Title: METHODS OF USING THERMOPLASTIC POLYURETHANES IN FUSED DEPOSITION MODELING AND SYSTEMS AND ARTICLES THEREOF .
Number/Link: WO2015/109141
Applicant/Assignee: Lubrizol
Publication date: 23-07-2015
“Gist”: TPU with specific crystallization temperature and modulus retention can be used for fused deposition modeling
Why it is interesting: Additive manufacturing in all its forms has been a steadily growing trend over the last few years. Many different materials have been used in these processes, but the use of thermoplastic polyurethane has proven to be difficult because of its low crystallization rate, broad melting range and challenging melt-viscosity control. According to this application TPU can be used for fused deposition modeling (“3D printing” by extruding molten thermoplastics) when it has a crystallization temperature of about 115°C and retains its shear modulus well with temperature. Examples of such TPUs have a high harblock content (about 50%) and a molar ratio of chain extender to polyol of 2 to about 4, and are prepared from 4,4′-MDI, butandiol and 2000 MW PTMEG polyether or butylene-adipate polyester diols.