Self‐Healing Polyester Urethane Supramolecular Elastomers Reinforced with Cellulose Nanocrystals for Biomedical Applications

Abstract

Stretchable self-healing urethane-based biomaterials have always been crucial for biomedical applications; however, the strength is the main constraint of utilization of these healable materials. Here, a series of novel, healable, elastomeric, supramolecular polyester urethane nanocomposites of poly(1,8octanediol citrate) and hexamethylene diisocyanate reinforced with cellulose nanocrystals (CNCs) are introduced. Nanocomposites with various amounts of CNCs from 10 to 50 wt% are prepared using solvent casting technique followed by the evaluation of their microstructural features, mechanical properties, healability, and biocompatibility. The synthesized nanocomposites indicate significantly higher tensile modulus (approximately 36-500-fold) in comparison to the supramolecular polymer alone. Upon exposure to heat, the materials can reheal, but nevertheless when the amount of CNC is greater than 10 wt%, the self-healing ability of nanocomposites is deteriorated. These materials are capable of rebonding ruptured parts and fully restoring their mechanical properties. In vitro cytotoxicity test of the nanocomposites using human dermal fibroblasts confirms their good cytocompatibility. The optimized structure, self-healing attributes, and noncytotoxicity make these nanocomposites highly promising for tissue engineering and other biomedical applications.

Stimuli‐responsive polyurethane bionanocomposites of poly(ethylene glycol)/poly(ε‐caprolactone) and [poly(ε‐caprolactone)‐grafted‐] cellulose nanocrystals

“…G‐CNC(x) samples show an increasing trend in θ a . Despite of increasing CNCs' content, presence of PCL grafts increases the total content of PCL segments in the sample causing an increase in W ca and an increase in their hydrophobic nature 36 …”

“…and an increase in their hydrophobic nature. 36 F I G U R E 6 DMA analysis of the shape memory performance of the synthesized in situ PUs. PU, polyurethane…”

Covalent Adaptable Network and Self-Healing Materials: Current Trends and Future Prospects in Sustainability

“…The presence of CANs as crosslinkers can help to facilitate the recycling of lightly crosslinked polyesters. The chemistry of transesterification reactions involving polyesters has been reported by various researchers [ 16 , 51 , 52 , 53 , 54 , 55 , 56 ]. For example, Kotliar has reviewed three basic mechanisms through which the dynamic bonds of polyesters interchange [ 57 , 58 , 59 ].…”

Self-healing polyurethane elastomers based on charge-transfer interactions for biomedical applications

“…[11][12][13] Although elastomers are available as structural components of artificial tissues and organs and also coatings on them, in which hydrogels cannot be substitutes, to date, self-healable and biocompatible elastomers have rarely reported. [15][16][17][18][19][20][21][22][23][24] Here we report self-healable and cell-compatible polyurethane elastomers based on the charge-transfer (CT) interaction between electron-rich pyrene (Py) and electron-deficient naphthalene diimide (NDI) as a reversible interaction (Figure 1). 25 Unlike hydrogen bonding, one of the most common reversible bonds/interactions in self-healing polymers, 26,27 CT interactions are hardly affected by water molecules and promise to work in physiological conditions.…”