sprayed in a flat spray pattern that is substantially planar, and wherein the flat spray pattern has a spray width corresponding to a control spray width of from 2 to 30 inches measured at a distance of about 10 inches from the spray nozzle using water as the standard.

5. The polyurethane spraying system as set forth in claim 4 wherein the spray angle is further defined as corresponding to a control spray angle of 15, 25, 40, 50, 65, 80, 95, 110, or 120 degrees measured at a pressure of 40 psi using water as a standard.

6. The polyurethane spraying system as set forth in claim 1 wherein the spray angle is further defined as corresponding to a control spray angle of from 15 to 125 degrees measured at a pressure of 10 psi using water as a standard, wherein the mixture is sprayed in a conical spray pattern, and wherein the conical spray pattern has a spray width corresponding to a control spray width of from 2 to 30 inches at a distance of about 10 inches from the spray nozzle using water as the standard.

7. The polyurethane spraying system as set forth in claim 6 wherein the spray angle is further defined as corresponding to a control spray angle of from 50 to 80 degrees or of from 120 to 125 degrees, each measured at a pressure of 10 psi using water as a standard.

8. The polyurethane spraying system as set forth in claim 1 wherein said spray nozzle that is coupled with said mixing apparatus produces less than 5 parts of the isocyanate per one billion parts of air within a semicircle emanating from said surface and having a radius of 3 feet measured from said surface according to Occupational Safety & Health Administration Method 47.

9. The polyurethane spraying system as set forth in claim 1 wherein said blowing agent is further defined as hydrofluorocarbon 134 a.

10. A polyurethane spraying system as set forth in claim 1 wherein said surface is further defined as a wall of a building.

11. The polyurethane spraying system as set forth in claim 1 wherein said spray nozzle that is coupled with said mixing apparatus produces less than 3 parts of the isocyanate per one billion parts of air within a semicircle emanating from said surface and having a radius of 3 feet measured from said surface according to Occupational Safety & Health Administration Method 47.

12. The polyurethane spraying system as set forth in claim 1 wherein said source of gaseous propellant is further defined as compressed gas, wherein said mixing apparatus is coupled with said first and second reactant supply tanks via a connecting means that is heated to a temperature of from 75° F. to 90° F., wherein the spray angle is further defined as corresponding to a control spray angle of from 15 to 120 degrees measured at a pressure of 40 psi using water as a standard, wherein said mixture is sprayed in a flat spray pattern that is substantially planar, and wherein the flat spray pattern has a spray width corresponding to a control spray width of from 2 to 30 inches measured at a distance of about 10 inches from the spray nozzle using water as the standard.

13. The polyurethane spraying system as set forth in claim 1 wherein said source of gaseous propellant is further defined as compressed gas, wherein said mixing apparatus is coupled with said first and second reactant supply tanks via a connecting means that is heated to a temperature of from 75° F. to 90° F., wherein the spray angle is further defined as corresponding to a control spray angle of from 15, 25, 40, 50, 65, 80, 95, 110, or 120 degrees measured at a pressure of 40 psi using water as a standard, wherein said mixture is sprayed in a flat spray pattern that is substantially planar, and wherein the flat spray pattern has a spray width corresponding to a control spray width of from 2 to 30 inches measured at a distance of about 10 inches from the spray nozzle using water as the standard.

Assignees

• Basf Se

Inventors

• Ogonowski Joseph

Classifications

• B05C5/02

  {the liquid or other fluent material being discharged through an outlet orifice by pressure, e.g.} from an outlet device in contact or almost in contact, with the work · CPC title

• B05B7/1693

  with means for heating the material to be sprayed or an atomizing fluid in a supply hose or the like · CPC title

• C08J2375/04

  Polyurethanes · CPC title

• C08G18/4208

  containing aromatic groups · CPC title

• C09D175/08 Primary

  from polyethers · CPC title