Melam granulate material and process for preparation thereof

Patent metadata

Field	Value
Publication number	US-9422270-B2
Application number	US-201113703479-A
Country	US
Kind code	B2
Filing date	Jun 7, 2011
Priority date	Jun 11, 2010
Publication date	Aug 23, 2016
Grant date	Aug 23, 2016

Abstract

The invention relates to a method for producing a free flowing flame retardant material, comprising steps of i. preparing an aqueous slurry from a freshly prepared moist melam having a water content of at least 8 wt. %, relative to the total weight of the moist melam, the slurry comprising water, melam and a water soluble polymeric binding agent, wherein the melam is present in an amount of 5-35 wt. % relative to the total weight of the slurry, and the water soluble polymeric binding agent is present in an amount of 0.5-8 wt. % relative to the total amount of melam and the water soluble polymeric binding agent; ii. drying the slurry in a fluid bed to form a granulate material; and iii. collecting the resulting granulate material. The invention also relates to a melam granulate material, obtainable by said process.

First claim

The invention claimed is:

1. A process for the preparation of a melam granulate material, the process comprising steps of:
(i) preparing an aqueous slurry from a freshly prepared moist melam having a water content of at least 8 wt. %, relative to the total weight of the moist melam, the slurry comprising water, melam and a water soluble polymeric binding agent, wherein the melam is present in an amount of 5-35 wt. % relative to the total weight of the slurry, and the water soluble polymeric binding agent is present in an amount of 0.5-8 wt. % relative to the total amount of melam and the water soluble polymeric binding agent;
(ii) drying the slurry in fluid bed to form a granulate material consisting of granules comprised of melam particles bonded to each other with the polymeric binding agent, wherein the granules have a median particle size (d50) in a range of 100-1000 μm; and
(iii) collecting the resulting granulate material.

2. The process according to claim 1 , wherein step (ii) comprises drying the granulate material to a water content of at most 12 wt. %, relative to the total weight of the granulate material.

3. The process according to claim 2 , wherein step (ii) comprises drying the granulate material to a water content of 0-6 wt. %, relative to the total weight of the granulate material.

4. The process according to claim 1 , wherein the median particle size (d50) of the granules is in the range of 200-900 μm.

5. The process according to claim 1 , wherein the granulate material has a mean particle size (d10) of at least 10 μm and/or a mean particle size (d90) of at most 3000 μm.

6. The process according to claim 1 , wherein the amount of the polymeric binding agent is in the range of 1-6 wt. %, relative to the total weight of the granulate material.

7. The process according to claim 1 , wherein the polymeric binding agent is at least one selected from the group consisting of polyvinyl alcohol, polyvinylpyrrolidone and polyvinylcaprolactam.

8. The process according to claim 1 , wherein the melam particles of the granulate material have a median primary particle size (d50) in a range of 0.1-50 μm.

9. The process according to claim 1 , wherein the granulate material obtained in step (ii) has a Carr-P bulk density in the range of 400-1000 kg/m 3 .

Assignees

• Kwant Gerard Jan
• Stoelwinder Christiaan Johannes Cornelis
• Van Laarhoven Bas
• Dsm Ip Assets Bv

Inventors

• Kwant Gerard Jan
• Stoelwinder Christiaan Johannes Cornelis
• Van Laarhoven Bas

Classifications

• C08J3/203

  Solid polymers with solid and/or liquid additives · CPC title

• B01J2/16

  by suspending the powder material in a gas, e.g. in fluidised beds or as a falling curtain · CPC title

• B01J2/30

  using agents to prevent the granules sticking together; Rendering particulate materials free flowing in general, e.g. making them hydrophobic · CPC title

• C08J3/03

  in aqueous media · CPC title

• C08K9/08

  Ingredients agglomerated by treatment with a binding agent · CPC title