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US4401792A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for increasing the rate of crystallization of polyesters

Assignee: General Electric Co
•
Filing: 1982-03-16
•
Granted: 1983-08-30
•
Expires: 2002-03-16
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Abstract

Abstract A process is provided for increasing the rate of crystallization of polyester compounds, such as poly (alkylene arylates), more particularly poly(alkylene terephthalates), or blends or mixtures thereof, as for example, poly(ethylene terephthalate), poly(butylene terephthalate) or mixtures of blends thereof, by incorporating therein a small amount of a polyethylene ionomer, or an alkali metal salt of benzoic acid, such as sodium benzoate. The faster crystallization rates improve injection molding performance of the polyesters and blends thereof, such as reduced post-mold shrinkage, faster mold cycle times and lower mold temperature. Also, the resultant products show increases in physical properties such as flex modulus, flex strength, deflection temperature under load (DTUL), tensile strength and solvent resistance. The process is applicable not only to unfilled polyester compounds but also to mineral or glass-filled, or fire-retardant-containing compounds, to impact modified polyesters, as well as blends of polyesters, such as poly(ethylene terephthalate)/poly(butylene terephthalate) (PET/PBT) blends, unfilled and filled with the aforesaid components.

Inventors

  • 👤 Robert J. Axelrod
  • 👤 Frank N. Liberti
  • 👤 John Semen

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 13:19
CPC Classifications
C; C08; C08K; C08K5/00; C08K5/04; C08K5/09; C08K5/098; C08L; C08L27/00; C08L27/02; C08L27/12; C08L33/00; C08L33/02; C08L35/00; C08L35/06; C08L67/00; C08L67/02

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 55 words
A process for increasing the rate of crystallization of (a) a polyester compound selected from the group consisting of a poly(butylene terephthalate) and a blend of poly(butylene terephthalate) and poly(ethylene terephthalate) which comprises incorporating therein (b) an alkali metal salt of benzoic acid in an amount sufficient to promote the rate of crystallization of (a).
Claim 2
Dependent Claim 55 words
A process for increasing the rate of crystallization of (a) a polyester compound selected from the group consisting of a poly(butylene terephthalate) and a blend of poly(butylene terephthalate) and poly(ethylene terephthalate) which comprises incorporating therein (b) an alkali metal salt of benzoic acid in an amount sufficient to promote the rate of crystallization of (a).
Claim 3
Dependent Claim 49 words
A process for increasing the rate of crystallization of a polyester compound selected from the group consisting of a poly(butylene terephthalate) and a blend of poly(butylene terephthalate) and poly(ethylene terephthalate) which comprises incorporating therein (b) an ionomer in an amount sufficient to promote the rate of crystallization of (a).
Claim 4
Dependent Claim 49 words
A process for increasing the rate of crystallization of a polyester compound selected from the group consisting of a poly(butylene terephthalate) and a blend of poly(butylene terephthalate) and poly(ethylene terephthalate) which comprises incorporating therein (b) an ionomer in an amount sufficient to promote the rate of crystallization of (a).
Claim 5
Dependent Claim 17 words
A process as described in either of claims 1 or 2, wherein the polyester is poly(butylene terephthalate).
Claim 6
Dependent Claim 23 words
A process as described in either of claims 1 or 2, wherein the polyester is a blend comprising poly(ethylene terephthalate) and poly(butylene terephthalate).
Claim 7
Dependent Claim 36 words
A process as described in either of claims 1 or 2, wherein the amount of (b) is from about 0.05% by weight to about 5.0% by weight based on the total weight of (a) and (b).
Claim 8
Dependent Claim 22 words
A process as described in claim 2, wherein (b) is an ionomer composed of acrylic acid, sodium acrylate and ethylene monomeric units.
Claim 9
Dependent Claim 15 words
A process as described in claim 1, wherein the alkali metal salt is sodium benzoate.
Claim 10
Dependent Claim 20 words
A process as described in either of claims 1 or 2, wherein (a) is filled with (c) a mineral filler.
Claim 11
Dependent Claim 15 words
A process as described in either of claims 1 or 2, wherein (a) is glass-filled.
Claim 12
Dependent Claim 14 words
A process as described in claim 9, wherein fibrous glass is predispersed in (a).
Claim 13
Dependent Claim 25 words
A process as described in either of claims 1 or 2, wherein (a) includes (d) a flame-retardant amount of a flame retardant agent or agents.
Claim 14
Dependent Claim 20 words
A process as described in claim 11, wherein (d) comprises an aromatic polycarbonate containing units of tetrabromobisphenol-A and antimony oxide.

References Cited (Backward Citations)

US2465319A Cited
US3047539A Cited
US3706699A Cited
US3591659A Cited
US3516957A Cited
GB1282679A Cited
US3761450A Cited
US3855277A Cited
US3953394B1 Cited
US3953394A Cited
US3833685A Cited
US4022748A Cited
US4044073A Cited
US4034013A Cited
US4090996A Cited
US4096202A Cited
US4096202B1 Cited
US4034016A Cited
US4257937A Cited
US4257937B1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-08-29 1987-02-28 1987-08-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-08-29 1991-02-28 1991-08-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-08-29 1995-02-28 1995-08-30 $7700.00 Window Closed / Lapsed

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