US 11,993,722 B2
Twice recycled polymer powder composition for additive manufacturing including PEKK, siloxane and carbon fiber
Whitney Kline, Ellington, CT (US); Alden Winn, Glastonbury, CT (US); and Lawrence Varholak, Southbury, CT (US)
Assigned to Hexcel Corporation, Stamford, CT (US)
Filed by Hexcel Corporation, Stamford, CT (US)
Filed on May 24, 2019, as Appl. No. 16/422,283.
Prior Publication US 2020/0369898 A1, Nov. 26, 2020
Int. Cl. C09D 11/102 (2014.01); B29C 64/153 (2017.01); B29C 64/20 (2017.01); B29K 71/00 (2006.01); B33Y 10/00 (2015.01); B33Y 30/00 (2015.01); B33Y 70/00 (2020.01); C09D 11/037 (2014.01)
CPC C09D 11/102 (2013.01) [B29C 64/153 (2017.08); B33Y 10/00 (2014.12); B33Y 70/00 (2014.12); C09D 11/037 (2013.01); B29C 64/20 (2017.08); B29K 2071/00 (2013.01); B33Y 30/00 (2014.12)] 10 Claims
OG exemplary drawing
 
1. A powder composition suitable for use in selective laser sintering for printing a three-dimensional object, the powder composition comprising:
a first fraction comprising a recycled polyetherketoneketone (PEKK) powder having a plurality of PEKK particles, the plurality of PEKK particles having a mean diameter between 30 μm to 90 μm;
a second fraction comprising a siloxane powder having a plurality of siloxane particles;
a third fraction comprising carbon fiber, the third fraction is between 5% and 25% of the composition by weight;
wherein the recycled PEKK powder has been previously used in a first SLS build having a bed temperature between an upper melting point of the PEKK before the first SLS build (TM1) and 20° C. less than TM1;
wherein the recycled PEKK powder has been previously used in a second SLS build having a bed temperature between an upper melting point of the PEKK after the first SLS build and before the second SLS build (TM2) and 20° C. less than TM2;
wherein the plurality of siloxane particles having a mean diameter between 30 μm to 60 μm;
wherein the second fraction is between 0.5% and 1.5% of the composition by weight.