Active polymer modification of bitumen for use in roofing materials

Patent metadata

Field	Value
Publication number	US-11021609-B2
Application number	US-201916245684-A
Country	US
Kind code	B2
Filing date	Jan 11, 2019
Priority date	Feb 26, 2014
Publication date	Jun 1, 2021
Grant date	Jun 1, 2021

Abstract

A modified bitumen consisting of a polyurethane wherein the polyisocyanate or polyisocyanate-dominated polyurethane prepolymer (or prepolymers) is first reacted with the bitumen to take advantage of the bitumen's hydroxyl and amine functionality and form an isocyanate-bitumen adduct to form a weatherproofing product.

First claim

What is claimed:

1. An actively modified polymer-modified bitumen formulation comprising:
25-75 wt. % of a first component that consists of bitumen, coal tar, or combinations thereof;
1-49 wt. % of a second component that consists of polyurethane, or blend of polyurethane and rubber, said polyurethane including isocyanate end groups, said polyurethane formed from a polyisocyanate compound and a polyol, said polyol includes a molecular weight compound of 1000-5000 molecular weight, a content of said polyol creating a NCO/OH equivalent ratio of 2:1 to 7:1 in said bitumen formulation; and,
1-66 wt. % of a filler;
wherein a weight percent of said first component is greater than a weight percent of said second component, said isocyanate end groups in said polyurethane formulated to be reactable with hydroxyl end groups in said bitumen, said coal tar, or combinations thereof, said formulation can be used to create a membrane having improved mineral retention and weatherability.

2. The formulation as defined in claim 1 , wherein said polyol includes at least one compound selected from the group consisting of propylene glycol, polycarbonate diol, polybutadiene glycols and polybutadiene polyols.

3. The formulation as defined in claim 1 , wherein said polyol includes at least two compounds selected from the group consisting of propylene glycol, polycarbonate diol, polybutadiene glycols and polybutadiene polyols.

4. The formulation as defined in claim 1 , wherein said polyol includes at least three compounds selected from the group consisting of propylene glycol, polycarbonate diol, polybutadiene glycols and polybutadiene polyols.

5. The formulation as defined in claim 3 , wherein said polyol includes two different types of compounds selected from the group consisting of propylene glycol and polycarbonate diol.

6. The formulation as defined in claim 4 , wherein said polyol includes two different types of compounds selected from the group consisting of propylene glycol and polycarbonate diol.

7. The formulation as defined in claim 1 , wherein said NCO/OH equivalent ratio is 3:1 to 6:1.

8. The formulation as defined in claim 1 , wherein said filler includes at least one compound selected from the group consisting of potassium polyphosphate, calcium carbonate, ammonium polyphosphate, alumina trihydrate and Mg(OH) 2 .

9. The formulation as defined in claim 8 , wherein said filler includes three or more compounds selected from the group consisting of calcium carbonate, ammonium polyphosphate, alumina trihydrate and potassium polyphosphate.

10. The formulation as defined in claim 8 , wherein said filler includes calcium carbonate, ammonium polyphosphate, and alumina trihydrate.

11. The formulation as defined in claim 8 , wherein said filler includes calcium carbonate, ammonium polyphosphate, and alumina trihydrate, a content of said calcium carbonate is 5-40 wt. %, a content of said ammonium polyphosphate is 0.1-5 wt. %, a content of said alumina trihydrate is 0.5-20 wt. %.

12. The formulation as defined in claim 1 , wherein said second component includes both said polyurethane and said rubber, said rubber including one or more compounds selected from the group consisting of SBS, SEBS, SIS, and nitrile rubber, a weight ratio of said rubber to said polyurethane is 1:0.2 to 1:15.

13. The formulation as defined in claim 1 , wherein said first component includes a blend of said coal tar and said bitumen, a weight ratio of said coal tar and said bitumen 1:0.1 to 1:10.

14. The formulation as defined in claim 1 , further including two or more additional components selected from the group consisting of processing oil, chain extender, modifier, antioxidant, and catalyst, said additional components having a weight percent of 10-66.

15. The formulation as defined in claim 1 , wherein said polyol includes both diols and triols, a weight ratio of said diols to said triols is about 1:1 to 5:1.

16. The formulation as defined in claim 1 , wherein said polyurethane includes at least one chain extender.

17. The formulation as defined in claim 1 , wherein said chain extender includes one or more compounds selected from the group consisting of propylene glycol, ethylene glycol, 1,3-butanediol, and dipropylene glycol.

18. The formulation as defined in claim 1 , wherein said polyol includes a molecular weight compound of 1000-3000.

19. The formulation as defined in claim 1 , comprising by weight percent:

Bitumen and/or coal tar
30-70

Polyurethane
  4-20%

Filler
 10-66.

20. The formulation as defined in claim 1 , comprising by weight percent:

Bitumen and/or coal tar
50-55

Polyurethane
 8-20

Filler
30-41.

21. The formulation as defined in claim 1 , comprising by weight percent:

Bitumen and/or coal tar
50-55

Polyurethane
 8-20

Filler
30-41

Process oil
 1-5.

22. The formulation as defined in claim 1 , comprising by weight percent:

Bitumen and/or coal tar
50-55

Polyurethane
 8-20

Filler
30-41

Process oil
 1-3.

Assignees

• Garland Ind Inc

Inventors

• Smith Jason D
• Mellott Ii Joseph W
• Rus Melissa
• Sokol David
• Holland Julia

Classifications

• C08L95/00 Primary

  Compositions of bituminous materials, e.g. asphalt, tar, pitch · CPC title

• C08L2555/74

  Petrochemicals other than waxes, e.g. synthetic oils, diesel or other fuels, hydrocarbons, halogenated or otherwise functionalized hydrocarbons · CPC title

• C08G18/69

  Polymers of conjugated dienes {(hydrogenated polymers of conjugated dienes C08G18/6208)} · CPC title

• C08G18/44

  Polycarbonates · CPC title

• C08L2555/50

  Inorganic non-macromolecular ingredients · CPC title