Use of a thermosetting polymeric powder composition
The present invention relates to the use of a thermosetting polymeric powder composition in a 3D printing process to produce a 3D duroplast, wherein the composition comprises at least one curable polymeric binder material and at least one thermoplast having a T g and/or M p below the temperature provided in a pass of the printing process and wherein during each pass of the printing process said polymeric binder material is at least partially cured within the layer thus formed and also at least partially crosslinked with the previous layer. The invention furthermore relates to a 3D printing process using such a thermosetting polymeric powder composition and a 3D-printing product obtained when using such a thermosetting polymeric powder composition.
1. A 3D printing process comprising: depositing layers of a 3D printing composition in multiple passes with a 3D printer to produce a 3D duroplast, wherein the 3D printing composition is provided as a thermosetting polymeric powder composition comprising:
at least one curable polymeric binder material in an amount of up to 98 wt % of the total composition; and at least one thermoplast, having a T g and/or M p below the temperature provided in each pass of the printing process, in an amount of between 1 and 30 wt % of the total composition; and wherein during each subsequent pass following the initial pass of the printing process, said at least one curable polymeric binder material is at least partially cured within the layer thus formed and also at least partially crosslinked with the previous layer.
2. The method according to claim 1 , wherein at least one thermoplast present in the composition has functional groups able to react with the at least one curable polymeric binder material.
3. The method according to claim 1 , wherein the at least one thermoplast is present in an amount of between 5 and 20 wt % of the total composition.
4. The method according to claim 1 , wherein the composition further comprises at least one member of the group consisting of curing agent, catalyst, initiator, and mixtures thereof, which member is able to cure said at least one curable polymeric binder material.
5. The method according to claim 1 , wherein the at least one curable polymeric binder material is curable by polyaddition, and/or polycondensation and/or radical polymerization.
6. The method according to claim 1 , wherein the at least one curable polymeric binder material is selected from compounds with at least two epoxy functional groups, compounds with at least two carboxylic acid functional groups, compounds with at least two hydroxyl functional groups, compounds derived from acrylic acid or methacrylic acid and mixtures thereof.
7. The method according to claim 1 , wherein the at least one curable polymeric binder material is present in an amount of from 10 to 70 wt % of the total composition.
8. The method according to claim 1 , wherein at least one thermoplast present in the composition has a melting temperature of between 50° C. and 200° C.
9. The method according to claim 1 , wherein at least one thermoplast present in the composition has a melt viscosity of 10 to 500 Pas when tested according to ISO 1133 at 160° C. using a 2.16 Kg load.
10. The method according to claim 1 , wherein at least one thermoplast present in the composition is a pure amorphous thermoplastic material with a T g below 90° C.
11. The method according to claim 1 , wherein at least one curable polymeric binder material present in the composition is an amorphous polymer binder.
12. The method according to claim 1 , wherein the thermosetting polymeric powder composition has a particle size of 1 to 250 μm.
13. The method according to claim 1 , wherein the glass transition temperature of the at least one curable polymeric binder material is at least 40° C.
14. The method according to claim 1 , wherein the at least one curable polymeric binder material has a number average molecular weight of 1,000 to 15,000 D.