Combined seals, compositions, and methods of making the same
A combined sealing member is provided that includes a composition comprising two or more polyolefin elastomers selected from the group consisting of a dense, a micro-dense and a dynamic silane-crosslinked polyolefin elastomer having a respective density of less than 0.90 g/cm 3 , less than 0.70 g/cm 3 , and less than 0.60 g/cm 3 . The combined sealing member exhibits a compression set of from about 5.0% to about 35.0%, as measured according to ASTM D 395 (22 hrs @ 70° C.).
1. A combined sealing member comprising: a composition comprising two or more polyolefin elastomers selected from the group consisting of
a dense silane-crosslinked polyolefin elastomer having a density of less than 0.90 g/cm 3 , a tensile strength ranging from 10.4 to about 14.5 MPa as measured according to ASTM D412, a Shore A hardness ranging from about 76 to about 88 as measured according to ASTM D412, and a crystallinity of from about 5% to about 15%, wherein from about 1 wt % to about 20 wt % of the dense silane-crosslinked polyolefin elastomer is a polypropylene filler having a crystallinity greater than 40%,
a microdense silane-crosslinked polyolefin elastomer having a density of less than 0.70 g/cm 3 , a tensile strength ranging from about 5.0 to about 8.7 MPa as measured according to ASTM D412, a Shore A hardness ranging from 60 to 87 as measured according to ASTM D412, and a crystallinity of from about 5% to about 15%, wherein from about 1 wt % to about 20 wt % of the microdense silane-crosslinked polyolefin elastomer is a polypropylene filler having a crystallinity greater than 40%, and
a dynamic silane-crosslinked polyolefin elastomer having a density of less than 0.60 g/cm 3 , a tensile strength ranging from about 2.0 to about 2.9 MPa as measured according to ASTM D412 and a crystallinity of from about 5% to about 15%,
wherein the polyolefin elastomers do not display a Mullins effect or a Payne effect,
wherein the combined sealing member and the foamed silane-crosslinked polyolefin elastomers are thermosets, and
wherein the combined sealing member exhibits a compression set of from about 5.0% to about 35.0%, as measured according to ASTM D 395 (22 hrs @ 70° C.).
2. The combined sealing member of claim 1 , wherein the compression set is from about 15.0% to about 35.0%, as measured according to ASTM D 395 (22 hrs @ 70° C.).
3. The combined sealing member of claim 1 , wherein the two or more polyolefin elastomers are selected from the group consisting of
a dense silane-crosslinked polyolefin elastomer having a density of about 0.80 g/cm 3 to about 0.89 g/cm 3 ,
a microdense silane-crosslinked polyolefin elastomer having a density of about 0.40 g/cm 3 to about 0.59 g/cm 3 , and
a dynamic silane-crosslinked polyolefin elastomer having a density of about 0.40 g/cm 3 to about 0.59 g/cm 3 .
4. The combined sealing member of claim 1 , wherein the silane-crosslinked polyolefin elastomers exhibit crystallinities of from about 5% to about 10%.
5. The combined sealing member of claim 1 , wherein the silane-crosslinked polyolefin elastomers exhibit glass transition temperatures of from about −75° C. to about −25° C.
6. The combined sealing member of claim 1 , wherein the sealing member exhibits a weathering color difference of from about 0.25 ΔE to about 2.0 ΔE, as measured according to ASTM D2244.
7. The combined sealing member of claim 1 , further comprising:
a coloring agent.
8. A combined sealing member comprising:
comprising a first and a second polyolefin elastomer,
wherein the first elastomer comprises a microdense silane-crosslinked polyolefin elastomer having a density of less than 0.70 g/cm 3 , a tensile strength ranging from about 5.0 to about 8.7 MPa as measured according to ASTM D412, and a Shore A hardness ranging from 60 to 87 as measured according to ASTM D412, and a crystallinity of from about 5% to about 15%, wherein from about 1 wt % to about 20 wt % of the microdense silane-crosslinked polyolefin elastomer is a polypropylene filler having a crystallinity greater than 40%, and
wherein the second elastomer comprises
a dense silane-crosslinked polyolefin elastomer having a density of less than 0.90 g/cm 3 , a tensile strength ranging from 10.4 to about 14.5 MPa as measured according to ASTM D412, a Shore A hardness ranging from about 76 to about 88 as measured according to ASTM D412, and a crystallinity of from about 5% to about 15%, wherein from about 1 wt % to about 20 wt % of the dense silane-crosslinked polyolefin elastomer is a polypropylene filler having a crystallinity greater than 40%, or
a dynamic silane-crosslinked polyolefin elastomer having a density of less than 0.60 g/cm 3 , a tensile strength ranging from about 2.0 to about 2.9 MPa as measured according to ASTM D412, and a crystallinity of from about 5% to about 15%,
wherein the polyolefin elastomers do not display a Mullins effect or a Payne effect,
wherein the combined sealing member and the foamed silane-crosslinked polyolefin elastomers are thermosets, and
wherein the combined sealing member exhibits a compression set of from about 5.0% to about 35.0%, as measured according to ASTM D 395 (22 hrs @ 70° C.).
9. The combined sealing member of claim 8 , wherein the compression set is from about 15.0% to about 35.0%, as measured according to ASTM D 395 (22 hrs @ 70° C.).
10. The combined sealing member of claim 8 , wherein
the first polyolefin elastomer is a microdense silane-crosslinked polyolefin elastomer having a density of about 0.40 g/cm 3 to about 0.59 g/cm 3 and
the second polyolefin elastomer comprises a dense silane-crosslinked polyolefin elastomer having a density of about 0.80 g/cm 3 to about 0.89 g/cm 3 , or a dynamic silane-crosslinked polyolefin elastomer having a density of about 0.40 g/cm 3 to about 0.59 g/cm 3 .
11. The combined sealing member of claim 8 , wherein the silane-crosslinked polyolefin elastomers exhibit crystallinities of from about 5% to about 10%.
12. The combined sealing member of claim 8 , wherein the silane-crosslinked polyolefin elastomers exhibit glass transition temperatures of from about −75° C. to about −25° C.
13. A combined sealing member comprising:
a dense silane-crosslinked polyolefin elastomer having a density of less than 0.90 g/cm 3 , a tensile strength ranging from 10.4 to about 14.5 MPa as measured according to ASTM D412, a Shore A hardness ranging from about 76 to about 88 as measured according to ASTM D412, and a crystallinity of from about 5% to about 15%, wherein from about 1 wt % to about 20 wt % of the dense silane-crosslinked polyolefin elastomer is a polypropylene filler having a crystallinity greater than 40%, and
a dynamic silane-crosslinked polyolefin elastomer having a density of less than 0.60 g/cm 3 , a tensile strength ranging from about 2.0 to about 2.9 MPa as measured according to ASTM D412 and a crystallinity of from about 5% to about 15%,
wherein the polyolefin elastomers do not display a Mullins effect or a Payne effect,
wherein the combined sealing member and the foamed silane-crosslinked polyolefin elastomers are thermosets, and
wherein the combined sealing member exhibits a compression set of from about 5.0% to about 35.0%, as measured according to ASTM D 395 (22 hrs @ 70° C.).
14. The combined sealing member of claim 13 , wherein the compression set is from about 15.0% to about 35.0%, as measured according to ASTM D 395 (22 hrs @ 70° C.).
15. The combined sealing member of claim 13 , wherein the dense silane-crosslinked polyolefin elastomer has a density of about 0.80 g/cm 3 to about 0.89 g/cm 3 , and the dynamic silane-crosslinked polyolefin elastomer has a density of about 0.40 g/cm 3 to about 0.59 g/cm 3 .
16. The combined sealing member of claim 13 , wherein the silane-crosslinked polyolefin elastomers exhibit crystallinities of from about 5% to about 10%.
17. The combined sealing member of claim 13 , wherein the silane-crosslinked polyolefin elastomers exhibit glass transition temperatures of from about −75° C. to about −25° C.
18. The combined sealing member of claim 13 , further comprising:
a coloring agent.