Roofing compositions comprising linear low density polyethylene

Patent metadata

Field	Value
Publication number	US-10647839-B2
Application number	US-201816193797-A
Country	US
Kind code	B2
Filing date	Nov 16, 2018
Priority date	Nov 21, 2017
Publication date	May 12, 2020
Grant date	May 12, 2020

Abstract

Provided is a polymer blend composition comprising linear low density polyethylene, a propylene polymer generally having rubber dispersed therein, and a combination of a propylene copolymer and an ethylene copolymer. In one embodiment, there is provided a polymer blend composition comprising 20 to 65 weight percent of a propylene polymer having from 10-60% crystallinity, 30-60 weight percent of a linear low density polyethylene, and a combination of the propylene copolymer and the ethylene copolymer comprising the remainder of the composition.

First claim

What is claimed is:

1. A membrane composition comprising:
a) from about 40 wt % to 85 wt % of a polymer blend composition comprising:
(i) 20-65 wt % of a propylene polymer having from 10-60% crystallinity and rubber dispersed therein;
(ii) 30-60 wt % of a linear low density polyethylene; and
(iii) 5-20 wt % of a combination of a propylene copolymer and an ethylene copolymer;
b) at least one flame retardant;
c) at least one ultraviolet stabilizer; and
d) at least one pigment.

2. The membrane composition of claim 1 , wherein the flame retardant comprises 20-40 wt % of the composition.

3. The membrane composition of claim 1 , wherein the pigment comprises from 4 to 6 wt % of the composition.

4. The membrane composition of claim 1 , wherein the pigment comprises TiO 2 .

5. A roofing membrane comprising the membrane composition of claim 1 .

6. A roof comprising the roofing membrane of claim 5 .

7. A method of preparing a thermoplastic polyolefin film, the method comprising forming a thermoplastic polyolefin film from the composition of claim 1 .

8. The membrane composition of claim 1 , comprising calcium carbonate.

9. The membrane composition of claim 1 , wherein the flame retardant comprises calcium carbonate.

10. The membrane composition of claim 8 , wherein calcium carbonate comprises at least 25 wt % of the membrane composition.

11. The membrane composition of claim 1 , wherein the amount of flame retardant, ultraviolet stabilizer and pigment comprises at least 25 wt % of the membrane composition.

12. The membrane composition of claim 1 , wherein the amount of propylene copolymer in the combination (iii) of a propylene copolymer and an ethylene copolymer comprises from 30 to 70 wt % based on the weight of the combination of copolymers.

Assignees

• Johns Manville

Inventors

• Peng Lichih R
• Kortmeyer Jordan
• Wang Lance
• Asrar Jawed

Classifications

• C08J2323/12

  Polypropene · CPC title

• C08J2423/16

  Ethene-propene or ethene-propene-diene copolymers · CPC title

• C08L23/16

  Ethylene-propylene or ethylene-propylene-diene copolymers · CPC title

• C08J2423/12

  Polypropene · CPC title

• C08J5/18

  Manufacture of films or sheets · CPC title