US4267310A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing spherical particles of crystalline polymers
Assignee: Hercules LLC
•
Filing: 1979-12-26
•
Granted: 1981-05-12
•
Expires: 1999-12-26
Abstract
Abstract A process for producing uniformly spherical particles of crystalline, normally solid condensation polymers is described. The process of this invention further provides high yields of hydrophobic, non-agglomerating particles in a useful size range directly, without the need for subsequent processing, and is carried out by forming a dispersion of small liquid particles of the crystalline polymer in certain aprotic liquids containing 0.1 to 20% by weight of the polymer of a water-insoluble block or graft copolymer having at least one polymeric component which is soluble in the aprotic liquid and at least one other polymeric component which is insoluble in the aprotic liquid and associates with the crystalline polymer, in a specified manner, cooling the dispersion with agitation until the liquid particles solidify and recovering the particles.
Inventors
- 👤 Leo M. Landoll
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 11:23
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/02; C08J3/09; C08J3/12; C08J3/16
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
213 words
A process for producing spherical particles having diameters ranging from about 1 to about 300 microns of polyester or polyamide crystalline, normally solid condensation-type polymers having a melt viscosity of at least 2000 poises at 20° C. above the crystalline melting point of the polymer and having a degree of crystallinity above 20%, which process comprises agitating under conditions of shear a fluid mixture of said polymer in an aprotic liquid which is a non-solvent for said polymer and which contains dissolved or dispersed therein from 0.1 to 20%, based on the weight of said polymer of a water-insoluble block or graft copolymer having a number average molecular weight above about 2000 and having at least one polymeric component which is soluble in the aprotic liquid and at least one other polymeric component of a different type which is insoluble in the aprotic liquid and associates with the condensation-type polymer, at a temperature above the crystalline melting point of the condensation-type polymer until a dispersion of liquid particles having a size within the range of about 1 to 3000 microns is formed, agitating the dispersion while cooling to a temperature below the crystalline melting point of the condensation-type polymer until the liquid particles solidify, and recovering the resulting particles from the aprotic liquid.
Claim 2
Dependent Claim
213 words
A process for producing spherical particles having diameters ranging from about 1 to about 300 microns of polyester or polyamide crystalline, normally solid condensation-type polymers having a melt viscosity of at least 2000 poises at 20° C. above the crystalline melting point of the polymer and having a degree of crystallinity above 20%, which process comprises agitating under conditions of shear a fluid mixture of said polymer in an aprotic liquid which is a non-solvent for said polymer and which contains dissolved or dispersed therein from 0.1 to 20%, based on the weight of said polymer of a water-insoluble block or graft copolymer having a number average molecular weight above about 2000 and having at least one polymeric component which is soluble in the aprotic liquid and at least one other polymeric component of a different type which is insoluble in the aprotic liquid and associates with the condensation-type polymer, at a temperature above the crystalline melting point of the condensation-type polymer until a dispersion of liquid particles having a size within the range of about 1 to 3000 microns is formed, agitating the dispersion while cooling to a temperature below the crystalline melting point of the condensation-type polymer until the liquid particles solidify, and recovering the resulting particles from the aprotic liquid.
Claim 3
Dependent Claim
13 words
The process of claim 1 wherein the crystalline condensation-type polymer is a polyester.
Claim 4
Dependent Claim
12 words
The process of claim 2 wherein the polyester is an aliphatic polyester.
Claim 5
Dependent Claim
10 words
The process of claim 3 wherein the polyester is pigmented.
Claim 6
Dependent Claim
12 words
The process of claim 4 in which the pigment is carbon black.
Claim 7
Dependent Claim
13 words
The process of claim 4 in which the pigment is magnetic iron oxide.
Claim 8
Dependent Claim
20 words
The process of clim 3 wherein the polyester has a crystalline melting point between about 50° and about 110° C.
Claim 9
Dependent Claim
20 words
The process of clim 3 wherein the polyester has a crystalline melting point between about 50° and about 110° C.
Claim 10
Dependent Claim
30 words
The process of claim 7 wherein the copolymer is a graft copolymer prepared from a 10-24 carbon alkyl methacrylate and an aliphatic polyester which has been reacted with glycidyl methacrylate.
Claim 11
Dependent Claim
21 words
The process of claim 8 wherein both the condensation-type polymer and the aliphatic polyester of the graft copolymer are poly(butylene adipate).
Claim 12
Dependent Claim
13 words
The process of claim 9 in which the crystalline condensation-type polymer is pigmented.
Claim 13
Dependent Claim
13 words
The process of claim 10 in which the pigment is magnetic iron oxide.
Claim 14
Dependent Claim
22 words
The process of claim 8 wherein the both the condensation-type polymer and the aliphatic polyester of the graft copolymer are poly(hexamethylene sebacate).
Claim 15
Dependent Claim
22 words
The process of claim 7 wherein the copolymer is a graft copolymer prepared from an aliphatic polyester and maleic modified amorphous polypropylene.
Claim 16
Dependent Claim
21 words
The process of claim 13 wherein both the condensation-type polymer and the aliphatic polyester of the graft copolymer are poly(butylene adipate).
Claim 17
Dependent Claim
21 words
The process of claim 3 wherein both the condensation-type polymer and the aliphatic polyester of the graft copolymer are poly(hexamethylene sebacate).
References Cited (Backward Citations)
US3586654A
Cited
US3674736A
Cited
US3669922A
Cited
US3925295A
Cited
US3910846A
Cited
US4110529A
Cited
US4060511A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-05-11 | 1984-11-10 | 1985-05-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-05-11 | 1988-11-10 | 1989-05-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-05-11 | 1992-11-10 | 1993-05-12 | $7700.00 | Window Closed / Lapsed |