US 11,850,770 B2
Method for producing spherical thermoplastic polymer particles
Andreas Bauder, Ludwigshafen am Rhein (DE); Kerstin Muelheims, Ludwigshafen am Rhein (DE); Michael Freese, Lemfoerde (DE); and Achim Stammer, Ludwigshafen am Rhein (DE)
Assigned to BASF SE, Ludwigshafen am Rhein (DE)
Appl. No. 17/596,628
Filed by BASF SE, Ludwigshafen am Rhein (DE)
PCT Filed Jun. 18, 2020, PCT No. PCT/EP2020/066966
§ 371(c)(1), (2) Date Dec. 15, 2021,
PCT Pub. No. WO2020/254498, PCT Pub. Date Dec. 24, 2020.
Claims priority of application No. 19180876 (EP), filed on Jun. 18, 2019.
Prior Publication US 2022/0250283 A1, Aug. 11, 2022
Int. Cl. B29B 9/10 (2006.01); B29B 9/12 (2006.01); B29B 9/16 (2006.01); B33Y 10/00 (2015.01); B33Y 70/00 (2020.01); B33Y 80/00 (2015.01); B29C 64/153 (2017.01); B29C 48/36 (2019.01); C08J 3/16 (2006.01); B29K 75/00 (2006.01)
CPC B29B 9/10 (2013.01) [B29B 9/12 (2013.01); B29C 48/36 (2019.02); B29C 64/153 (2017.08); B33Y 10/00 (2014.12); B33Y 70/00 (2014.12); B33Y 80/00 (2014.12); C08J 3/16 (2013.01); B29B 2009/166 (2013.01); B29K 2075/00 (2013.01); C08J 2375/04 (2013.01)] 15 Claims
 
1. A process for producing particles of a thermoplastic polymer in spherical form, the process comprising:
(i) providing at least one thermoplastic polymer in a molten state;
(ii) providing an aqueous solution of at least one surface-active substance, wherein the aqueous solution of the at least one surface-active substance is at a temperature in a range from 100 to 300° C.;
(iii) dispersing the at least one thermoplastic polymer from (i) in the aqueous solution of the at least one surface-active substance from (ii), to obtain an aqueous solution comprising dispersed thermoplastic polymer;
(iv) cooling down the aqueous solution comprising dispersed thermoplastic polymer to a temperature below a solidification point of the at least one thermoplastic polymer, to obtain a suspension comprising an aqueous solution and particles of the at least one thermoplastic polymer suspended therein in a solid state, wherein the particles are in spherical form;
(v) separating the particles of the at least one thermoplastic polymer in spherical form from the suspension obtained in (iv); and
(vi) optionally, drying the particles of the at least one thermoplastic polymer in spherical form that have been separated off in (v);
wherein the particles of the at least one thermoplastic polymer in spherical form that have been separated off in (v) and optionally dried in (vi) have a particle size distribution having a d[4,3] value of more than 10 μm and a d90.3 value of more than 20 μm.