US4252915A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of blending ethylene vinylacetate copolymers and polydiorganosiloxane gums and the blends made by the method
Assignee: Dow Silicones Corp
•
Filing: 1979-01-31
•
Granted: 1981-02-24
•
Expires: 1999-01-31
Abstract
Abstract A processable, stable, homogeneous blend is obtained by mechanically mixing a polydiorganosiloxane gum containing 0.2 to less than 1.5 mol percent silicon atoms having vinyl or allyl groups with an ethylene vinylacetate copolymer containing 8 to 35 weight percent copolymerized vinylacetate. The polymers are mixed at a shear rate greater than 10 sec -1 , at a temperature between 170° C. and 235° C. and for a period of time sufficient to obtain at least 10 weight percent of the total blend of material which is insoluble in refluxing xylene.
Inventors
- 👤 Donald M. Bartos
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 09:57
CPC Classifications
H; H01; H01B; H01B3/00; H01B3/18; H01B3/30; H01B3/46; C; C08; C08L; C08L23/00; C08L23/02; C08L23/04; C08L23/08; C08L23/0846; C08L23/0853; C08L83/00; C08L83/04; C08L83/06; H01B3/44; H01B3/448; C08G; C08G77/00; C08G77/04; C08G77/20; C08G77/70; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31652; Y10T428/31663; Y10T428/31678; Y10T428/31692; Y10T428/31699
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
168 words
A method of blending a polydiorganosiloxane gum and an ethylene vinylacetate copolymer comprising mechanically mixing 10 to 175 parts by weight of a polydiorganosiloxane gum and 100 parts by weight of an ethylene vinylacetate copolymer at a temperature of 170° to 235° C., at a shear rate greater than 10 sec -1 and for a period of time sufficient to obtain at least 10 weight percent of the total blend of material which is insoluble in refluxing xylene, thereafter recovering a processable, stable homogeneous blend, the ethylene vinylacetate copolymer containing 8 to 35 weight percent copolymerized vinylacetate and the polydiorganosiloxane gum being a toluene soluble gum having a Williams plasticity greater than 0.020 inch, with a ratio of organic groups per silicon atom of about two wherein the organic groups are selected from methyl, phenyl, vinyl and allyl with from 0.2 to less than 1.5 mol percent of the silicon atoms having vinyl or allyl groups and no more than 50 percent of the organic groups being phenyl.
Claim 2
Independent Claim
168 words
A method of blending a polydiorganosiloxane gum and an ethylene vinylacetate copolymer comprising mechanically mixing 10 to 175 parts by weight of a polydiorganosiloxane gum and 100 parts by weight of an ethylene vinylacetate copolymer at a temperature of 170° to 235° C., at a shear rate greater than 10 sec -1 and for a period of time sufficient to obtain at least 10 weight percent of the total blend of material which is insoluble in refluxing xylene, thereafter recovering a processable, stable homogeneous blend, the ethylene vinylacetate copolymer containing 8 to 35 weight percent copolymerized vinylacetate and the polydiorganosiloxane gum being a toluene soluble gum having a Williams plasticity greater than 0.020 inch, with a ratio of organic groups per silicon atom of about two wherein the organic groups are selected from methyl, phenyl, vinyl and allyl with from 0.2 to less than 1.5 mol percent of the silicon atoms having vinyl or allyl groups and no more than 50 percent of the organic groups being phenyl.
Claim 3
Dependent Claim
12 words
The processable, stable, homogeneous blend prepared by the method of claim 1.
Claim 4
Dependent Claim
30 words
The method in accordance with claim 1 in which 100 to 160 parts by weight of the polydiorganosiloxane is mixed with 100 parts by weight of the ethylene vinylacetate copolymer.
Claim 5
Dependent Claim
23 words
The method in accordance with claim 1 or 3 in which the ethylene vinylacetate copolymer contains 15 to 30 weight percent copolymerized vinylacetate.
Claim 6
Dependent Claim
26 words
The method in accordance with claim 4 in which the polydiorganosiloxane gum contains 0.2 to 1.0 mol percent of silicon atoms having vinyl or allyl groups.
Claim 7
Dependent Claim
12 words
The processable, stable, homogeneous blend prepared by the method of claim 5.
References Cited (Backward Citations)
US2888424A
Cited
US2888419A
Cited
US2930083A
Cited
US3227777A
Cited
US3798185A
Cited
GB1294986A
Cited
US3865897A
Cited
US3975455A
Cited
US3979356A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-02-24 | 1984-08-25 | 1985-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-02-24 | 1988-08-25 | 1989-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-02-24 | 1992-08-25 | 1993-02-24 | $7700.00 | Window Closed / Lapsed |