Patent US2518125A successfully refreshed from Google Patents.
US4489034A
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US
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Thermoforming process using modified polymer blend
Assignee: Union Carbide Chemicals and Plastics Technology LLC
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Filing: 1982-08-25
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Granted: 1984-12-18
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Expires: 2002-08-25
Abstract
Abstract An improved thermoforming process comprises the use of crystalline polymer sheets prepared by the peroxide reacting of the mixture of a poly(alpha olefin) selected from polypropylene and polybutylene plus a polyethylene.
Inventors
- 👤 Sol Davison
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 16:02
CPC Classifications
C; C08; C08L; C08L23/00; C08L23/02; C08L23/10; C08L23/12; B; B29; B29C; B29C48/00; B29C48/022; B29C51/00; B29C51/002; C08K; C08K5/00; C08K5/04; C08K5/14; C08L23/04; C08L23/06; C08L23/18; C08L23/20; C08L9/00; B29C48/001; B29C48/0017; B29C48/0022; B29C48/03; B29C48/07; B29C48/08; B29K; B29K2023/00; B29K2101/00; B29K2101/10; B29K2105/00; B29K2105/24; B29L; B29L2007/00; B29L2007/008
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
100 words
In a process for manufacturing molded articles by thermoforming crystalline polymer sheets, the improvement wherein said sheets are extruded from a polymer composition prepared by the peroxide reacting of the mixture of: (a) 65 to 95 percent by weight of a mixture of about 50 to about 96 percent by weight of a crystalline isotactic poly(alpha-olefin) selected from the group consisting of polypropylene and polybutylene and about 50 to about 4 percent by weight of a polyethylene; (b) 5 to 35 percent by weight of an impact modifier; and (c) an effective amount of a 1,2 polybutadiene crosslinking efficiency improver.
Claim 2
Dependent Claim
100 words
In a process for manufacturing molded articles by thermoforming crystalline polymer sheets, the improvement wherein said sheets are extruded from a polymer composition prepared by the peroxide reacting of the mixture of: (a) 65 to 95 percent by weight of a mixture of about 50 to about 96 percent by weight of a crystalline isotactic poly(alpha-olefin) selected from the group consisting of polypropylene and polybutylene and about 50 to about 4 percent by weight of a polyethylene; (b) 5 to 35 percent by weight of an impact modifier; and (c) an effective amount of a 1,2 polybutadiene crosslinking efficiency improver.
Claim 3
Dependent Claim
12 words
The process according to claim 1 wherein said poly(alpha olefin) is polypropylene.
Claim 4
Dependent Claim
11 words
The process according to claim 1 wherein said poly(alpha-olefin) is polybutylene.
Claim 5
Dependent Claim
13 words
The process according to claim 1 wherein said polyethylene is high density polyethylene.
Claim 6
Dependent Claim
28 words
The process according to claim 1 wherein said sheets are thermoformed at a temperature between the melting point of said poly(alpha-olefin) and 60° C. above said melting point.
Claim 7
Dependent Claim
33 words
The process according to claim 1 wherein said thermoforming process comprises mechanical stamping of said sheets at a temperature between the melting point of said poly(alpha-olefin) and 40° C. above said melting point.
Claim 8
Dependent Claim
35 words
The process according to claim 1 wherein said mixture of step (a) comprises between about 90 weight percent and about 60 weight percent poly(alpha-olefin) and between about 10 weight percent and 40 weight percent polyethylene.
Claim 9
Dependent Claim
55 words
The process according to claim 1 wherein said peroxide reacting comprises contacting the mixture of said poly(alpha-olefin), said polyethylene, said impact modifier and said crosslinking efficiency improver in an extruder in the presence of between about 150 and about 1,000 ppmw of a peroxide at a temperature of between about 190 and about 250° C.
Claim 10
Dependent Claim
11 words
The process according to claim 8 wherein said peroxide is 2,5-dimethyl-2,5-di(t-butylperoxy)hexane.
Claim 11
Dependent Claim
34 words
The process of claim 1 wherein said impact modifier is selected from the group consisting of: (i) a blend of a polyethylene and an ethylene-propylene rubber; and (ii) a selectivity hydrogenated styrene-butadiene-styrene block copolymer.
Claim 12
Dependent Claim
19 words
The process of claim 1 wherein said impact modifier is a blend of a polyethylene and an ethylene-propylene rubber.
Claim 13
Dependent Claim
112 words
A product obtained by contacting the mixture of: (a) 95 to 65 percent by weight of a mixture of about 50 to about 96 percent by weight of a crystalline isotactic poly(alpha-olefin) selected from the group consisting of polypropylene and polybutylene and about 50 to about 4 percent by weight of a polyethylene; (b) 5 to 35 percent by weight of an impact modifier; and (c) an effective amount of 1,2 polybutadiene crosslinking efficiency improver in an extruder in the presence of about 150 to about 1000 ppmw (based on the total polymer content of said mixture) of a peroxide at a temperature of between about 110° C. and about 250° C.
Claim 14
Dependent Claim
112 words
A product obtained by contacting the mixture of: (a) 95 to 65 percent by weight of a mixture of about 50 to about 96 percent by weight of a crystalline isotactic poly(alpha-olefin) selected from the group consisting of polypropylene and polybutylene and about 50 to about 4 percent by weight of a polyethylene; (b) 5 to 35 percent by weight of an impact modifier; and (c) an effective amount of 1,2 polybutadiene crosslinking efficiency improver in an extruder in the presence of about 150 to about 1000 ppmw (based on the total polymer content of said mixture) of a peroxide at a temperature of between about 110° C. and about 250° C.
Claim 15
Dependent Claim
10 words
The product of claim 12 wherein said peroxide is 2,5-dimethyl-2,5-di(t-butylperoxy)hexane.
Claim 16
Dependent Claim
31 words
The product of claim 12 wherein said crosslinking efficiency improver is added to improve crosslinking of the polyethylene and impact improver masterbatch, relative to the cracking of the polypropylene or polybutylene.
Claim 17
Dependent Claim
14 words
The product of claim 12 wherein said crystalline isotactic poly(alpha-olefin) is a propylene copolymer.
Claim 18
Dependent Claim
14 words
The product of claim 13 wherein said crystalline isotactic poly(alpha-olefin) is an impact polypropylene.
Claim 19
Dependent Claim
12 words
The product of claim 12 wherein said polyethylene is high density polyethylene.
Claim 20
Dependent Claim
34 words
The product of claim 12 wherein said impact modifier is selected from the group consisting of: (i) a blend of a polyethylene and an ethylene-propylene rubber; and (ii) a selectively hydrogenated styrene-butadiene-styrene block copolymer.
Claim 21
Dependent Claim
19 words
The product of claim 12 wherein said impact modifier is a blend of a polyethylene and an ethylene-propylene rubber.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-12-18 | 1988-06-18 | 1988-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-18 | 1992-06-18 | 1992-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-18 | 1996-06-18 | 1996-12-18 | $7700.00 | Window Closed / Lapsed |