Polysiloxane-Based Polyurethanes with High Strength and Recyclability

Abstract

Polysiloxanes have attracted considerable attention in biomedical engineering, owing to their inherent properties, including good flexibility and biocompatibility. However, their low mechanical strength limits their application scope. In this study, we synthesized a polysiloxane-based polyurethane by chemical copolymerization. A series of thermoplastic polysiloxane-polyurethanes (Si-TPUs) was synthesized using hydroxyl-terminated polydimethylsiloxane containing two carbamate groups at the tail of the polymer chains 4,4′-dicyclohexylmethane diisocyanate (HMDI) and 1,4-butanediol as raw materials. The effects of the hard-segment content and soft-segment number average molecular weight on the properties of the resulting TPUs were investigated. The prepared HMDI-based Si-TPUs exhibited good microphase separation, excellent mechanical properties, and acceptable repeatable processability. The tensile strength of SiTPU-2K-39 reached 21.5 MPa, which is significantly higher than that of other flexible polysiloxane materials. Moreover, the tensile strength and breaking elongation of SiTPU-2K-39 were maintained at 80.9% and 94.6%, respectively, after three cycles of regeneration. The Si-TPUs prepared in this work may potentially be used in gas separation, medical materials, antifouling coatings, and other applications.

Plasma-Activated Polydimethylsiloxane Microstructured Pattern with Collagen for Improved Myoblast Cell Guidance

“…The pristine microstructure foil had a contact angle of 109°, the plasma-treated PDMS foil exhibited a contact angle of 24°, and the plasma-treated PDMS microstructure with collagen had a contact angle of 54°; these results are also in good agreement with Keffalinou et al [ 90 ]. Wettability-patterned surfaces prepared by an Atmospheric-Pressure Plasma Jet were used in microfluidic devices [ 91 ], and wettability also has a significant impact on microchannels in enhancing droplet coalescence and demulsification [ 92 ] and surface activation of polymer blends for recyclability [ 93 ].…”

On the State of Graphene Oxide Nanosheet in a Polyurethane Matrix

“…It can be observed that the surface C/O ratio was almost two times higher than the volume ratio for both the initial PU and the composites. In principle, surface segregation in PUs is a well-known phenomenon (for example, see [ 23 , 24 , 25 , 26 , 27 , 28 , 31 , 32 , 33 , 34 ]). In the case of our study, the surface C/N ratio changed symbatically with the change in the GO concentration, while the volume ratio remained almost constant ( Figure 1 ).…”

Performance characterization and biocompatibility assessment of silicone polyurethanes for polymer heart valve applications

“…Silicone polymers have lower intermolecular forces, so an excessive amount of silicone can reduce the mechanical strength of the material, consistent with our surface analysis results. Additionally, an excess of silicone may reduce material compatibility, thereby affecting its phase separation and, consequently, 29 its mechanical performance.…”