WO2023086857A1

WO2023086857A1 - Polyphenylene sulfide blends for three-dimensional printer filament

Info

Publication number: WO2023086857A1
Application number: PCT/US2022/079596
Authority: WO
Inventors: Charles Brandon SWEENEY; Ryan VANO; Thomas Colin MULHOLLAND; Nirup Nagabandi
Original assignee: Essentium Ipco, Llc
Priority date: 2021-11-12
Filing date: 2022-11-10
Publication date: 2023-05-19

Abstract

A polyphenylene sulfide blend and filaments formed therefrom as well as method of formulating a filament of a polyphenylene sulfide blend and a method of printing a filament of a polyphenylene sulfide blend. The polyphenylene sulfide blend includes a polyphenylene sulfide polymer, a plurality of fibers dispersed in the polyphenylene sulfide polymer, and a polyetherimide-siloxane polymer blended with the polyphenylene sulfide polymer.

Description

POLYPHENYLENE SULFIDE BLENDS FOR THREE-DIMENSIONAL PRINTER FILAMENT

FIELD

[0001] The present disclosure is directed to polyphenylene sulfide blends for three- dimensional printer filament.

BACKGROUND

[0002] Three-dimensional printing, and particularly fused filament fabrication, generally involves the deposition of filament, in the form of traces, on a printing surface to form a three- dimensional object. The traces are subsequently layered on top of each other in the z-direction in a softened or melted state. In various processes, the filament is formed of a polymer material. Polymer materials used for three-dimensional printer filaments include thermoplastic polymers, thermoplastic-elastomers, and thermoset materials. Further, the polymer materials forming the filament may include one or more additives. Such additives include fillers, such as fibers or particles.

[0003] In fused filament fabrication, the filament is deposited as traces on a print surface by an extruder. Heat and force may be applied to the filament in the extruder to force the filament through the extruder nozzle and deposit traces on the printing surface and on previously extruded traces. The application of heat and force may reduce the viscosity of the filament as it is being extruded. Further, in semicrystalline materials, the application of heat and force melt the polymer during extrusion, which may crystallize when the traces solidify.

[0004] Various problems may develop during filament extrusion and three-dimensional printing. For example, some materials may be too brittle to spool or to extrude into filament without snapping. Further, due to the nature of three-dimensional printing, the crystallization kinetics of the filament and thermal history induced by the three-dimensional printing process may lead to processing problems. These problems may result in the loss of production time and materials.

[0005] An example of such material includes unmodified polyphenylene sulfide, which may be relatively brittle. To improve brittleness, polyphenylene sulfide is often fiber reinforced with, e.g., glass fiber or carbon fiber. Polyphenylene sulfide exhibits a relatively low viscosity during processing and fiber reinforced polyphenylene sulfide tends to back flow and crystallize in the hot-cold transition region of the extrusion nozzle in the three-dimensional printer. The fibers fillers may jam in the extruder preventing movement of the filament through the extruder.

[0006] Accordingly, while the current filament formulations meet their intended purpose, there is room for the development of new and improved filament materials and three-dimensional printing methods for forming three-dimensionally printed objects.

SUMMARY

[0001] Aspects of the present disclosure are directed to a filament of a polyphenylene sulfide blend. The polyphenylene sulfide blend includes a polyphenylene sulfide polymer, a plurality of fibers dispersed in the polyphenylene sulfide polymer, and a polyetherimide-siloxane polymer blended with the polyphenylene sulfide polymer. In embodiments, the polyphenylene sulfide polymer present in the polyphenylene sulfide blend at a weight percent of 50 percent by weight to 98 percent by weight of the total weight of the polyphenylene sulfide blend. In further embodiments, the plurality of fibers are dispersed in the polyphenylene sulfide polymer in a range of 1 percent by weight to 40 percent by weight of the total weight of the polyphenylene sulfide blend. In yet further embodiments, the polyetherimide-siloxane polymer is present in the polyphenylene sulfide blend in a range of 1 percent by weight to 10 percent by weight of the total weight of the polyphenylene sulfide blend. And in yet further embodiments, the polyetherimidesiloxane polymer is present in a range of 3 to 8 percent by weight of the total weight of the polyphenylene sulfide blend and the plurality of fibers are present in a range of 10 to 20 percent by weight of the total weight of the polyphenylene sulfide blend.

[0002] In any of the above embodiments, the plurality of fibers include at least one of the following: milled carbon fiber based on polyacrylonitrile, chopped carbon fiber based on polyacrylonitrile, E-glass fiber, C-glass fiber, H-glass fiber, D-glass fiber, aramid fiber, aluminoborosilicate fiber, aluminosilica fiber, and alumina based fiber. In any of the above embodiments, the polyphenylene sulfide blend exhibits a heat of fusion in the range of 20 J/g to 40 J/g as measured by differential scanning calorimetry at a temperature ramp rate of 5 Kelvin per minute. In any of the above embodiments, the peak melting temperature of the polyphenylene sulfide blend deviates by less than 1 % from the peak melting temperature of the polyphenylene sulfide polymer and the plurality of fibers dispersed in the polyphenylene sulfide polymer.

[0003] In any of the above embodiments, the polyphenylene sulfide blend exhibits a diameter in the range of 1 mm to 4mm. In further embodiments, the filament exhibits a crosssection of the form of one of the following: a square, a rectangle, and a triangle. In yet further embodiments, the filament is formed into a plurality of layers and bonds between the plurality of layers exhibit a flexural strength in a range of 40 MPa to 48 MPa as measured according to ISO 178:2019 using an 80 mm x 10 mm x 4 mm specimen and tested in the build direction.

[0004] Further aspects of the present disclosure are directed to a method of formulating a filament of a polyphenylene sulfide blend. The method includes adding a polyphenylene sulfide polymer and a plurality of fibers to a mixing apparatus and adding a polyetherimide-siloxane polymer to the mixing apparatus. The polyphenylene sulfide polymer, the plurality of fibers, and the polyetherimide-siloxane polymer are combined in the mixing apparatus to form a polyphenylene sulfide blend. The method further includes shaping the polyphenylene sulfide blend into a polyphenylene sulfide filament.

[0005] In embodiments of the method, adding the polyphenylene sulfide polymer, as a first component, and the plurality of fibers, as a second component, is performed sequentially or simultaneously. In further embodiments of the above, adding the polyetherimide-siloxane polymer is added simultaneously with the polyphenylene sulfide polymer and the plurality of fibers. In alternative embodiments, adding the polyetherimide-siloxane polymer is added sequentially as a third component to the polyphenylene sulfide polymer and the plurality of fibers.

[0006] In any of the above embodiments, the method further includes pelletizing the shaped polyphenylene sulfide blend. In any of the above embodiments, shaping the polyphenylene sulfide blend is performed by extruding the polyphenylene sulfide blend.

[0007] In any of the above embodiments, the method further includes reducing a heat of fusion of the polyphenylene sulfide polymer blend an amount in a range of 8 percent to 25 % of a heat of fusion of the polyphenylene sulfide polymer including a plurality of fibers dispersed in the polyphenylene sulfide polymer upon combining the polyphenylene sulfide polymer, the plurality of fibers, and the polyetherimide-siloxane polymer in the mixing apparatus to form a polyphenylene sulfide blend.

[0008] Yet additional aspects of the present disclosure relate to a method of printing a filament of a polyphenylene sulfide blend. The method includes feeding a filament of a polyphenylene sulfide blend into a nozzle of a three-dimensional printer, wherein the polyphenylene sulfide blend includes a polyphenylene sulfide polymer, a plurality of fibers dispersed in the polyphenylene sulfide polymer, and a polyetherimide-siloxane polymer blended with the polyphenylene sulfide polymer. The method further includes extruding the filament from the nozzle, depositing the filament as a trace on a print surface, and depositing subsequent traces over previously deposited traces to form a three-dimensional object. In embodiments, feeding the filament of a polyphenylene sulfide blend into the nozzle includes drawing the filament from a spool from a filament canister.

BRIEF DESCRIPTION OF DRAWINGS

[0007] The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

[0008] FIG. 1 illustrates differential scanning calorimetry curves for a 15 percent by weight carbon fiber filled polyphenylene sulfide polymer with various loadings of polyetherimidesiloxane including neat (0 percent by weight), 2.5 percent by weight, 5 percent by weight, 10 percent by weight and 20 percent by weight of the total weight of the polyphenylene sulfide composition, wherein the abscissa refers to temperature (degrees C) and the ordinate refers to enthalpy (mW/mg);

[0009] FIG. 2 illustrates the effect of additive content on the heat of fusion in terms of weight percentage of polyetherimide-siloxane loadings in 15 percent by weight carbon fiber filled polyphenylene sulfide polymer relative to 15 weight percent carbon fiber filled polyphenylene sulfide without polyetherimide-siloxane (neat) including polyetherimide-siloxane present 2.5 percent by weight, 5 percent by weight, 10 percent by weight and 20 percent by weight of the total weight of the polyphenylene sulfide composition;

[0010] FIG. 3 illustrates the effect of polyetherimide-siloxane loadings on the flexural strength of 15 percent by weight carbon fiber filled polyphenylene sulfide polymer relative to the 15 percent by weight carbon fiber filled polyphenylene sulfide polymer including poly etherimidesiloxane present 2.5 percent by weight and 5 percent by weight of the total weight of the polyphenylene sulfide composition;

[0011 ] FIG. 4 illustrates a three-dimensionally printed box used for preparing testing strips to measure mechanical strength of the polymer and inter-layer bonding in the build direction (or z-direction);

[0012] FIG. 5 illustrates a method of forming a polyphenylene sulfide blend exhibiting the form of a filament;

[0013] FIG. 6 illustrates a method of forming a three-dimensional object by three- dimensional printing; and

[0014] FIG. 7 illustrates a three-dimensional printer.

DETAILED DESCRIPTION

[0015] The present disclosure is directed to a polyphenylene sulfide blend and to filament of a polyphenylene sulfide blend for three-dimensional printing as well as methods of forming the filament and printing with the polyphenylene sulfide blend. The polyphenylene sulfide polymer includes fibers and a polyetherimide-siloxane polymer dispersed in the polyphenylene sulfide polymer to provide a polyphenylene sulfide blend and filament suitable for use in, for example, a fused filament three-dimensional printing process, in addition to other processes. In aspects, the polyphenylene sulfide blend exhibits a heat of fusion (hf) in the range of 21 J/g to 27 J/g, including all values and ranges therein as measured by differential scanning calorimetry (DSC) at a temperature ramp rate of 5 kelvin per minute (K/min). In further aspects, the flexural strength in the layer bonds exhibited by the polyphenylene sulfide blend is in the range of 40 MPa to 48 MPa, including all values and ranges therein, as measured in the build direction according to ISO 178:2019 using 80 mm x 10 mm x 4 mm specimens.

[0016] To improve properties of unfilled polyphenylene sulfide, and particularly mechanical properties such as flexural strength and modulus, a plurality of fibers are dispersed in the polyphenylene sulfide polymer. The fibers include at least one of the following: carbon fibers, glass fibers, aramid fibers, and ceramic fibers. In aspects, the carbon fibers include milled or chopped carbon fibers based on polyacrylonitrile (PAN) or pitch precursors which have been oxidized and graphitized. In aspects, the glass fibers include E-glass, C-glass, H-glass, S-glass, or D-glass. In further aspects, ceramic fibers include at least one of the following aluminoborosilicate, aluminosilica, and alumina based fibers. The fibers exhibit a length in the range of 0.005 millimeters to 5 millimeters, including all values and ranges therein, such as in the range of 0.005 millimeters to 0.01 millimeters, 0.05 millimeters to 5 millimeters. Further, the fibers exhibit an aspect ratio (length to diameter) of greater than 10 to 1, such as in the range of 10 to 1 and up to 10,000 to 1, including all values and ranges therein.

[0017] Other additives may be included in the polyphenylene sulfide polymer such as mineral fillers having a particles size in the range of 0.001 millimeters to 0.1 millimeters such as clay, glass beads having a particle size in the range of 0.01 millimeters to 0.25 millimeters, carbon particles having a particles size in the range of 5 nanometers to 0.01 millimeters, graphite particles having a particles size in the range of 50 nanometers to 0.1 millimeters, polytetrafluoroethylene (PTFE), and combinations thereof. Colorants and pigments may also be included as other additives.

[0018] However, during three-dimensional printing, fiber reinforced polyphenylene sulfide polymer has a tendency crystallize in the hot-cold transition region of the extrusion nozzle in the three-dimensional printer. The low viscosity polyphenylene sulfide back-flows up and towards the heat-break section of the extrusion nozzle causing the filament to jam in the extruder nozzle. To reduce and prevent this tendency polyetherimide-siloxane is added to the fiber reinforced polyphenylene sulfide polymer, providing a fiber reinforced polyphenylene sulfide and polyetherimide-siloxane polymer blend, referred to herein as a polyphenylene sulfide blend.

[0019] In aspects, the polyphenylene sulfide polymer is present in the polyphenylene sulfide blend at a weight percent of 50 percent by weight to 98 percent by weight of the total weight of the polyphenylene sulfide blend, including all values and ranges therein. The fibers or fillers are incorporated into the polyphenylene sulfide polymer in a range of 1 percent by weight to 40 percent by weight of the total weight of the polyphenylene sulfide blend, including all values and ranges therein. The polyetherimide-siloxane is present in a range of 1 percent by weight to 10 percent by weight of the total weight of the polyphenylene sulfide blend, including all values and ranges therein. Other additives, including those described above as well as one or more of processing aids, flow modifiers, thermal stabilizers, UV stabilizers, and others, are optionally present, wherein the total percentage of the other additives is in a range of 0.1 percent by weight to 20 percent by weight of the total polyphenylene sulfide blend, including all values and ranges therein. The total weight percentage of the polyphenylene sulfide blend, including the various components noted above, is 100 percent by weight.

[0020] In further aspects, the polyphenylene sulfide blends include polyetherimide- siloxane in the range of 3 percent to 8 percent by weight of the total weight of the polyphenylene sulfide blend and a plurality of fibers in the range of 10 percent to 20 percent by weight of the total weight of the polyphenylene sulfide blend. In yet further aspects, the polyphenylene sulfide blends include polyetherimide-siloxane in the range of 4 percent to 6 percent by weight of the total weight of the polyphenylene sulfide blend and fibers in the range of 14 percent to 16 percent by weight of the total weight of the polyphenylene sulfide blend. In a yet further aspect, a polyphenylene blend includes polyetherimide-siloxane present at 5 percent by weight of the total polyphenylene sulfide blend and carbon fiber present at 15 percent by weight of the total polyphenylene sulfide blend.

[0021 ] In aspects, the polyphenylene sulfide blend exhibits a reduction in the heat of fusion (hf) of at least 3 percent of the heat of fusion of the fiber reinforced polyphenylene sulfide polymer, including a reduction in the range of 3 percent to 30 percent of the heat of fusion of the fiber reinforced polyphenylene sulfide polymer. In further aspects, the polyphenylene sulfide blend exhibits a heat of fusion (hf) in the range of 20 J/g to 40 J/g, including all values and ranges therein such as 21 J/g to 27 J/g, including all values and ranges therein as measured by differential scanning calorimetry (DSC) at temperature ramp rate of 5 kelvin per minute (K/min). FIG. 1 illustrates DSC measurements, obtained using a temperature ramp rate of 5 kelvin per minute (K/min), for a 15 percent by weight carbon fiber reinforced polyphenylene sulfide with 2.5, 5, 10, and 20 percent by weight polyetherimide-siloxane additions (the weight percent being the total weight of the polyphenylene sulfur composition). While a decrease in heat of fusion was exhibited of 8 % to 25 % reduction in the heat of fusion (hf) as compared to the fiber reinforced polyphenylene sulfide polymer, the peak melting temperature remained consistent, deviating by less than 1 % from that of the fiber reinforced polyphenylene sulfide polymer. FIG. 2 provides a graph illustrating the effect of the addition of the polyetherimide-siloxane at loadings of 2.5, 5, 10 and 20 percent by weight on the 15 percent by weight fiber reinforced polyphenylene sulfide polymer. [0022] In further aspects, as illustrated in FIG. 3, the flexural strength in the layer bonds (i.e., in the build direction) exhibited by the polyphenylene sulfide blend is in the range of 40 MPa to 48 MPa, including all values and ranges therein, as measured in the build direction according to ISO 178:2019 using 80 mm x 10 mm x 4 mm specimens cut from the sides of a three-dimensionally printed box, such as the box illustrated in FIG. 4. The square, hollow three-dimensionally printed box 10 has 4 mm thick side walls 12. From the box 10, specimens 14 are cut using a CNC router. To print the box, a trace 16 is deposited in a plane defined by a first axis Al and a second axis A2 to form the bottom 18 of the box. Additional traces 16n are subsequently deposited on top of each other in a third axis A3, commonly referenced as a z-axis or build direction to form the sidewalls 12 of the box.

[0023] Aspects of the present disclosure are directed to the polyphenylene sulfide blend exhibiting the form of a filament and methods of forming a filament of the polyphenylene sulfide blend. Reference is made to FIG. 5 illustrating a method 20 of providing a filament of a polyphenylene sulfide blend. In aspects, the method 20 includes at blocks 22 and 24 blending the polyphenylene sulfide polymer, the fibers, the polyetherimide-siloxane, and other optional additives, referenced above in a mixing apparatus. A mixing apparatus includes, for example, a blender or an extruder, such as a single screw or twin screw extruder. In aspects, the polyphenylene sulfide polymer and the fibers are provided as a reinforced polyphenylene sulfide polymer and added at once at block 22. In alternative aspects, the polyphenylene sulfide polymer and the fibers are provided as separate components and are added to the mixing apparatus at the same time (simultaneously) or sequentially, wherein the fibers are added to the polymer at block 22. The fibers are dispersed through the polyphenylene sulfide polymer. Further, at block 24, the polyetherimide-siloxane is added at the same time (simultaneously) as the polyphenylene sulfide polymer and the fibers or added to the polyphenylene sulfide polymer and the fibers separately. At block 26, the polyetherimide-siloxane is dispersed through the polyphenylene sulfide polymer. In aspects, the components of the polyphenylene sulfide blend are mixed in a twin screw extruder in blocks 22 through 26 and optionally pelletized at block 28 and then extruded into a filament at block 30. In other aspects, the components of the polyphenylene sulfide blend are mixed in a dry blender and fed into an extruder at blocks 22 through 26 and extruded directly into the form of a filament at block 30. In further aspects, the components of the polyphenylene sulfide blend are introduced directly into the extruder, through one or more ports, at blocks 22 and 24, and extruded directly into the form of a filament at block 30. In aspects, the filament exhibits a diameter in the range of 1 mm to 4 mm, including all values and ranges therein, such as 1.75 mm and 2.85 mm. In aspects, the filament cross-section exhibits the shape of a circle or ellipse. In other aspects, the filament cross-section exhibits the general form of a square, rectangle, triangle or other shapes.

[0024] Aspects of the present disclosure are also directed to methods of printing a polyphenylene sulfide blend. Reference is made to FIGS. 4, 6 and 7. A three-dimensional printer 100, illustrated in FIG. 7, is provided. The printer includes a support bed 106 having a printing surface 108. A number of filament canisters 122 are provided including spooled filament 124 of the above referenced polyphenylene sulfide composition. The filament buffer 126 draws the filament 124 from the filament canisters 122 and spools seated within the canisters (not illustrated) and the filament 124 is fed into the print head 128, including the heated extruder nozzle 130 therein. The print head 128 is mounted on an X-Y gantry 132, which moves the print head 128 in a plane defined by a first axis Al and a second axis A2, commonly referred to as the X-Y plane. The support bed 106 moves up and down relative to the print head 128 in the build direction along axis A3, commonly referred to as the Z-axis, by a Z-axis gantry 120. In additional or alternative aspects, X-Y gantry 132 moves in the build direction A3. The printer includes a controller 152 that controls the various functions in the three-dimensional printer 100 including the movement of the print head 128 via the X-Y gantry 132, the heating of the extruder nozzle 130 in the print head 128, the movement of the support bed 106 in the build direction on the Z-axis gantry 120, the heating of the process chamber 104 defined by the printer frame 102, the feeding of the filament 124 through the filament buffer 126, etc. One or more user interfaces 156, 158 are provided to allow an operator to adjust the functions of the three-dimensional printer 100. In the illustrated example a screen 156, including a graphic user interface is provided, and an input in the form of a keyboard 158 is provided.

[0025] The controller 152 includes one or more processors 160 for performing the method of forming a three-dimensional object. The processor 160, in aspects, include microprocessors and, in further aspects are configured for distributive processing of the various data inputs and outputs for the three-dimensional printer. The processor 160 includes executable code to perform a method 40 of printing the polyphenylene sulfone blend filament. The method 40 includes feeding a filament 124 of a polyphenylene sulfide blend into the nozzle of a three-dimensional printer 100 at block 42. The filament 124 is drawn from the filament canister 122, travels through the filament buffer 126. The filament 124 is forced through the extruder nozzle 130 at block 44 where it is heated and a force is applied to the filament 124 to soften and, in aspects, melt the filament 124 at block 46. The filament 124 is then deposited as a trace 16 (FIG. 4), 130 (FIG. 7) of filament 124 on the print surface 108 at block 48. Subsequent traces 16n are then deposited on top of previously deposited traces 16, 16n in the build direction (or z-direction) at block 50 to form a three dimensional object such as the hollow, square box 10 illustrated in FIG. 4. It should be appreciated that any number of three-dimensional objects may be printed assuming a variety of geometries. [0026] The modified polyphenylene sulfide compositions and filaments discussed herein offer several advantages. These advantages include, for example, an improvement in mechanical properties, including an increase in the stiffness and toughness of the filaments formed from the compositions. The improvement in the mechanical properties provide an improvement in the ability to spool the filament and feed the filament into the printer without snapping. These advantages further include an improvement in process stability during the printing process. The modification of a polyphenylene sulfide including an additive, and particularly fiber additives, such as carbon fiber or glass fiber, with polyetherimide-siloxane polymers improves the reliability of the printing process by eliminating nozzle jams. Further, due to the decrease in the heat of fusion, the modification of a polyphenylene sulfide including an additive, and particularly fiber additives, such as carbon fiber or glass fiber, with polyetherimide-siloxane polymers improves bonding between adjacent traces during the three-dimensional printing process.

[0027] The description of the present disclosure is merely exemplary in nature and variations that do not depart from the gist of the present disclosure are intended to be within the scope of the present disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the present disclosure.

Claims

What is claimed is:

1. A filament of a polyphenylene sulfide blend, comprising: a polyphenylene sulfide polymer; a plurality of fibers dispersed in the polyphenylene sulfide polymer; and a polyetherimide-siloxane polymer blended with the polyphenylene sulfide polymer.

2. The filament of a polyphenylene sulfide blend of claim 1, wherein the polyphenylene sulfide polymer present in the polyphenylene sulfide blend at a weight percent of 50 percent by weight to 98 percent by weight of a total weight of the polyphenylene sulfide blend.

3. The filament of a polyphenylene sulfide blend of claim 1, wherein the plurality of fibers are present in a range of 1 percent by weight to 40 percent by weight of a total weight of the polyphenylene sulfide blend.

4. The filament of a polyphenylene sulfide blend of claim 1, wherein the polyetherimide- siloxane polymer is present in the polyphenylene sulfide blend in a range of 1 percent by weight to 10 percent by weight of a total weight of the polyphenylene sulfide blend.

5. The filament of a polyphenylene sulfide blend of claim 1, wherein the polyetherimide- siloxane polymer is present in a range of 3 to 8 percent by weight of a total weight of the polyphenylene sulfide blend and the plurality of fibers are present in a range of 10 to 20 percent by weight of a total weight of the polyphenylene sulfide blend. The filament of a polyphenylene sulfide blend of claim 1, wherein the plurality of fibers include at least one of the following: milled carbon fiber based on polyacrylonitrile, chopped carbon fiber based on polyacrylonitrile, E-glass fiber, C-glass fiber, H-glass fiber, D-glass fiber, aramid fiber, aluminoborosilicate fiber, aluminosilica fiber, and alumina based fiber. The filament of a polyphenylene sulfide blend of claim 1, wherein the polyphenylene sulfide blend exhibits a heat of fusion in a range of 20 J/g to 40 J/g as measured by differential scanning calorimetry at a temperature ramp rate of 5 Kelvin per minute. The filament of a polyphenylene sulfide blend of claim 1, wherein a peak melting temperature of the polyphenylene sulfide blend deviates by less than 1 % from a peak melting temperature of the polyphenylene sulfide polymer and the plurality of fibers dispersed in the polyphenylene sulfide polymer. The filament of a polyphenylene sulfide blend of claim 1, wherein the polyphenylene sulfide blend exhibits a diameter in the range of 1 mm to 4mm. The filament of a polyphenylene sulfide blend of claim 9, wherein the filament exhibits a cross-section of the form of one of the following: a square, a rectangle, and a triangle. The filament of a polyphenylene sulfide blend of claim 9, wherein the filament is formed into a plurality of layers and bonds between the plurality of layers exhibit a flexural strength in a range of 40 MPa to 48 MPa as measured according to ISO 178:2019 using an 80 mm x 10 mm x 4 mm specimen and tested in a build direction. A method of formulating a filament of a polyphenylene sulfide blend, comprising: adding a polyphenylene sulfide polymer and a plurality of fibers to a mixing apparatus; adding a polyetherimide-siloxane polymer to the mixing apparatus; combining the polyphenylene sulfide polymer, the plurality of fibers, and the polyetherimide-siloxane polymer in the mixing apparatus to form a polyphenylene sulfide blend; and shaping the polyphenylene sulfide blend into a filament. The method of claim 12, wherein adding the polyphenylene sulfide polymer, as a first component, and the plurality of fibers, as a second component, is performed sequentially or simultaneously. The method of claim 12, wherein adding the polyetherimide-siloxane polymer is added simultaneously with the polyphenylene sulfide polymer and the plurality of fibers. The method of claim 14, wherein adding the polyetherimide-siloxane polymer is added sequentially as a third component to the polyphenylene sulfide polymer and the plurality of fibers.

16 The method of claim 12, further comprising pelletizing the shaped polyphenylene sulfide blend. The method of claim 12, wherein shaping the polyphenylene sulfide blend is performed by extruding the polyphenylene sulfide blend. The method of claim 12, further comprising reducing a heat of fusion of the polyphenylene sulfide polymer blend an amount in a range of 8 percent to 25 % of a heat of fusion of the polyphenylene sulfide polymer including a plurality of fibers dispersed in the polyphenylene sulfide polymer upon combining the polyphenylene sulfide polymer, the plurality of fibers, and the polyetherimide-siloxane polymer in the mixing apparatus to form a polyphenylene sulfide blend. A method of printing a filament of a polyphenylene sulfide blend, comprising: feeding a filament of a polyphenylene sulfide blend into a nozzle of a three-dimensional printer, wherein the polyphenylene sulfide blend includes a polyphenylene sulfide polymer, a plurality of fibers dispersed in the polyphenylene sulfide polymer, and a polyetherimide-siloxane polymer blended with the polyphenylene sulfide polymer; extruding the filament from the nozzle; depositing the filament as a trace on a print surface; and depositing subsequent traces over previously deposited traces to form a three- dimensional object.

17

20. The method of claim 19, wherein feeding the filament of a polyphenylene sulfide blend into the nozzle includes drawing the filament from a spool from a filament canister.

18