Reclaimed asphalt composition and methods of making and using same

Patent metadata

Field	Value
Publication number	US-10793720-B2
Application number	US-201815926495-A
Country	US
Kind code	B2
Filing date	Mar 20, 2018
Priority date	Mar 20, 2017
Publication date	Oct 6, 2020
Grant date	Oct 6, 2020

Abstract

A method of forming a paving composition using reclaimed asphalt pavement (RAP) and/or reclaimed asphalt shingle (RAS) is provided. The method comprises: a) providing a rejuvenated asphalt binder consisting essentially of bitumen, a block copolymer and a bio-oil, wherein the rejuvenated asphalt binder has a rotational viscosity at 135° C. equal to or less than 1000 centipoise, an original G*/sin δ at 64° C. equal to or greater than 1 kPa where G* is the complex shear modulus and δ is the phase angle; a G*/sin δ at 64° C. equal to or greater than 2.2 kPa after aging in a Rolling Thin Film Oven (RTFO); b) providing a virgin asphalt; c) heating the virgin asphalt to 160-200° C.; d) providing a RAP and/or RAS; and e) mixing the heated virgin asphalt, RAP/RAS, and the rejuvenated asphalt binder under conditions suitable to form the paving composition.

First claim

What is claimed is:

1. A method of forming a paving composition comprising:
providing a rejuvenated asphalt binder consisting essentially of bitumen, a block copolymer composition and a bio-oil, wherein the rejuvenated asphalt binder has a rotational viscosity at 135° C. of equal to or less than 1000 centipoise, an original G*/sin δ at 64° C. of equal to or greater than 1 kPa where G* is the complex shear modulus and δ is the phase angle; and after aging in a Rolling Thin Film Oven (RTFO) a G*/sin δ at 64° C. of equal to or greater than 2.2 kPa and % recovery at 3.2 kPa of equal to or greater than 80%;
providing a virgin asphalt;
heating the virgin asphalt to a temperature from 160° C. to 200° C.;
providing a reclaimed asphalt pavement (RAP) and/or a reclaimed asphalt shingle (RAS);
mixing the heated virgin asphalt, RAP, and the rejuvenated asphalt binder under conditions suitable for the formation of the paving composition.

2. The method of claim 1 further comprising:
providing a virgin aggregate and mixing the virgin aggregate with the heated virgin asphalt, RAP and/or RAS, and the rejuvenated asphalt binder under conditions suitable for the formation of the paving composition.

3. The method of claim 1 further comprising:
providing a crosslinking agent and contacting the crosslinking agent with the rejuvenated asphalt binder to produce a crosslinked polymer/bitumen.

4. The method of claim 1 further comprising:
providing a crosslinking agent;
contacting the crosslinking agent with the rejuvenated asphalt binder forming a crosslinked bitumen/copolymer composition prior to mixing the rejuvenated asphalt binder with the virgin aggregate, the heated virgin asphalt, and RAP and/or RAS.

5. The method of claim 1 , wherein providing a rejuvenated asphalt binder comprises:
combining a mixture of bitumen and bio-oil forming a first mixture;
adding a block copolymer to the first mixture at a weight ratio of block copolymer to bio-oil ranging from 1:7 to 3:1 to form the rejuvenated asphalt binder.

6. The method of claim 1 , wherein providing a rejuvenated asphalt binder comprises:
combining a mixture of bitumen, bio-oil, and block copolymer at a weight ratio of block copolymer to bio-oil ranging from 1:7 to 3:1 to form the rejuvenated asphalt binder.

7. The method of claim 1 , wherein providing a rejuvenated asphalt binder comprises:
combining a mixture of bitumen, bio-oil, and block copolymer, wherein the bio-oil is present in an amount of 6 wt. % to 13.25 wt. % based on the total weight of the rejuvenated asphalt binder.

8. The method of claim 1 , wherein providing a rejuvenated asphalt binder comprises:
combining a mixture of bitumen, bio-oil, and block copolymer, wherein the bio-oil is present in an amount from 5 to 20 wt. % based on a combined amount of bio-oil and bitumen.

9. The method of claim 1 , wherein the block copolymer composition comprises:
a) a diblock copolymer comprising one block of a monoalkenyl arene and one block of a conjugated diene, wherein the diblock copolymer has a peak molecular weight from 30,000 g/mol to 78,000 g/mol and a vinyl content from 35 to 80 mol percent, based on the number of repeat monomer units in the conjugated diene block; and
b) a block copolymer comprising at least two blocks of monoalkenyl arene and at least one block of a conjugated diene, wherein the block copolymers b) comprises
(i) linear triblock copolymers having a peak molecular weight that is from 1.5 to 3.0 times the peak molecular weight of the diblock copolymer (a), and a vinyl content from 35 to 80 mol percent based on the number of repeat monomer units in the conjugated diene blocks;
(ii) multiarm coupled block copolymers having a peak molecular weight that is 1.5 to 9.0 times the peak molecular weight of the diblock copolymer (a), and a vinyl content from 35 to 80 mol percent based on the number of repeat monomer units in the conjugated diene blocks;

or mixtures thereof, and wherein the ratio of (i) to (ii) is greater than 1:1.

10. The method of claim 1 , wherein the bio-oil comprises principally functionalities derived from carboxylic acids including resin acids or C 8 -C 20 fatty acids and C 1 -C 18 alcohols.

11. The method of claim 1 , wherein the % recovery at 3.2 kPa of equal to or greater than 90%.

12. A rejuvenated asphalt binder for use in forming a paving composition containing a reclaimed asphalt pavement (RAP) and/or a reclaimed asphalt shingle (RAS),
wherein the binder consists essentially of a mixture of bitumen, bio-oil, and a block copolymer at a weight ratio of block copolymer to bio-oil ranging from 1:7 to 3:1,
wherein the block copolymer comprises
a) a diblock copolymer comprising one block of a monoalkenyl arene and one block of a conjugated diene; and
b) one or more block copolymers comprising at least two blocks of monoalkenyl arene and at least one block of conjugated diene;
and wherein the rejuvenated asphalt binder has
a rotational viscosity at 135° C. of equal to or less than 1000 centipoise, an original G*/sin δ at 64° C. of equal to or greater than 1 kPa, where G* is the complex shear modulus and δ is the phase angle,
and a G*/sin δ at 64° C. of equal to or greater than 2.2 kPa after aging in a Rolling Thin Film Oven (RTFO),
and % recovery at 3.2 kPa of equal to or greater than 80%.

13. The rejuvenated asphalt binder of claim 12 , wherein the % recovery at 3.2 kPa of equal to or greater than 90%.

14. The rejuvenated asphalt binder of claim 12 , wherein the bio-oil comprises principally functionalities derived from carboxylic acids including resin acids or C 8 -C 20 fatty acids and C 1 -C 18 alcohols.

15. The rejuvenated asphalt binder of claim 12 , wherein
the diblock copolymer has a peak molecular weight from 30,000 g/mol to 78,000 g/mol, and a vinyl content from 35 to 80 mol percent based on the number of repeat monomer units in the conjugated diene block; and
the one or more block copolymers component b) comprises
(i) linear triblock copolymers having a peak molecular weight that is from 1.5 to 3.0 times the peak molecular weight of the diblock copolymer (a) and a vinyl content from 35 to 80 mol percent based on the number of repeat monomer units in the conjugated diene block,
(ii) multiarm coupled block copolymers having a peak molecular weight that is 1.5 to 9.0 times the peak molecular weight of the diblock copolymer (a) and a vinyl content from 35 to 80 mol percent based on the number of repeat monomer units in the conjugated diene block,
or mixtures thereof, and wherein the ratio of (i) to (ii) is greater than 1:1.

16. The rejuvenated asphalt binder of claim 12 , wherein the rejuvenated asphalt binder is for use in a paving composition.

17. The rejuvenated asphalt binder of claim 12 , wherein the rejuvenated asphalt binder is for use in a paving composition which comprises from 30 to 65 wt. % based on the total weight of the paving composition, of a reclaimed asphalt pavement (RAP) and/or a reclaimed asphalt shingle (RAS).

18. The rejuvenated asphalt binder of claim 12 , wherein the rejuvenated asphalt binder is for use in a paving composition which comprises from 35-60 wt. % based on the total weight of the paving composition, of a virgin aggregate.

19. The rejuvenated asphalt binder of claim 12 , wherein the rejuvenated asphalt is cross-linked with a crosslinking agent forming a crosslinked bitumen/copolymer composition.

20. The rejuvenated asphalt binder of claim 19 , wherein the crosslinked rejuvenated bitumen/copolymer co

Assignees

• Kraton Polymers Us Llc

Inventors

• Puchalski Sebastian
• Kluttz Robert Q
• Lubbers Christopher Matthew

Classifications

• C08L2555/20

  Mixtures of bitumen and aggregate defined by their production temperatures, e.g. production of asphalt for road or pavement applications · CPC title

• C08L95/00

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

• C08L2555/52

  Aggregate, e.g. crushed stone, sand, gravel or cement · CPC title

• C08L2555/34

  Recycled or waste materials, e.g. reclaimed bitumen, asphalt, roads or pathways, recycled roof coverings or shingles, recycled aggregate, recycled tires, crumb rubber, glass or cullet, fly or fuel ash, or slag · CPC title

• C08G81/022

  containing sequences of polymers of conjugated dienes and of polymers of alkenyl aromatic compounds · CPC title