Abrasive composition and articles incorporating same

Claim 2

A bonded abrasive composition comprising: a) a cured smear-resistant and wear-resistant elastomeric polyurea binder matrix having urea linkages, the binder matrix selected from the group consisting of; 1) the reaction product of a first polyfunctional amine having an average functionality of 2 and an equivalent weight of at least about 300, said first polyfunctional amine being capable on polymerization of forming a first soft segment, and a polyfunctional isocyanate having an average isocyanate functionality of at least 2 and an equivalent weight of less than about 300, said poly functional isocyanate being capable on polymerization of forming a first hard segment; and 2) the reaction product of a polyfunctional isocyanate prepolymer having a functionality of at least 2 and having an equivalent weight of at least about 300, said polyfunctional isocyanate prepolymer being capable on polymerization of forming a second soft segment, and a second polyfunctional amine having an average functionality of at least 2 and an equivalent weight of less than about 300, said second polyfunctional amine being capable on polymerization of forming a second hard segment; and, b) an effective amount of abrasive particles dispersed throughout said binder matrix.

Claim 3

A bonded abrasive composition in accordance with claim 1, said composition having no more than about 20 percent of said urea linkages substituted with urethane linkages.

Claim 4

A bonded abrasive composition in accordance with claim 1, wherein said first polyfunctional amine is an oligomeric aromatic polyfunctional amine having the formula: ##STR5## wherein n is an integer ranging from 2 to 4; each x is 1 or 2; each phenyl nucleus is para-amino, meta-amino, or di- meta-amino substituted; each Z is selected from the group consisting of ##STR6## each R is hydrogen or lower alkyl of 4 carbon atoms or less; and G is an n-valent radical which may be obtained by the removal of hydroxyl or amino groups, respectively, from an n-valent polyol or polyamine having an equivalent weight ranging from about 300 to about 3000.

Claim 5

A bonded abrasive composition in accordance with claim 1 wherein said abrasive particles are preformed agglomerates of individual abrasive particles.

Claim 6

A bonded abrasive composition in accordance with claim 4 having sufficient void volume so that said composition has a density ranging from about 1.0 to about 3.0 g/cm 3 .

Claim 7

In an abrasive-loaded device suitable for being removably mounted on a tool, the device having a shaped body of elastomeric material having dispersed therein an effective amount of abrasive particles, said shaped body being suitable for grinding, deburring, finishing and sanding, and having means for removably mounting said shaped body on a tool, the elastomeric material comprising a smear-resistant and wear-resistant elastomeric polyurea binder matrix having urea linkages, the binder matrix selected from the group consisting of: (1) the reaction product of a first polyfunctional amine having an average functionality of 2 and an equivalent weight of at least about 300, said first polyfunctional amine being capable on polymerization of forming a first soft segment, and a polyfunctional isocyanate having an average isocyanate functionality of at least 2 and an equivalent weight of less than about 300, said polyfunctional-isocyanate being capable of polymerization of forming a first segment, and (2) the reaction product of a polyfunctional isocyanate prepolymer having a functionality of at least 2 and having an equivalent weight of at least about 300, said polyfunctional isocyanate prepolymer being capable on polymerization of forming a second soft segment, and a second polyfunctional amine having an average functionality of at least 2 and an equivalent weight of less than about 300, said second polyfunctional amine being capable on polymerization of forming a second hard segment.

Claim 8

In an abrasive-loaded device suitable for being removably mounted on a tool, the device having a shaped body of elastomeric material having dispersed therein an effective amount of abrasive particles, said shaped body being suitable for grinding, deburring, finishing and sanding, and having means for removably mounting said shaped body on a tool, the elastomeric material comprising a smear-resistant and wear-resistant elastomeric polyurea binder matrix having urea linkages, the binder matrix selected from the group consisting of: (1) the reaction product of a first polyfunctional amine having an average functionality of 2 and an equivalent weight of at least about 300, said first polyfunctional amine being capable on polymerization of forming a first soft segment, and a polyfunctional isocyanate having an average isocyanate functionality of at least 2 and an equivalent weight of less than about 300, said polyfunctional-isocyanate being capable of polymerization of forming a first segment, and (2) the reaction product of a polyfunctional isocyanate prepolymer having a functionality of at least 2 and having an equivalent weight of at least about 300, said polyfunctional isocyanate prepolymer being capable on polymerization of forming a second soft segment, and a second polyfunctional amine having an average functionality of at least 2 and an equivalent weight of less than about 300, said second polyfunctional amine being capable on polymerization of forming a second hard segment.

Claim 9

An abrasive-loaded device in accordance with claim 6, said binder matrix having no more than about 20 percent of said urea linkages substituted with urethane linkages.

Claim 10

An abrasive-loaded device in accordance with claim 6, said shaped body being in the form of a wheel.

Claim 11

An abrasive-loaded device in accordance with claim 6, said article including a backing material to which the shaped body is attached.

Claim 12

An abrasive-loaded device in accordance with claim 9, said backing comprising: (a) a tough, heat resistant, thermoplastic binder material; and (b) an effective amount of a fibrous reinforcing material distributed throughout the tough, heat resistant, thermoplastic binder material; wherein the tough, heat resistant, thermoplastic binder material and fibrous reinforcing material together comprise a hardened composition that will not substantially deform or disintegrate under abrading conditions.

Claim 13

The abrasive-loaded device of claim 10 wherein: (a) the tough, heat resistant, thermoplastic binder material has a melting point of at least 200° C.; and (b) the fibrous reinforcing material is in the form of individual fibers with a melting point at least 25° C. above the melting point of the tough, heat resistant, thermoplastic binder material.

Claim 14

The abrasive-loaded device of claim 10 wherein the tough, heat resistant, thermoplastic binder material is present in an amount of 60-99 wt-%, based upon the weight of the backing.

Claim 15

The abrasive-loaded device of claim 10 further including a molded-in attachment system.

Claim 16

The abrasive-loaded device of claim 13 wherein the backing is in the shape of a disc and the attachment system is located in the center of the disc.

Claim 17

The abrasive-loaded device of claim 10 wherein the back surface of the backing has ribs molded therein, the ribs being molded into the back surface of the backing in a radial pattern.

Claim 18

The abrasive-loaded device of claim 10 wherein the backing has an edge region and a center region; said edge region being of increased thickness relative to said center region.

Claim 19

A method of making the abrasive-loaded device of claim 10, the method comprising the steps of: (a) combining a tough, heat resistant, thermoplastic binder material and an effective amount of a fibrous reinforcing material such that the fibrous reinforcing material is distributed throughout the tough, heat resistant, thermoplastic binder, to form a softened, moldable, mixture; (b) applying the softened, moldable mixture to the shaped body; and (c) subjecting the softened, moldable mixture to conditions sufficient to harden the thermoplastic

Claim 20

Method in accordance with claim 17 wherein said applying step is achieved by injection molding.

Claim 23

A method in accordance with claim 19 which further comprises introducing said curable abrasive mixture into a mold prior to curing the mixture to form said bonded abrasive composition.

Claim 24

A method in accordance with claim 19 wherein said first polyfunctional amine is an oligomeric aromatic polyfunctional amine having the formula: ##STR7## wherein n is an integer ranging from 2 to 4; each x is 1 or 2; each phenyl nucleus is para-amino, meta-amino, or di- meta-amino substituted; each Z is selected from the group consisting of ##STR8## each R is hydrogen or lower alkyl of 4 carbon atoms or less; and G is an n-valent radical which may be obtained by the removal of hydroxyl or amino groups, respectively, from an n-valent polyol or polyamine having an equivalent weight ranging from about 300 to about 3000.

Claim 25

An abrasive article comprising: (A) a bonded abrasive composition comprising: 1) a cured smear-resistant and wear-resistant elastomeric polyurea binder matrix having urea linkages, the binder matrix selected from the group consisting of; a) the reaction product of a first polyfunctional amine having an average functionality of 2 and an equivalent weight of at least about 300, said first polyfunctional amine being capable on polymerization of forming a first soft segment, and a polyfunctional isocyanate having an average isocyanate functionality of at least 2 and an equivalent weight of less than about 300, said poly functional isocyanate being capable on polymerization of forming a first hard segment; and b) the reaction product of a polyfunctional isocyanate prepolymer having a functionality of at least 2 and having an equivalent weight of at least about 300, said polyfunctional isocyanate prepolymer being capable on polymerization of forming a second soft segment, and a second polyfunctional amine having an average functionality of at least 2 and an equivalent weight of less than about 300, said second polyfunctional amine being capable on polymerization of forming a second hard segment; and, 2) an effective amount of abrasive particles dispersed throughout said binder matrix, said composition integrally molded to a backing comprising B) a tough, heat resistant, thermoplastic binder material and an effective amount of a fibrous reinforcing material distributed throughout the tough, heat resistant, thermoplastic binder material; wherein the tough, heat resistant, thermoplastic binder material and fibrous reinforcing material together comprise a hardened composition that will not substantially deform or disintegrate under abrading conditions.

Claim 26

An abrasive article comprising: (A) a bonded abrasive composition comprising: 1) a cured smear-resistant and wear-resistant elastomeric polyurea binder matrix having urea linkages, the binder matrix selected from the group consisting of; a) the reaction product of a first polyfunctional amine having an average functionality of 2 and an equivalent weight of at least about 300, said first polyfunctional amine being capable on polymerization of forming a first soft segment, and a polyfunctional isocyanate having an average isocyanate functionality of at least 2 and an equivalent weight of less than about 300, said poly functional isocyanate being capable on polymerization of forming a first hard segment; and b) the reaction product of a polyfunctional isocyanate prepolymer having a functionality of at least 2 and having an equivalent weight of at least about 300, said polyfunctional isocyanate prepolymer being capable on polymerization of forming a second soft segment, and a second polyfunctional amine having an average functionality of at least 2 and an equivalent weight of less than about 300, said second polyfunctional amine being capable on polymerization of forming a second hard segment; and, 2) an effective amount of abrasive particles dispersed throughout said binder matrix, said composition integrally molded to a backing comprising B) a tough, heat resistant, thermoplastic binder material and an effective amount of a fibrous reinforcing material distributed throughout the tough, heat resistant, thermoplastic binder material; wherein the tough, heat resistant, thermoplastic binder material and fibrous reinforcing material together comprise a hardened composition that will not substantially deform or disintegrate under abrading conditions.