Modified bituminous composition for roof membranes
First Claim
Patent Images
1. A roofing membrane having cold flexibility below about −
- 20°
C. and high flow resistance above about 110°
C., comprising a matrix-filled fibrous substrate and a filled elastomer-modified bituminous composition comprising about 10 to about 30 wt % of said composition of a mineral filler and a bituminous composition comprising bitumen and about 8 to 13 wt % of said bitumen of an elastomer having a conjugated diene structure cross-linked to an extent to permit a reduction of about 10 to 20 wt % in the amount of elastomer in the bituminous composition for the same low and high temperature properties or a concomitant improvement in low and high temperature properties at the same amount of elastomer.
1 Assignment
0 Petitions
Accused Products
Abstract
Roofing membranes are provided with both high stiffness at high temperature (greater than 110 ° C.) and good flexibility at low temperature (less than −20 ° C.). Bituminous compositions may be more effectively used in such membranes at lower elastomer concentration than currently practiced, using conventional cross-linking reagents to prepare the modified bituminous compositions with a range of viscosities that are readily processed as compared with conventional non-cross-linked systems.
-
Citations
12 Claims
-
1. A roofing membrane having cold flexibility below about −
- 20°
C. and high flow resistance above about 110°
C., comprising a matrix-filled fibrous substrate and a filled elastomer-modified bituminous composition comprising about 10 to about 30 wt % of said composition of a mineral filler and a bituminous composition comprising bitumen and about 8 to 13 wt % of said bitumen of an elastomer having a conjugated diene structure cross-linked to an extent to permit a reduction of about 10 to 20 wt % in the amount of elastomer in the bituminous composition for the same low and high temperature properties or a concomitant improvement in low and high temperature properties at the same amount of elastomer. - View Dependent Claims (2, 3, 4, 5)
- 20°
-
6. A method of forming a roofing membrane comprising a filled bituminous composition, which comprises:
-
(a) fully dispersing into bitumen an elastomer having a conjugated diene structure in an amount of about 8 to about 13 wt % of the bitumen, (b) dispersing a cross-linking reagent for said elastomer in a predetermined amount depending on the reagent used, (c) permitting said cross-linking reagent to cross-link said elastomer while minimizing the incorporation of air into the composition, (d) blending a mineral filler in an amount of about 10 to about 30 wt % of the composition to provide a filled bituminous composition, and (e) forming a roofing membrane from said filled bituminous composition having about 10 to 20 wt % less elastomer in the bitumen for the same low and high temperature properties or a concomitant improvement in low and high temperature properties for the same amount of elastomer. - View Dependent Claims (7, 8, 9, 10, 11, 12)
-
Specification