US4752428A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Injection molding process with reactive gas treatment
Assignee: Air Products and Chemicals Inc
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Filing: 1987-01-28
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Granted: 1988-06-21
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Expires: 2007-01-28
Abstract
Abstract The present invention is a process for making shaped articles by injecting a thermoplastic or thermoset polymer into a mold cavity in which is maintained at atmosphere containing between 0.1 mole % and 50 mole % F 2 and at least 20 ppm O 2 while said polymer is being injected into the mold. The process results in shaped articles having altered physical and chemical characteristics. A weld line formed where two interfaces of the polymer are joined in the mold cavity serves as a clean break point when pressure is applied to an article formed by the process. The atmosphere in the mold cavity may contain SO 3 .
Inventors
- 👤 Mark A. Williams
- 👤 Bernard D. Bauman
- 👤 David R. Ruprecht
- 👤 Paul D. Marsh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:27
CPC Classifications
B; B29; B29C; B29C45/00; C; C08; C08J; C08J5/00; C08J5/12; C08J5/124; B29C37/00; B29C37/0053; B29C37/0057; B29C45/17; B29C45/1701; B29C2791/00; B29C2791/004; B29C2791/005; C08J2323/00; C08J2323/02; C08J2323/10; C08J2323/12
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
118 words
In a process for making shaped articles by injecting a plasticized thermoplastic or thermoset polymer into a mold cavity, the improvement for altering the physical and chemical characteristics of the resulting article which comprises: maintaining in said mold cavity an atmosphere containing between 0.1 mole % and 50 mole % F 2 and at least 20 ppm O 2 while said polymer is being injected into the mold cavity, and forming a weld line where two interfaces of the plasticized polymer are joined in the mold cavity; the physical and chemical characteristics of the resulting article being altered such that said weld line is capable of forming a clean break point when pressure is applied to the article.
Claim 2
Dependent Claim
118 words
In a process for making shaped articles by injecting a plasticized thermoplastic or thermoset polymer into a mold cavity, the improvement for altering the physical and chemical characteristics of the resulting article which comprises: maintaining in said mold cavity an atmosphere containing between 0.1 mole % and 50 mole % F 2 and at least 20 ppm O 2 while said polymer is being injected into the mold cavity, and forming a weld line where two interfaces of the plasticized polymer are joined in the mold cavity; the physical and chemical characteristics of the resulting article being altered such that said weld line is capable of forming a clean break point when pressure is applied to the article.
Claim 3
Dependent Claim
26 words
A process in accordance with claim 1 wherein said atmosphere in the mold cavity contains between 2 mole % and 10 mole % F 2 .
Claim 4
Dependent Claim
21 words
A process in accordance with claim 1 wherein the balance of the atmosphere in the mold cavity is inert gaseous components.
Claim 5
Dependent Claim
19 words
A process in accordance with claim 1 wherein the balance of the atmosphere in the mold cavity is air.
Claim 6
Dependent Claim
16 words
A process in accordance with claim 1 wherein the thermoplastic or thermoset polymer is a polyolefin.
Claim 7
Dependent Claim
21 words
A process in accordance with claim 1 wherein the pressure within the mold cavity is maintained between 20 and 60 psig.
Claim 8
Dependent Claim
22 words
A process in accordance with claim 1 wherein said atmosphere in the mold cavity contains at least 100 ppm O 2 .
Claim 9
Dependent Claim
135 words
A process for injection molding an article from a plasticized thermoplastic or thermoset polymer such that the resulting article has altered physical and chemical properties, said process comprising: (a) evacuating or displacing air or other gas from the cavity of a mold; (b) introducing a reactive gas containing between 0.1 mole % and 50 mole % F 2 into the mold cavity; (c) plasticizing the thermoplastic polymer or blending the thermoset polymer; and (d) injecting the resultant polymer into the mold cavity containing the reactive gas, and forming a weld line where two interfaces of the plasticized polymer are joined in the mold cavity; the physical and chemical characteristics of the resulting article being altered such that said weld line is capable of forming a clean break point when pressure is applied to the article.
Claim 10
Dependent Claim
135 words
A process for injection molding an article from a plasticized thermoplastic or thermoset polymer such that the resulting article has altered physical and chemical properties, said process comprising: (a) evacuating or displacing air or other gas from the cavity of a mold; (b) introducing a reactive gas containing between 0.1 mole % and 50 mole % F 2 into the mold cavity; (c) plasticizing the thermoplastic polymer or blending the thermoset polymer; and (d) injecting the resultant polymer into the mold cavity containing the reactive gas, and forming a weld line where two interfaces of the plasticized polymer are joined in the mold cavity; the physical and chemical characteristics of the resulting article being altered such that said weld line is capable of forming a clean break point when pressure is applied to the article.
Claim 11
Dependent Claim
24 words
A process in accordance with claim 8 wherein said reactive gas contains between 2 mole % and 10 mole % F 2 in air.
Claim 12
Dependent Claim
13 words
A process in accordance with claim 8 wherein said polymer is a polyolefin.
Claim 13
Dependent Claim
20 words
A process in accordance with claim 8 wherein said mold cavity is pressurized to between 20 psig and 60 psig.
Claim 14
Dependent Claim
22 words
A process in accordance with claim 8 wherein the surface of said article has increased surface energy relative to an untreated article.
Claim 15
Dependent Claim
24 words
A process in accordance with claim 1 wherein the surface of said article has improved bonding and adhesion characteristics relative to an untreated article.
Claim 16
Dependent Claim
21 words
A process in accordance with claim 8 wherein said reactive gas also contains at least 20 ppm of O 2 .
Claim 17
Dependent Claim
107 words
In a process for making shaped articles by injecting a plasticized thermoplastic or thermoset polymer into a mold cavity, the improvement for altering the physical and chemical characteristics of the resulting article which comprises: maintaining in said mold cavity an atmosphere containing at least 0.1 mole % SO 3 while said polymer is being injected into the mold, and forming a weld line where two interfaces of the plasticized polymer are joined in the mold cavity; the physical and chemical characteristics of the resulting article being altered such that said weld line is capable of forming a clean break point when pressure is applied to the article.
Claim 18
Dependent Claim
107 words
In a process for making shaped articles by injecting a plasticized thermoplastic or thermoset polymer into a mold cavity, the improvement for altering the physical and chemical characteristics of the resulting article which comprises: maintaining in said mold cavity an atmosphere containing at least 0.1 mole % SO 3 while said polymer is being injected into the mold, and forming a weld line where two interfaces of the plasticized polymer are joined in the mold cavity; the physical and chemical characteristics of the resulting article being altered such that said weld line is capable of forming a clean break point when pressure is applied to the article.
Claim 19
Dependent Claim
30 words
A process in accordance with claim 15 wherein the atmosphere in the mold cavity contains between 0.1 mole %-50 mole % SO 3 and the balance being inert gaseous components.
Claim 20
Dependent Claim
21 words
A process in accordance with claim 15 wherein the pressure within the mold cavity is maintained between 20 and 60 psig.
References Cited (Backward Citations)
US2811468A
Cited
US3255099A
Cited
GB1169394A
Cited
US3555620A
Cited
US4009304A
Cited
US3862284A
Cited
US3988491A
Cited
US4020223A
Cited
US4412804A
Cited
US4435453A
Cited
US4548867A
Cited
JPS6019519A
Cited
US4550043A
Cited
JPS61152421A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-06-21 | 1991-12-21 | 1992-06-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-06-21 | 1995-12-21 | 1996-06-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-06-21 | 1999-12-21 | 2000-06-21 | $7700.00 | Window Closed / Lapsed |