Non-black rubber membranes

Patent metadata

Field	Value
Publication number	US-9309674-B2
Application number	US-201414446213-A
Country	US
Kind code	B2
Filing date	Jul 29, 2014
Priority date	Feb 19, 2008
Publication date	Apr 12, 2016
Grant date	Apr 12, 2016

Abstract

A roofing membrane comprising an olefinic rubber; and from about 20 to about 250 parts by weight of a silica filler per 100 parts by weight rubber; wherein the silica filler is chemically coupled to the olefinic rubber; and wherein the roofing membrane is non-black.

First claim

What is claimed is:

1. A process for preparing a roofing membrane, the method comprising:
i. mixing ethylene-propylene-diene rubber, silica, and a coupling agent defined by the formula:

where R 8 is a divalent organic group or a bond, R 9 is a halogen atom or an alkoxy group, and each R 10 is independently a halogen, an alkoxy group, or a monovalent organic group, and where R 11 is a blocking group to form a mixture, where the mixture is devoid of carbon black;
ii. adding a curative to the mixture to form a vulcanizable rubber composition;
iii. fabricating the vulcanizable composition into an uncured sheet; and
iv. curing the uncured sheet.

2. The process of claim 1 , further comprising the step of introducing ethylene-propylene-diene rubber with a coupling agent, where the coupling agent is dispersed in a carrier.

3. The process of claim 1 , where the curative is sulfur or a sulfur-containing compound.

4. The process of claim 3 , further comprising the step of adding a cure accelerator.

5. The process of claim 1 , where the coupling agent is a thioester, a thiophosphinate, a thiophosphate, or a thiosulphonate.

6. The process of claim 1 , where the mixture includes at least 30 and less than 120 parts by weight processing oil per 100 parts by weight rubber.

7. The process of claim 6 , where the processing oil has a sulfur content of less than 0.5 weight percent and an unsaturation level of less than 3%.

8. The process of claim 1 , where the vulcanizable composition includes:
i. an ethylene-propylene-diene rubber;
ii. from about 20 to about 250 parts by weight of a silica filler per 100 parts by weight rubber; and
iii. from about 0.1 to about 5 parts by weight of a silane coupling agent per 100 parts by weight rubber; wherein the silane coupling agent is compatible with both the ethylene-propylene-diene rubber and the silica filler such that the ethylene-propylene-diene rubber is chemically coupled to the silica filler.

Assignees

• Firestone Building Prod Co Llc
• Firestone Building Prod Co Llc

Inventors

• Wang Hao
• Davis James A
• Barham Willam F

Classifications

• B32B2307/5825

  Tear resistant · CPC title

• B32B2307/54

  Yield strength; Tensile strength · CPC title

• B32B2307/3065

  Flame resistant or retardant, fire resistant or retardant · CPC title

• B32B2264/10

  Inorganic particles · CPC title

• B32B2307/726

  Permeability to liquids, absorption · CPC title