Propylene-based elastomers for roofing compositions and methods for preparing the same

Patent metadata

Field	Value
Publication number	US-9926443-B2
Application number	US-201615259750-A
Country	US
Kind code	B2
Filing date	Sep 8, 2016
Priority date	Nov 9, 2015
Publication date	Mar 27, 2018
Grant date	Mar 27, 2018

Abstract

Provided herein are membranes including a blend of a propylene-based elastomer and an ethylene copolymer, a thermoplastic resin, a flame retardant, and an ultraviolet stabilizer.

First claim

We claim:

1. A reactor blend composition comprising:
(a) from about 70 wt % to about 95 wt % of a propylene-based elastomer,
wherein the propylene-based elastomer has an ethylene content of about 15 wt % to about 30 wt % based upon the weight of the propylene-based elastomer, and
(b) from about 5 wt % to about 30 wt % of an ethylene copolymer, where the ethylene-copolymer has an ethylene content of greater than or equal to about 70 wt % based upon the weight of the ethylene copolymer.

2. The composition of claim 1 , wherein the propylene-based elastomer has an ethylene content of about 16 wt % to about 18 wt %, a melting temperature of less than 120° C., and a heat of fusion less than 75 J/g.

3. A membrane composition comprising:
(a) from about 20 wt % to about 50 wt % of a polymer blend, comprising:
(i) from about 70 wt % to about 95 wt % of a propylene-based elastomer, wherein the propylene-based elastomer has an ethylene content of about 15 wt % to about 30 wt % based upon the weight of the propylene-based elastomer, and (ii) from about 5 wt % to about 30 wt % of an ethylene copolymer, where the ethylene-copolymer has an ethylene content of greater than or equal to about 70 wt % based upon the weight of the ethylene copolymer;

(b) from about 5 wt % to about 30 wt % of a thermoplastic resin based on the composition;
(c) at least one flame retardant; and
(d) at least one ultraviolet stabilizer.

4. The membrane of claim 3 , wherein the polymer blend is a reactor blend of the propylene-based elastomer and the ethylene copolymer.

5. The membrane of claim 3 , wherein the polymer blend is a physical blend of the propylene-based elastomer and the ethylene copolymer.

6. The membrane of claim 3 , wherein the thermoplastic resin is a propylene homopolymer.

7. The membrane of claim 6 , wherein the thermoplastic resin has a melt flow rate (230° C.; 2.16 kg) of greater than about 25 g/10 min.

8. The membrane of claim 3 , wherein the thermoplastic resin is a propylene impact copolymer.

9. The membrane of claim 8 , wherein the thermoplastic resin has a melt flow rate (230° C.; 2.16 kg) of less than about 5 g/10 min.

10. The membrane of claim 3 , wherein the propylene-based elastomer has an ethylene content of from 16 to 18 wt % based upon the weight of the propylene-based elastomer.

11. The membrane of claim 3 , wherein the thermoplastic resin is present in the composition in the amount of about 20 wt % to about 30 wt %.

12. The membrane of claim 3 , wherein the propylene-based elastomer has a melting temperature of less than 120° C. and a heat of fusion of less than 75 J/g.

13. The membrane of claim 3 , wherein the propylene-based polymer elastomer has an ethylene content of from 16 to 18 wt %, a melting temperature of less than 120° C., and a heat of fusion of less than 75 J/g.

14. The membrane of claim 3 , wherein the propylene-based elastomer is a reactor blend of a first polymer component and a second polymer component, wherein the first polymer component has an ethylene content R 1 of from greater than 5 to less than 30 wt % α-olefin, where the percentage by weight is based upon the total weight of the first polymer component, and wherein the second polymer component has an ethylene content R 2 of from greater than 1 to less than 10 wt % α-olefin, where the percentage by weight is based upon the total weight of the second polymer component.

15. The membrane of claim 14 , wherein the first polymer component has an α-olefin content R 1 of from 10 to 25 wt % α-olefin and the second polymer component has an α-olefin content R 2 of from greater than 2 to less than 8 wt % α-olefin.

16. The membrane of claim 3 , wherein the blend composition has at least three of the following properties:
(i) a storage modulus (E′) at −40° C. of less than 2.5×10 10 dynes/cm 2 ;
(ii) a storage modulus (E′) at −30° C. of less than 1.5×10 10 dynes/cm 2 ;
(iii) a storage modulus (E′) at −20° C. of less than 5×10 9 dynes/cm 2 ;
(iv) a storage modulus (E′) at 0° C. of less than 2×10 9 dynes/cm 2 ;
(v) a storage modulus (E′) at 20° C. of less than 1.5×10 9 dynes/cm 2 ;
(vi) a storage modulus (E′) at 40° C. of greater than 6.5×10 8 dynes/cm 2 ;
(vii) a storage modulus (E′) at 60° C. of greater than 4×10 8 dynes/cm 2 ;
(viii) a storage modulus (E′) at 80° C. of greater than 2×10 8 dynes/cm 2 ; or
(ix) a storage modulus (E′) at 100° C. of greater than 1×10 8 dynes/cm 2 .

17. The membrane of claim 3 , where the blend composition comprises from about 10 to about 30 wt % of the flame retardant, based on the weight of the blend composition.

18. The membrane of claim 3 , where the blend composition comprises from about 1 to about 20 wt % of the ultraviolet stabilizer, based on the weight of the blend composition.

19. A roofing composition comprising the membrane of claim 3 .

Assignees

• Exxonmobil Chemical Patents Inc

Inventors

• Li Liang
• Zacarias Felix M
• Dharmarajan Narayanaswami
• Kalfus Jan
• Brant Patrick

Classifications

• C08L2205/025

  containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure · CPC title

• C08L2207/04

  Thermoplastic elastomer · CPC title

• C08K3/26

  Carbonates; Bicarbonates · CPC title

• C08L23/12

  Polypropene · CPC title

• C08L2310/00

  Masterbatches · CPC title