Thermoplastic Polythiourethanes for 3D Printing

Patent Title: THIOURETHANE POLYMERS, METHOD OF SYNTHESIS THEREOF AND USE IN FUSED FILAMENT FABRICATION PRINTING

 Number/Link:  WO2018/035102

Applicant/Assignee:  University of Texas

Publication date: 22 February 2018

Gist”: Polythiourethanes from diisocyanates and dithiols are used in FFF printing

Why it is interesting: Fused Filament Fabrication (FFF), which is actually the same thing as  Fused Deposition Modeling (FDM) is a popular and cheap additive manufacturing technology in which a thermoplastic filament is molten and ‘printed’ in layers. Many off-the-shelf thermoplastics can be used in FFF but these often do not have the correct melt characteristics resulting in printed objects of poor quality. According to this invention FFF-optimized thermoplastics can be prepared by reacting dithiols with diisocyanates into polythiourethanes.  The reaction is carried out in an aprotic solvent and catalysed by a non-nucleophilic base. In an example 2,2′-(ethylenedioxy)diethanethiol is reacted with HDI in DMF and catalysed by triethylamine. FFF printed parts of this polymer are said to show high toughness and less water uptake compared to TPU and polyamides.

polythiourethane

Polythiourethane according to the invention

 

Urethane-Acrylate Hybrids From Thiol-Ene Chemistry

Title: POLYURETHANE (METH) ACRYLATES USING MODIFIED HYDROXYTHIOLS

 Number/Link: US2015/0232422

Applicant/Assignee: Dymax Oligomers and Coatings

Publication date: 20-08-2015

Gist”: A dihydroxythiol is reacted with an acrylate and then with diisocyanate and hydroxyacrylate

Why it is interesting: This invention relates to radically polymerizable urethane oligomers which are useful as adhesives or coatings. The oligomers are prepared in two stages:  first a dihydroxy thiol is reacted with an acrylate resulting in a diol which is then reacted with an excess diisocyanate and then with hydroxyacrylates.  For example: thioglycerol is reacted with phenyltioethylacrylate.  The resulting diol is then further reacted with TDI and subsequently with polycaprolactonacrylate and hydroxyethylacrylate resulting in the structure below. The urethane oligomers can be used for coatings or adhesives which are said to have improved properties over the existing art, like improved thermal resistance.

A urethane-acrylate oligomer according to the invention

A urethane-acrylate oligomer according to the invention