MASTERBATCH COMPRISING BORON NITRIDE, COMPOSITE POWDERS THEREOF, AND COMPOSITIONS AND ARTICLES COMPRISING SUCH MATERIALS
A masterbatch composition comprises a composite of a polymer resin material and boron nitride. The masterbatch composition can be in the form of a powder or particles. The masterbatch composition can impart improved properties such as wear resistance, thermal conductivity, compressibility, etc., to a composition or article formed from the masterbatch composition. In one embodiment, the masterbatch composition can be used to form a brake pad composition and provides a brake pad with improved properties compared to a composition formed by dry blending the separate boron nitride and resin materials.
1 . An article comprising a composition disposed on a surface thereof, the composition including (i) a base material, and (ii) a masterbatch composition of (a) a boron nitride material and (b) a polymer resin material.
2 . The article of claim 1 , wherein the article is formed from the composition.
3 . The article of claim 1 , wherein the base material is a nonasbestos organic formulation, a low metallic resin bonded formulation, or a semi-metallic resin bonded formulation.
4 . The article of claim 1 comprising from about 0.1 weight percent to about 10 weight percent of boron nitride.
5 . The article of claim 1 comprising from about 1 weight percent to about 8 weight percent of boron nitride.
6 . The article of claim 1 comprising from about 2.5 weight percent to about 7.5 weight percent.
7 . The article of claim 1 comprising from about 0.1 weight percent to about 7.5 weight percent of copper.
8 . The article of claim 1 , wherein the article has 0.5 weight percent or less of copper.
9 . The article of claim 1 , wherein the article is a brake pad.
10 . The article of claim 9 having a μ14 value that is up to 35% greater than that of an article comprising a similar concentration of boron nitride and/or copper formed from a dry blend.
11 . The article of claim 9 having a μ14 value that is about 10% to about 35% greater than that of an article comprising a similar concentration of boron nitride and/or copper formed from a dry blend.
12 . The article of claim 9 having pad thickness loss after SAE J2522 test that is up to 65% lower than that of an article comprising the same concentration of boron nitride and/or copper provided from a dry blend.
13 . The article of claim 9 having pad thickness loss after SAE J2522 test that is about 10% to about 65% lower than that of an article comprising the same concentration of boron nitride and/or copper provided from a dry blend.
14 . The article of claim 1 , wherein the polymer resin material comprises a phenol formaldehyde resin.
15 . The article of claim 1 , wherein the polymer resin material is a novolac resin.
16 . A brake pad comprising a friction composition, the friction composition comprising boron nitride and having 0.5 weight percent or less of copper.
17 . The brake pad of claim 16 , wherein the friction composition comprises from about 0.1 weight percent to about 10 weight percent of boron nitride.
18 . The brake pad of claim 16 , wherein the friction composition comprises from about 1 weight percent to about 8 weight percent of boron nitride.
19 . The brake pad of claim 16 , wherein the friction composition comprises from about 2.5 weight percent to about 7.5 weight percent of boron nitride.
20 . The brake pad of claim 16 , wherein the boron nitride in the friction composition is added as part of a masterbatch composition comprising the boron nitride and a polymer resin.
21 . The brake pad of claim 20 , wherein the polymer resin is chosen from a phenol formaldehyde or an epoxy modified phenol formaldehyde.
22 . The brake pad of claim 16 , wherein the brake pad has a disc thickness loss after SAE J2522 test that is up to 35% lower than that of a brake pad that comprises copper and is substantially free of boron nitride based on SAE J2522 test.
23 . The brake pad of claim 16 , wherein the brake pad has a SAE J2521 noise index that is up to 2 points higher than that of an article that comprises copper and is substantially free of boron nitride.