Polyester resin and industrial yarn process
AssigneeHoneywell International Inc.
InventorsThomas Y-T. Tam, Samir Z. Abdalla, James G. Neal, John A. Young, Hong-Jian J. Sha, Hu Zhixuan
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Abstract
A polyester resin, a method for its preparation, the polyester prepared by the method, a method for manufacturing therefrom at increased productivity a dimensionally stable polyester yarn having a low fray count, and the yarn thereby produced. The polyester resin is prepared from high purity terephthalic acid having a particle size distribution described by a Weibull function with narrow ranges of characteristic size and shape factor. The polyester resin has a low filter-blinding index. The polyester yarn is useful for tires, industrial products and other applications.
Claims19
A fiber grade polyester resin having an intrinsic viscosity of at least about 0.8 dl/g measured in a 60/40 (w/w) mixture of phenol/tetrachloroethane at 25° C. and having a filter-blinding index less than about 10,000 Pa-cm2/g measured at a throughput of 1.25 g/min of melt flow per cm2 of filter area for 244 minutes at 300° C. through a 128×905 mesh/cm twilled Dutch weave screen having apertures less than 8 microns in dimension.
A method of preparing a fiber grade polyester resin comprising the steps of:
- (a) selecting a high purity terephthalic acid having a particle size distribution described by a Weibull function with an index of determination of 0.990 or greater, said distribution having a characteristic size from about 100 to about 140 micrometers and a shape factor from about 1.5 to about 2.1;
- (b) reacting the terephthalic acid with a glycol and polymerizing to form a linear polyester having an intrinsic viscosity of at least about 0.8 dl/g measured in a 60/40 (w/w) mixture of phenol/tetrachloroethane at 25° C.
A method of preparing a dimensionally stable polyester yarn at increased productivity and reduced fray count comprising the steps:
- a) selecting a high purity terephthalic acid having a particle size distribution described by a Weibull function with an index of determination of about 0.990 or greater, said distribution having a characteristic size from about 100 to about 140 micrometers and a shape factor from about 1.5 to about 2.1;
- b) reacting the terephthalic acid with a glycol and polymerizing to form a linear polyester having an intrinsic viscosity of at least about 0.8 dl/g measured in a 60/40 (w/w) mixture of phenol/tetrachloroethane at 25° C.;
- c) extruding the polyester through a shaped extrusion orifice having a plurality of openings to form a molten spun yarn;
- d) withdrawing and solidifying the molten spun yarn at sufficient speed to form a crystalline, partially oriented yarn;
- and
- e) hot drawing the yarn to a total draw ratio of about 1.5:1 to about 3:1.
A fiber grade polyester resin having an intrinsic viscosity of at least about 0.8 dl/g measured in a 60/40 (w/w) mixture of phenol/tetrachloroethane at 25° C. and having a filter-blinding index less than about 10,000 Pa-cm2/g measured at a throughput of 1.25 g/min of melt flow per cm2 of filter area for 244 minutes at 300° C. through a 128×905 mesh/cm twilled Dutch weave screen having apertures less than 8 microns in dimension prepared by the process comprising the steps of:
- (a) selecting a high purity terephthalic acid having a particle size distribution described by a Weibull function with an index of determination of 0.990 or greater, said distribution having a characteristic size from about 100 to about 140 micrometers and a shape factor from about 1.5 to about 2.1;
- and
- (b) reacting the terephthalic acid with a glycol and polymerizing to form a linear polyester having an intrinsic viscosity of at least about 0.8 dl/g.
A dimensionally stable polyester yarn prepared by the process comprising the steps of:
- (a) selecting a high purity terephthalic acid having a particle size distribution described by a Weibull function with an index of determination of about 0.990 or greater, said distribution having a characteristic size from about 100 to about 140 micrometers and a shape factor from about 1.5 to about 2.1;
- (b) reacting the terephthalic acid with a glycol and polymerizing to form a linear polyester having an intrinsic viscosity of at least about 0.8 dl/g measured in a 60/40 (w/w) mixture of phenol/tetrachloroethane at 25° C.;
- (c) extruding the polyester through a shaped extrusion orifice having a plurality of openings to form a molten spun yarn;
- (d) withdrawing and solidifying the molten spun yarn at sufficient speed to form a crystalline, partially oriented yarn;
- and
- (e) hot drawing the yarn to a total draw ratio of about 1.5:1 to about 3:1.
Dependencies are inferred from the claim text.