Particle comprising a matrix and a radical initiator
The invention pertains to a particle comprising a composition containing a matrix and a peroxide or azo radical initiator, wherein the particle is a fiber or fibrid selected from aramid, polyester, polyimide, cellulose, and glass. The invention further relates to particle-elastomers comprising said composition, and skim products, tires, tire treads, and belts comprising these particle-elastomers.
1. An aramid or cellulose fiber or fibrid at least partially coated with composition containing a matrix and a peroxide or azo radical initiator, wherein
the matrix is selected from a polyolefin, a wax, and a mixture thereof.
2. The aramid or cellulose fiber or fibrid of claim 1 wherein the radical initiator is a peroxide.
3. The aramid or cellulose fiber or fibrid of claim 2 wherein the radical initiator is a dialkyl peroxyketal, a dialkyl peroxide, a di(alkylperoxy)alkylene, a di(alkylperoxy)aralkylene, or a mixture thereof.
4. The aramid or cellulose fiber or fibrid of claim 3 wherein the radical initiator is 1,1-(tert-butylperoxy)- cyclohexane and/or 1,1-(tert-butylperoxy)-3,3,5-trimethylcyclohexane.
5. The aramid or cellulose fiber or fibrid of claim 1 wherein the composition comprises 5-98 wt % of the radical initiator, based on the weight of the composition.
6. The aramid or cellulose fiber or fibrid of claim 1 wherein the matrix is selected from an extrudable polymer, a wax, and a mixture thereof.
7. The aramid or cellulose fiber or fibrid of claim 6 wherein the extrudable polymer is a polyolefin selected from polyethylene and/or a derivative thereof, polypropylene and/or a derivative thereof, and a mixture thereof.
8. The aramid or cellulose fiber or fibrid of claim 6 wherein the wax is a saturated alkanecarboxylic acid ester having 12-50 carbon atoms, or a synthetic microcrystalline wax having a C22-C38 alkyl chain.
9. The aramid or cellulose fiber or fibrid of claim 8 comprising up to 85 wt % based on the weight of the particle at least one of stearyl stearate and palmityl stearate.
10. The aramid or cellulose fiber or fibrid of claim 1 wherein the fiber or fibrid is a poly(p-phenylene-terephthalamide) or a co-poly-(paraphenylene/3,4′-oxydiphenylene terephthalamide) fiber.
11. The aramid or cellulose fiber or fibrid of claim 1 wherein the fiber or fibrid is a continuous fiber, chopped fiber, staple fiber or pulp, optionally which is pre-treated with a sizing.
12. The aramid or cellulose fiber or fibrid of claim 1 wherein the composition amounts 5-90 wt %, based on the weight of the fiber or fibrid.