JP2007532334A - Abrasive article, composition, and method for producing the same - Google Patents

Abstract

  A composition comprising superabrasive grains, a thermoplastic polymer having a processing temperature of at least 280 ° C., and a filler, and a method for producing the same. The composition is useful for making abrasive articles.

Description

  The present invention relates to abrasive articles and methods and compositions for making abrasive articles. In particular, the present invention relates to a bonded abrasive tool that includes superabrasive grit.

The term “superabrasive” generally refers to an abrasive material having exceptional hardness. Typical “conventional” abrasives such as aluminum oxide and silicon carbide have a hardness in the range of 2000-2500 kg / mm ² , and “super polished” cubic boron nitride (cBN) and diamond are 4500 each. And a hardness on the order of 8000 kg / mm ² .

  There are a variety of bonded abrasive articles including superabrasive grit such as diamond and cubic boron nitride. Examples of such abrasive articles include abrasive wheels, scouring bars, saw blades, cutting sticks, mounted points, snuggling wheels, dressing tools, cup wheels, center dent grinding wheels, grinding wheels, and flap wheels. and so on.

  Grinding wheels typically include a hub and an operating rim secured to the outer surface of the hub. The hub may be manufactured from metal, resin plastic, or a combination thereof and generally includes a means for facilitating attachment to a grinding machine. The working rim may be a single annular piece or may be formed from multiple segments. The working rim typically includes superabrasive grains dispersed in a metal matrix, a glass matrix, or a thermosetting resin such as phenol-formaldehyde, urea-formaldehyde or melamine-formaldehyde resin. Thermosets are used because of their ability to withstand the high temperatures associated with grinding wheel operation and because of the brittle nature of many thermoset resins allow them to degrade during grinding Has been.

  The manufacture of bonded abrasive products, such as grinding wheels, using thermosetting resins is generally long and slow. Articles are typically produced by compression molding or by constant volume molding in which the mold is filled with the correct volume of granular abrasive filler and binder. The binder may be in powder form, liquid, or a combination thereof. Heating is conducted by conduction, and heating relies on sufficient surface contact between the mold and the heating pressure platen, so the mold volume is filled exactly so that the top and bottom are flush with the mold wall. It is necessary to be done. Molding materials typically have insufficient thermal conductivity, and it may be necessary to heat the powder mixture for several hours to ensure sufficient cure throughout the abrasive article. Also, the molding process produces emissions that are not only unpleasant but also cause undesirable environmental effects.

  It has been proposed to produce resin bonded abrasive products using an injection molding method.

  For example, Patent Document 1 discloses an abrasive article including a molded abrasive body made from an injection-molded polymer material having an abrasive material and a secondary filler material that is homogeneously dispersed over the abrasive material. The body has a heat selected from a thermoplastic polymer material having a diamond hardness abrasive grit of 1 volume percent to 20 volume percent, a secondary filler of 5 volume percent to 80 volume percent, and a softening point temperature greater than 100 ° C. and less than 250 ° C. 5% to 90% by volume of the moldable polymer, and a thermosetting polymer. The thermal properties of resin bonded abrasive products containing such thermoplastic polymer materials are not good for all applications.

It has also been proposed to produce a specific resin bonded abrasive product using a thermoplastic polymer having a higher softening point temperature as the binder resin. Patent Document 2 discloses a method for manufacturing an injection-molded saw segment,
(A) A mass of superhard abrasive grains dispersed in a non-porous thermoplastic polymer matrix in a barrel of an injection molding machine is heated at a temperature of about 280 ° C. to 400 ° C. so that the abrasive content of the segment is at least 4 volumes. The process, which is a percentage
(B) injecting the heated product of step (a) into a mold at a pressure of about 70 MPa to 150 MPa;
(C) maintaining the injected product of step (b) in the mold at a pressure of about 35 MPa to about 75 MPa for at least about 2 to about 10 seconds.
EP0555114 specification US Pat. No. 5,314,512

According to one aspect of the invention,
Superabrasive grains,
A thermoplastic polymer having a processing temperature of at least 280 ° C .;
And a composition comprising a filler,
The thermoplastic polymer is present in an amount sufficient to bind the composition, and the filler comprises spherical particles present in an amount of at least 40 volume percent of the composition.

  According to a second aspect of the present invention, there is provided a bonded abrasive product comprising a plurality of abrasive grains bonded together by a bonding medium to a shaped mass formed from a composition as described above.

According to yet another aspect of the invention,
Heating the above composition at a temperature in the range of 280 ° C. to 400 ° C. to provide a heated composition;
Injecting the heated composition into a mold;
Cooling the heated composition to provide a bonded abrasive article. A method of manufacturing a bonded abrasive article is provided.

  The mold can be advantageously heated at a temperature of at least 150 ° C. to 250 ° C. prior to injection. The injection pressure is generally at least in the range from 70 MPa to 210 MPa.

As used in the context of the present invention, the term “superabrasive grit” refers to an abrasive grit having a hardness greater than 4000 kg / mm ² .

  In accordance with the present invention, the composition can be injection molded without great difficulty, and the resulting abrasive product typically exhibits good performance in terms of material removal. Therefore, a composition comprising superabrasive grains and a thermoplastic polymer having a relatively high crystallization melting point can be improved by adding a relatively large amount of spherical particles as a filler.

  Spherical fillers having an average particle size ranging from at least 10 micrometers to 2000 micrometers may be used at high filler levels ranging from at least 40 volume percent to 70 volume percent or more of the composition. It can be seen that a composition having a suitable viscosity for injection molding is provided. Many conventional fillers have irregularly shaped particles or acicular particles. During injection molding, the filler particles are required to flow relative to each other, and the interparticle friction between irregularly shaped particles is high, resisting flow and thereby increasing the viscosity of the composition. In contrast, spherical particles flow easily relative to each other, the viscosity increase provided by interparticle friction is significantly reduced, and higher compounding levels of filler can be successfully used for injection molding.

  Spherical filler particles suitable for use in the present invention include glass spheres, ceramic spheres and mixtures thereof. Preferred filler particles include soda lime borosilicate glass spheres, calcium carbonate spheres and silica-alumina ceramic spheres. The filler particles generally have an average particle size in the range of at least 10 micrometers to 2000 micrometers, more preferably at least 10 micrometers to 400 micrometers. Particularly useful are particles having an average particle size in the range of at least 25 micrometers to 50 micrometers.

  The spherical particles are at least 40, 45, or 50 volume percent to 60, 65, or 70 volume percent or more of the composition, such as at least 45 volume percent to 65 volume percent, preferably at least 50 volume percent to 60 volume percent of the composition. Present in amounts ranging up to volume percent.

  If additional fillers do not adversely affect the melt viscosity of the composition and interfere with injection molding, the composition may contain small amounts of other fillers such as silicon carbide, aluminum oxide, copper powder, aluminum powder, silica Further, glass fiber or the like may be contained.

  The selection of the thermoplastic polymer generally depends on the temperature that can be produced in the end use of the abrasive article. The thermoplastic polymer has a processing temperature of at least 280 ° C, generally 280-420 ° C, preferably 280-400 ° C. The processing temperature is the temperature at which the polymer flows under pressure that makes it suitable for injection molding. Processing temperatures for thermoplastic polymers are extensively cited in the literature.

  Thermoplastic polymers are typically polyetheretherketone (PEEK), polyetherketone (PEK), polyaryletherketone, polyaryletheretherketone, poly (amide-imide) (PAI), polyphenylene sulfide (PPS), Selected from engineering thermoplastics such as polyarylene sulfide (PAS), polyethersulfone (PES), polyetherimide (PEI) and liquid crystal polymer (LCP). Such materials are readily commercially available. For example, PEEK is commercially available from Victrex plc, UK, under the trade name “VICTREX”, and PPS is from Fortron Industries, USA. It is marketed under the trade name “FORTRON”.

  Two or more polymers may be used simultaneously in the polymer matrix to use the beneficial properties of each polymer. For example, a liquid crystal polymer (LCP) may be used with polyetheretherketone (PEEK) to promote the free-flow properties of PEEK, which has a low melt viscosity of LCP and a relatively high viscosity.

  The thermoplastic polymer is present in an amount sufficient to bind the composition, which is generally from at least 20, 30, or 35 volume percent to 45, 50, or 59 volume percent, or more of the composition, such as An amount of at least 30 volume percent to 50 volume percent, preferably at least 35 volume percent to 45 volume percent of the composition.

  The superabrasive grit used in the present invention is generally selected from diamond, cubic boron nitride and mixtures thereof. The superabrasive grit has an average particle size in the range of at least 30 micrometers to 300 micrometers, or more, generally at least 50 micrometers to 150 micrometers, preferably at least 90 micrometers to 105 micrometers. The superabrasive grit generally comprises at least 2.5 volume percent to 20 volume percent of the composition, preferably about 5 volume percent of the composition.

  Examples of diamonds that can be used are all resin-bonded brands 200/230 sold under the trade name “EDA2021” from Edel Industrial Diamond (EID), London, UK. Resin-bonded brands 140/170 marketed under the names “SYN GREEN” and “SYN BLACK”, and metal-bonded brands 140/170 marketed under the trade name “EDA2050” Various diamond brand sizes: 200/230 = 63-75 micrometers, 140/170 = 90-105 micrometers, LGD10 120/140 (105-125 micrometers) and LGD10 10 / 120 (125-150 micrometers) in the USA, California, San Jose Longer Corporation are commercially available (Longer Inc., San Jose, California, USA) from.

  Diamond aggregate particles having an aggregate particle size greater than 360 micrometers may be used.

  “Metal-bonded” and “resin-bonded” diamonds are two names known in the superabrasive industry, and they refer to commonly used formulation types, ie “metal-bonded” diamonds generally consist mostly of metals. Used in superabrasive products, “resin bonded” diamond is generally used in superabrasive products consisting mostly of organic resins. “Metal-bonded” diamonds differ from “resin-bonded” diamonds in that metal-bonded diamonds are typically more massive in appearance and stronger. This toughness is required because metal bonded applications are much more demanding than resin bonded applications, and metal bonded diamond must be able to withstand the rigors of the environment. On the other hand, resin-bonded diamonds are typically much more fragile and less bulky-they are designed to break down and "sharp themselves" as new diamonds are continuously exposed at the cutting interface. “Blockiness” refers to the morphology of diamond particles and serves as an indicator of diamond performance. The lump diamond morphology tends to be a cubic octahedron geometry, providing a very tough, hard-wearing diamond, but less lumpy diamonds are more acicular and form `` self- There is a tendency to break down by a "sharpening" mechanism.

  It has been found that the presence of a coupling agent, especially in particulate form, can improve the molding properties of the composition by reducing the melt viscosity. Coupling agents may be mixed with charge-providing fillers and / or abrasive grains, which tend to reduce contact between particles, thereby reducing frictional resistance between particles during injection molding. Suitable coupling agents include organosilanes, zircoaluminates, zirconates, and titanates. The coupling agent is generally present in an amount of at least 0.1 to 2 weight percent of the filler. The coupling agent may be applied directly into the mixture of binding medium, abrasive grit and filler. Alternatively, the abrasive grit and / or filler may be pretreated with a coupling agent.

  The injection molding method may use conventional equipment. A suitable injection molded structure or cavity is produced according to the desired form of the abrasive article. The ingredients of the polishing composition are mixed and heated at a temperature that provides a suitable viscosity for injection molding. The temperature generally depends on the melt viscosity of the thermoplastic material, the degree of filler, the presence of a coupling agent, and the like. In general, the temperature is in the range of at least 280 ° C to 400 ° C. The heated composition is injected into the mold under an injection pressure typically in the range of at least 70 MPa to 210 MPa. The mold may be preheated (eg, at a temperature in the range of at least 150 ° C. to 250 ° C.) to facilitate injection of the composition. Thereafter, the mold is cooled to solidify the polishing composition, and the molded article is taken out.

  The shaped abrasive article may be in any desired form. A preferred form is a grinding wheel. The grinding wheel typically may range in diameter from at least about 0.1 cm to about 2 meters, more typically from at least 1 cm to about 2 meters. Typically, the grinding wheel thickness may range from at least about 0.001 cm to about 1 meter, more typically from at least about 0.01 cm to about 0.5 meter. However, abrasive articles include abrasive wheels, polishing bars, saw blades, cutting sticks, mounted points, snuggling wheels, dressing tools, cup wheels, polishing wheels, cut-off wheels, center dent grinding wheels, flap wheels, etc. Other forms may be taken.

  The present invention is illustrated by the following examples which disclose the production of a diamond deburring wheel suitable for deburring or raising ceramic or glass type materials. Such materials include ceramic tiles, glass, and other materials that are hard and brittle. The deburring wheel consisted of a working rim made by injection molding the polishing composition. The working rim had an outer diameter of 150 mm, an inner diameter of 90 mm and a thickness of 8 mm.

Test Method The performance of a deburring wheel for deburring tiles is A. (Thibaut SA, rue de Caen, 14500 Ville, France). This was evaluated using a Tybaut machine, T110S, which is a rotary grinding / polishing machine available from Ville, France.

  Tile is key operation p. “KEOPE GRANITI” 30 cm × 30 cm manufactured by a (Keope Spa, Via Statale 467, 21-42013, Casal Grande (RE), Italy, (Casal grande (RE) Italy) It was a porcelain product.

The test procedure is as follows.
1. Record the mass of the new dry tile.
2. Record the mass of the unused deburring wheel.
3. Place the tiles in place on the Tibor machine and fix them.
4). Place the deburring wheel in place on the tibo machine.
5). Activate the tibo machine to allow water to flow into the tibo head.
6). When all equipment is immersed in the cooling water, the rotating deburring wheel is brought into contact with the tile edge surface.
7). Tibaud's head is manually moved back and forth at a controlled speed along the tile edge at a pressure of 80 psi (0.6 MPa) for a total of 60 seconds.
8). Remove the deburring wheel from the tile edge and switch off the Tibor machine.
9. Remove the tiles from the tibo machine bed.
10. Dry the tile with absorbent paper, blow dry with compressed air and place the tile in a heated oven at 105 ° C. for 5 minutes to ensure that all traces of water are removed.
11. The tile is removed from the furnace, weighed, and the mass loss is recorded.
12 Place the tiles again on the tibo bed and repeat the test on the remaining 3 sides of the tiles (steps 4-11).
13. After all four sides of the tile were deburred, the deburring wheel was removed from the tibo machine, the wheel was dried with absorbent paper, blown dry with compressed air, and the tile was heated at 105 ° C. for 30 minutes. Place in furnace and ensure all traces of water are removed.
14 Record the mass loss of the drying wheel.
15. Repeat steps 1-14 for a total of 5 tiles.
16. The results are expressed as “total cut” in grams of total mass loss for 5 tiles.

  Definition of “total cut amount”: The total cut amount is the cumulative total mass of tiles removed by the deburring wheel during processing of the five tiles (20 edges) with the tibo.

  Definition of “total wheel mass loss”: Total wheel mass loss is the cumulative sum of wheel mass lost after deburring 20 tile edges (5 tiles total).

  Definition of “diamond efficiency index”: The diamond efficiency index is calculated as follows. The diamond efficiency index is equal to α multiplied by the mass loss of the tile divided by the mass loss of the wheel, where α = the proportion of the mass of diamond present in the initial formulation.

  Since the density and ratio of the other components are known and the volume ratio of diamond is known for each formulation, the total lost wheel mass is measured so that the mass of diamond loss can be quantified. The diamond efficiency index is then calculated by dividing the mass of tile lost in the test by the mass of diamond lost in the test. During injection molding, it was assumed that there was a homogeneous distribution of diamond throughout the structure.

Materials The following materials were used in the examples.
Glass Bubble-Available as 3M Scotchlite Glass Bubble S60 / 10000 from 3M Company, St. Paul, Minnesota, USA, 3M Company, St. Paul, Minnesota, USA. The average diameter of the glass bubbles is 30 micrometers, 80% by volume is 15 to 55 micrometers, and the maximum diameter is 65 micrometers.

  Available under the trade name "3M ZEROSPHERE TMG-850" from Microsphere-3M Company. The average diameter of the microspheres is 40 micrometers, 80% by volume is 12-100 micrometers, and the maximum diameter is 200 micrometers.

  Microbeads—solid glass spheres available under the trade designation “MB300 / 400” from Microbeads AG, Brugg, Switzerland. The particle size of the glass sphere is in the range of 300 to 400 micrometers.

CaCO ₃ sphere-a calcium carbonate sphere with a particle size of 2000 micrometer upper limit, available from Lawrence Industries Ltd., Staffordshire, UK under the trade designation "SPHERICARB" .

  PEEK-Polyaryletheretherketone commercially available under the trade name "150PF" from Victrex plc, Lancasshire, UK, Lancashire, UK.

  PPS-Fortron Industries, Ticona GmBH of Frankfurt am Main, Germany, European Customer Service (commercially available from Fortron Industries, Ticona GMBH, European Customer Service, Frankfurt Am Main, Mercury Fort 9 from Germany) Polyphenylene sulfide.

  KR135SP / H—monoalkoxy titanate coupling agent marketed under the trade designation “CAPOW KR135SP / H” from Kenrich Petrochemicals, Bayonne, New Jersey, USA, Bayonne, NJ.

  KR12 / H-Titanate coupling agent commercially available from Kenrich Petrochemicals under the trade name “CAPOW KR12 / H”.

  PTS—Phenyltrimethoxy, marketed under the trade name “DYNASILAN” 9165 from Degussa AG, Aerosil & Silanes, Frankfurt, Maine, Germany, Frankfurt, Germany Silane.

  DL70-Degassa AG, a powdered vinyl silane commercially available from Aerosil & Silans under the trade name “SILAN 9116 DL70 DRY LIQUID”.

  Diamond 1—A resin-bonded brand 140/170 sold under the trade name “SYN BLACK” from Edel Industrial Diamond (EID), London, UK.

  Diamond 2—360 / 120 vitrified diamond agglomerates commercially available from the National Research Company, Chesterfield, Michigan, USA. 360/120 refers to the dimensions of 360 micrometer cubic glass encapsulating 120 micrometer diamond.

  Working rims for deburring wheels were produced by injection molding using the composition described in Table 1 (numbers are volume percent of the composition). Since the difficulty of injection molding is affected by the surface area of the filler particles, which depends on the number of particles present (as well as the particle size), the mass percent value is confusing due to density changes, so the numbers are in volume percent expressed. The volume percent indicates the formulation in a normalized “even state”. For example, in volume percent all formulations contain the same amount of diamond, however, if the result is converted to weight percent, the diamond is not represented proportionally, and the amount of diamond is actually the same for each It looks as if it varies between formulations.

Ｔ＝微量 Table 1

T = Trace amount

  The resulting wheel was tested as described above. The results are listed in Table 2.

The results of these tests are described in FIGS.
FIG. 1 shows a bar graph of mass (cutting amount) removed from a tile by various example wheels.
FIG. 2 shows a bar graph of mass loss from various example wheels.
FIG. 3 shows a bar graph of diamond efficiency index for various example wheels.

  Referring to FIG. 1, which shows the total cutting amount of each wheel, Example 1 shows the minimum cutting amount of the tested PEEK-containing formulation because there is no spherical filler to destabilize. Is noted. For this reason, the tough PEEK matrix was not destabilized so as to promote disassembly and exposure of new diamonds.

  Of the two PPS-containing formulations tested (Examples 2 and 9), it can be seen from FIG. 1 that the total cuts are very similar for each, but FIG. Indicates that there is a loss. Example 9 contains a coupling agent, but Example 2 does not contain it. The observed similarity in total cut for each suggests that the coupling agent does not promote retention of diamond in the PPS formulation. However, the increased wheel loss of the PPS containing formulation containing the coupling agent suggests that the coupling agent did not bind well to the spherical S60 filler and was lost during use.

  Example 6 is seen to increase the amount of cutting compared to Example 5, and Example 6 does not contain PEEK as much as Example 5, which tends to decompose more easily than Example 5, Is due to the presence of microspheres that help weaken the PEEK matrix.

  The opposite effect is observed for formulations containing PTS as an additive. Here, it can be seen that the sample with increased PEEK content (Example 3) increases the amount of cutting compared to Example 4. During the test, the coolant has a dark turbid gray appearance, indicating that the wheel is decomposing and losing the microsphere filler. This is concluded because PEEK is a light color but the microsphere filler is dark gray. The destabilization of PEEK in Example 5 is theoretically thought to be because the silanized filler does not bind to the PEEK resin, which substantially gives a similar effect to the presence of porosity.

  As the comparison between Example 6 and Example 8 shows, the formulation containing the coupling agent (Example 6) shows an increase in the total amount of cutting. This suggests that in PEEK formulations, coupling agents help in diamond retention in addition to serving as processing aids.

  The result shown in FIG. 2 is directly proportional to the result shown in FIG. 1 due to the fact that the formulation must decompose itself to continuously expose new diamonds in order to show high material removal. is doing.

  Example 1 shows a low level of wheel loss because there is no spherical filler to weaken the PEEK matrix. Therefore, the total amount of cutting is also low (FIG. 1).

  Similar to Example 1, Example 10 also exhibits a relatively low value of wheel loss, probably due to the reduced level of destabilization provided by glass bubbles, which are smaller, hollow glass spheres. This suggestion is supported by the increased wheel loss observed for all of the examples containing larger microspheres. Further, Example 7 (which has a slightly larger average particle size than microspheres and contains microbeads) has a slightly higher wheel loss (and correspondingly slightly increased total) than Example 5 which contains the same amount of PEEK. It can be seen that the cutting amount is shown. This further suggests that the size of the spherical filler plays an important role in destabilizing the PEEK matrix.

  In the case of Examples 3 and 4 (using PTS as the coupling agent) there is an interesting phenomenon, Example 3 has a higher proportion of PEEK than in Example 4, but Example 3 has a higher amount. There is a wheel loss. As described above, it is theoretically conceivable that PTS is bonded to the microsphere but not to the PEEK base material. This then causes loss of microspheres during use, leading to an increase in wheel wear rate. In effect, the theoretically considered failure of the microspheres to bind to the PEEK matrix is equivalent to the presence of wheel porosity.

  In order to gain a further quantifiable understanding of wheel behavior, material removal and wheel mass loss are very important parameters from a performance standpoint, and the “Diamond Efficiency Index” was evaluated.

  Briefly, the diamond efficiency index is the mass of tile removed per equigram of diamond and is calculated based on the diamond concentration information in each formulation.

  Since formulations that result in high material removal rates often cause high levels of wear or mass loss, material removal or wheel loss information itself is not sufficient to describe the performance of the formulation. is there.

  Similarly, formulations with a low index of wheel loss typically result in low material removal, and this formulation can certainly be very long in use, but is unlikely to meet material removal requirements .

  From FIG. 3, it can be seen that Example 1 provides a high diamond efficiency index, however, when combined with the data of FIGS. 1 and 2, it is clear that this is due to low material removal and low wheel loss. To be. This case is similar to Example 4.

  Examples 6, 5 and 7 both have a relatively high diamond efficiency index, and examination of the data in FIG. 1 shows that they each result in a relatively high material removal.

  Example 4 has a high diamond efficiency index, but examples 3 and 4 have very different properties because it also results in low material removal. Conversely, Example 3 provides high material removal, but this is at the expense of wheel mass loss, as evidenced by the lower diamond efficiency index.

  Examples 1-13 have an improved diamond efficiency index compared to the standard and are therefore apparently a higher efficiency diamond use.

4 is a bar graph of mass (cutting amount) removed from a tile by wheels of various examples. 4 is a bar graph of mass loss from various example wheels. 2 is a bar graph of diamond efficiency index for various example wheels.

Claims (30)

Superabrasive grains,
A thermoplastic polymer having a processing temperature of at least 280 ° C .;
A composition comprising a filler,
A composition wherein the thermoplastic polymer is present in an amount sufficient to bind the composition and the filler comprises spherical particles present in an amount of at least 40 volume percent of the composition.   The composition of claim 1, wherein the superabrasive grains are selected from the group consisting of diamond, cubic boron nitride, and mixtures thereof.   The composition of claim 1 or 2, wherein the superabrasive grains have an average particle size in the range of at least 50 micrometers to 150 micrometers.   4. The composition of claim 3, wherein the superabrasive grains have an average particle size in the range of at least 90 micrometers to 105 micrometers.   The composition of claim 1, wherein the superabrasive grains comprise diamond aggregates.   The composition of claim 1, wherein the superabrasive grains are present in a range of at least 2.5 volume percent to 20 volume percent of the composition.   The composition of claim 6, wherein the superabrasive grain is present at about 5 volume percent of the composition.   The thermoplastic polymer is from polyetheretherketone, polyetherketone, polyaryletherketone, polyaryletheretherketone, poly (amide-imide), polyphenylene sulfide, liquid crystal polymer, polyetherimide, polyimide, and mixtures thereof. The composition of claim 1, wherein the composition is selected from the group consisting of:   9. A composition according to claim 8, wherein the thermoplastic polymer is a polyetheretherketone.   The composition of claim 1, wherein the thermoplastic polymer is present in an amount of at least 20 volume percent of the composition.   11. The composition of claim 10, wherein the thermoplastic polymer is present in an amount of at least 30 volume percent of the composition.   The composition of claim 1, wherein the thermoplastic polymer is present in an amount of at least 35 volume percent of the composition.   The composition of claim 1, wherein the spherical filler particles are present in an amount of at least 45 volume percent of the composition.   12. The composition of claim 11, wherein the spherical filler particles are present in an amount of at least 50 volume percent of the composition.   The composition of claim 1, wherein the spherical filler particles are selected from the group consisting of glass spheres, ceramic spheres, calcium carbonate spheres, and mixtures thereof.   The composition of claim 15, wherein the spherical filler particles comprise soda lime-borosilicate glass spheres.   The composition of claim 15, wherein the spherical filler particles comprise silica-alumina ceramic spheres.   The composition of claim 1, wherein the spherical filler particles have an average particle size of at least 10 micrometers.   The composition of claim 1, wherein the spherical filler particles have an average particle size in the range of 10 to 2000 micrometers.   20. The composition of claim 19, wherein the spherical filler particles have an average particle size in the range of 25-50 micrometers.   The composition of claim 1, further comprising a coupling agent selected from the group consisting of organosilanes, zircoaluminates, zirconates and titanates.   24. The composition of claim 21, wherein the coupling agent is present in an amount of at least 0.1 weight percent to 2 weight percent of the filler.   23. A composition according to claim 21 or 22, wherein the coupling agent is in the form of a particulate solid.   The composition according to claim 1, suitable for injection molding at a temperature of at least 280 ° C. to 400 ° C.   25. A bonded abrasive product comprising a plurality of abrasive grains bonded together by a bonding medium to a shaped mass formed from the composition of any one of claims 1-24.   26. In the form of one of an abrasive wheel, a polishing bar, a saw blade, a cutting stick, a mounted point, a snagging wheel, a turning tool, a cup wheel, a center indented grinding wheel, a grinding wheel, or a flap wheel. Bonded abrasive product as described in 1.   26. A bonded abrasive product according to claim 25 in the form of a grinding wheel. Providing the composition of claim 1;
Heating the composition at a temperature in the range of 280 ° C. to 400 ° C. to provide a heated composition;
Injecting the heated composition into a mold;
Cooling the heated composition to provide a bonded abrasive article.   29. A method for manufacturing a bonded abrasive article according to claim 28, further comprising the step of heating the mold at a temperature in the range of at least 150C to 250C prior to injection.   30. A method for producing a bonded abrasive article according to claim 28 or 29, wherein the injection pressure is in the range of at least 70 MPa to 210 MPa.

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