Facile Preparation of Highly Stretchable and Recovery Peptide-Polyurethane/Ureas

Abstract

Abstract:In this work, a new class of highly stretchable peptide-polyurethane/ureas (PUUs) were synthesized containing short β-sheet forming peptide blocks of poly(γ-benzyl-L-glutamate)-bpoly(propylene glycol)-b-poly(γ-benzyl-L-glutamate) (PBLG-b-PPG-b-PBLG), isophorone diisocyanate as the hard segment, and polytetramethylene ether glycol as the soft phase. PBLG-b-PPG-b-PBLG with short peptide segment length (<10 residues) was synthesized by amine-initiated ring opening polymerization of γ-benzyl-L-glutamate-N-carboxyanhydrides (BLG-NCA), which shows mixed α-helix and β-sheet conformation, where the percent of β-sheet structure was above 48%. Morphological studies indicate that the obtained PUUs show β-sheet crystal and nanofibrous structure. Mechanical tests reveal the PUUs display medium tensile strength (0.25-4.6 MPa), high stretchability (>1600%), human-tissue-compatible Young's modulus (226-513 KPa). Furthermore, the shape recovery ratio could reach above 85% during successive cycles at high strain (500%). In this study, we report a facile synthetic method to obtain highly stretchable and recovery peptide-polyurethane/urea materials, which will have various potential applications such as wearable and implantable electronics, and biomedical devices.

Rapid Synthesis of Silk-Like Polymers Facilitated by Microwave Irradiation and Click Chemistry

“…The spacings and broadness of these additional peaks are consistent with antiparallel β-sheet domains reported for spidroin from N. clavipes − and other synthetic silk-mimetic polymers that incorporate oligo­(alanine) segments. ,,,, Correspondingly, FTIR of P6_Click_microwave shows a strong signal in the Amide I region at 1625 cm –1 , which supports antiparallel β-sheet conformation, as well as a much weaker signal at 1657 cm –1 , which indicates α-helical or random coil structures. − , Importantly, these results indicate that formation of silk-like antiparallel β-sheet structures is not prevented by the non-natural triazole linkage in P6_Click_microwave that results from alkyne–azide click chemistry between PEG and peptide blocks.…”

“…17,18,20,21,66 Correspondingly, FTIR of P6_Click_microwave shows a strong signal in the Amide I region at 1625 cm −1 , which supports antiparallel β-sheet conformation, as well as a much weaker signal at 1657 cm −1 , which indicates α-helical or random coil structures. [17][18][19][20][21]67 Importantly, these results indicate that formation of silk-like antiparallel β-sheet structures is not prevented by the non-natural triazole linkage in P6_Click_microwave that results from alkyne−azide click chemistry between PEG and peptide blocks. Formation of β-sheet structures is less apparent in P3_Oxyma_microwave, which has amide linkages but is significantly lower in molecular weight.…”

1a3_0727_ Archetypes of Spider Silk

“…Similarly, Stretchable peptide-polyurethane were synthesized containing short β-sheet forming peptide blocks of poly(γ-benzyl-l-glutamate)-b-poly(propylene glycol)-b-poly(γbenzyl-l-glutamate) (PBLG-b-PPG-b-PBLG), isophorone diisocyanate as the hard segment, and polytetramethylene ether glycol as the soft phase( See Figure 2). Mechanical tests revealed the spider silk inspired polyurethanes displayed medium tensile strength (0.25-4.6 MPa), high stretchability (>1600%), human-tissue-compatible Young's modulus (226-513 KPa) [6].…”

Scalable Spider Silk Inspired Materials with High Extensibility and Super Toughness

“…Nature uses interesting strategies to produce biomaterials with high performance (such as stiffness, toughness, and scalability) by exploring hierarchical structures [4]. Inspection of natural structural proteins (such as silk, collagen and elastin) shows that the ordered structure of long-distance peptides plays a vital role in achieving excellent mechanical properties [5]. For example, spider silk achieves a perfect balance between strength and toughness due to its hierarchical structure including β-sheet, α-helix and random coil structures.…”