US3821158A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polymer composition
Assignee: BP Chemicals Ltd
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Filing: 1972-10-25
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Granted: 1974-06-28
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Expires: 1992-10-25
Abstract
Abstract Thermosetting moulding compositions comprising at least 50 percent of an inorganic filler, a high vinyl butadiene polymer, a free radical initiator and polyethylene in an amount less than 100 percent of the polymerisable material as shrink controller are described. The high vinyl butadiene polymer preferably contains 65 percent of 1,2-bonded units (i.e., units containing pendant vinyl groups) and can be used in conjunction with copolymerisable monomers. The polyethylene can be a homo- or copolymer and preferably has a density in the range 0.915 to 0.96. Low density or a mixture of low and high density polyethylene are particularly preferred. The compositions have low shrinkage on thermosetting and have good tensile strength in the thermoset state.
Inventors
- 👤 P Westermann
- 👤 S Fogg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:41
CPC Classifications
C; C08; C08L; C08L9/00; C08K; C08K3/00; C08K3/18; C08K3/24; C08K3/26; C08L23/00; C08L23/02; C08L23/04
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
22 words
A thermosetting moulding composition according to claim 1 wherein the high vinyl butadiene polymer contains at least 65 percent of 1,2-bonded units.
Claim 2
Dependent Claim
26 words
A thermosetting moulding composition according to claim 1 wherein the amount of filler present is at least 200 percent of the weight of the polymerisable component.
Claim 3
Dependent Claim
26 words
A thermosetting moulding composition according to claim 1 wherein the polymerisable component contains a monomer or monomers capable of copolymerising with the high vinyl butadiene polymer.
Claim 4
Dependent Claim
38 words
A thermosetting moulding composition according to claim 4 wherein the copolymerisable monomer or monomers are selected from styrene, vinyl toluene, diethyl fumarate, diethyl maleate, dibutyl fumarate, acrylamide, methyacrylamide, N,N''-methylenebisacrylamide, ethylene glycol dimethacrylate, allyl methacrylate and trimethylol propane trimethacrylate.
Claim 5
Dependent Claim
16 words
A thermosetting moulding composition according to claim 1 wherein the free radical initiator is dicumyl peroxide.
Claim 6
Dependent Claim
20 words
A thermosetting moulding composition according to claim 1 wherein the free radical initiator is 1,3 or 1,4-bis-(tertiarybutyl peroxy isopropyl) benzene.
Claim 7
Dependent Claim
26 words
A thermosetting moulding composition according to claim 1 wherein the polyethylene shrink controller is low density polyethylene having a density in the range 0.915 to 0.925.
Claim 8
Dependent Claim
32 words
A thermosetting moulding composition according to claim 1 wherein the polyethylene shrink controller is a mixture of low and high density polyethylene, the high density polyethylene having a minimum density of 0.94.
Claim 9
Dependent Claim
32 words
A thermosetting moulding composition according to claim 1 wherein the concentration of the polyethylene shrink controller is in the range 10 to 70 percent based on the weight of the polymerisable component.
Claim 10
Dependent Claim
110 words
A thermosetting moulding composition of reduced shrinkage properties as compared to a like composition free from a shrinkage control agent, which composition comprises at least 50 percent to at least 200 percent by weight of an inorganic filler, based on the weight of the polymerisable component, which latter comprises a high vinyl butadiene polymer, a free radical initiator and at least 5 percent based on the weight of the polymerisable component of a shrink controller which is an ethylene homopolymer or an ethylene copolymer containing at least 85 percent of copolymerized ethylene units in an amount not more than 100 percent by weigHt of the amount of the polymerisable component.
Claim 11
Dependent Claim
41 words
A thermosetting moulding composition according to claim 11 wherein the shrink controller is a mixture of polyethylene having a density in the range of 0.915 to 0.96 and polyethylene having a density above 0.94 in the ratio of 3:1 to 1:3.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-27 | 1977-12-27 | 1978-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-27 | 1981-12-27 | 1982-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-27 | 1985-12-27 | 1986-06-28 | $7700.00 | Window Closed / Lapsed |