Synthesis of Poly-(L-Lactic Acid) - Rice University
N2 - A novel nonnatural amino acid that carries a 2-anthraquinonyl group, L-2-anthraquinonylalanine, was first synthesized and converted to the corresponding N-carboxyanhydride (NCA). The NCA was polymerized to give poly(L-2-anthraquinonylalanine) in the form of a diblock copolymer with poly(ethylene glycol) that is linked to the C-terminal. A triblock copolymer was also prepared with poly(γ-benzyl L-glutamate)s that are attached to both N- and C-terminals. CD spectra of the diblock copolymer showed a helical conformation that is different from a right-handed α-helix. Conformational analysis and theoretical CD calculation suggested that the poly(anthraquinonylalanine) unit prefers a left-handed α-helix with the lowest energy side-chain orientation.
Synthesis of a Novel Poly(iptycene) Ladder Polymer | …
AB - Polyhydroxyalkanoates are a popular class of bioplastics valued for their rapid biodegradadion, biocompatibility, and renewable feedstocks. While there are already a few commercial applications for these biopolymers, a greater diversity of properties is needed to compete with petroleum based polymers. In this chapter, we report the synthesis and characterization of polyhdroxyoctanoate and its nanocomposite with thermally reduced graphene. The results indicate the incorporation of graphene into the PHO matrix leads to a small upshift in the glass transition, enhance the thermal stability, and ∼600% increase in modulus. Electrical percolation between 0.5 and 1 vol.% TRG was obtained.
We synthesized a library of 50 poly(ethylene glycol) (PEG) derivatives to expand the extent of conjugation with biologically active molecules (biopolymers, peptides, drugs, etc.) and biomaterial substrates. The formation of PEG derivatives was confirmed with HPLC, 1H and 13C NMR. PEG derivatives were polymerized into networks in order to study the role of PEG and terminal functional groups in modulating the hydrophilicity of biomaterials and cell−biomaterial interaction. The resulting surface hydrophilicity and the number of adhered fibroblasts were primarily dependent on the PEG concentration with the molecular weight and the terminal functional group of PEG derivatives being less important. One of PEG derivatives, PEG−bis-glutarate, was utilized to link peptide sequences to gelatin backbone in the formation of novel biomedical hydrogels. PEG−peptide conjugates were characterized by mass spectroscopy. PEG−peptide modified gelatins were characterized by gel permeation chromatography.