The hydrolytic degradation of fully cured polyester urethane networks polymerized in the presence of several weight ratios of triacetin was monitored by the residual concentration in elastically active chains obtained from modulus and equilibrium solvent swelling measurements.
The resulting cellulose/SA hydrogels were characterized by solid-state 13C NMR, wide-angle X-ray diffraction (WXRD), thermo-gravimetric analysis (TGA), scanning electron microscopy (SEM), rheological measurement, dynamic mechanical analysis (DMA) and swelling test to evaluate their structure, interior morphology, gelation time, compressive modulus, and equilibrium swelling ratio.
In comparison to cocultures, monocultures exhibited higher Young's modulus and equilibrium modulus.
We found that the correlation between modulus (E) and equilibrium swelling (Q) in toluene of the PDMS IPNs obeys a scaling relation identical to that of a normal unimodal PDMS network.
After 21 days, compressive modulus, peak stress, and equilibrium stress demonstrate significant increases of 3.4-fold, 3.3-fold, and 4.0-fold respectively due to in situ mineralization.
Biochemical assays, histological and immunohistochemical analyses, and biomechanical testing were performed to determine biochemical composition, structure, and equilibrium modulus in unconfined compression after 3 weeks of culture.
With increasing porosity, dynamic mechanical analysis (DMA) revealed a decrease in elastic properties such as dynamic stiffness and equilibrium modulus, and an increase of the viscous parameters like damping factor and creep unrecovered strain.
In particular, we assessed the effects of PEG precursor molecular weight (508 Da, 3.4 kDa, 6 kDa, and 10 kDa) and concentration (10 40%) on swelling property, equilibrium confined compressive modulus (HA0), compressive dynamic stiffness, and hydraulic permeability (kp0) of PEG hydrogels in static/dynamic confined compression tests, and equilibrium tensile modulus (Eten) in tension tests.
Collagen menisci matched the alginate control in terms of the equilibrium modulus, and developed a 3- to 6-fold higher tensile modulus than alginate by 4 weeks.
The equilibrium modulus and dynamic stiffness ranged between 0.05 2.5 and 0.16 4.33 MPa, respectively, and were similar to native articular cartilage explants (0.27 and 4.10 MPa, respectively).
Samples were cut to 6 mm in diameter and tested in confined compression to determine equilibrium modulus and hydraulic permeability and analyzed for glycosaminoglycan and hydroxyproline content.
