Rheological Investigation of Hydroxypropyl Cellulose–Based Filaments for Material Extrusion 3D Printing

Abstract

The rheological properties of drug–polymer mixtures have a significant influence on their processability when using transformative techniques, such as hot-melt-extrusion and material-extrusion 3D printing; however, there has been limited data on printable systems. This study investigated the rheological properties of 17 formulations of successful printed tablets for both immediate and controlled release. Hydroxypropyl cellulose was used in various ratios to obtain printable filaments in combination with various drugs (indomethacin or theophylline), polymers and disintegrants. The complex viscosity, shear thinning behavior and viscoelastic properties were affected by the drug load, polymer composite, disintegrant type, temperature and shear rate applied. Larger windows of processing viscosity were revealed. The viscosity of the printable blends could be as low as the range 10–1000 Pa·s at 100 rad/s angular frequency. All formulations showed shear thinning behavior with a broad slope of complex viscosity from −0.28 to −0.74. The addition of 30–60% drug or disintegrant tended to have greater viscosity values. While microcrystalline cellulose was found to be an alternative additive to lower the storage and loss modulus among disintegrants. This rheological data could be useful for the preformulation and further development of material-extrusion 3D-printing medicines.

Synthesis, Characterization, and Processing of Highly Bioadhesive Polyurethane Urea as a Microfibrous Scaffold Inspired by Mussels

“…As shown in Figure a, PU-LDA, tested at 80, 75, 70, and 65 °C, showed shear thinning behavior at all tested temperatures with values ranging between 10 4 and 10 5 Pa s at a low shear rate (0.01 s –1 ) down to 10 2 Pa s at 100 s –1 , with more than 2 orders of magnitude difference, which agrees with previous studies suggesting that printable polymeric systems are in the range 10–1000 Pa s at high shear rate. , …”

“…Material rheological properties are the most critical parameters for extrusion 3D printing of melted polymers. – Rheology influences the melt temperature and helps determine the material output and flow rate by predicting the material flow and required pressure through the nozzle during the process. In melt extrusion 3D printing, both temperature and shear rate strongly affect the deformation behavior and melt viscosity, which represent the most important parameters in determining the optimal processing conditions.…”

3D-Printing of Silk Nanofibrils Reinforced Alginate for Soft Tissue Engineering

“…Results indicated all samples had potential printability and indicated a dominance of elasticity since the storage modulus was superior to the loss modulus (G′ > G″), especially at higher frequencies. The elastic-dominated trait (G″ < G′) at a low-frequency sweep could result in a rigid construction after printing [ 60 ]. However, the G′ and G″ were the function of the angular frequency (Hz), depending on the sample type.…”

A Sustainable Hydroxypropyl Cellulose-Nanodiamond Composite for Flexible Electronic Applications

“…In fact, in addition to being used in oral pharmaceutical formulations, HPC-based hydrogels were successfully used as scaffolds in tissue engineering [ 15 ]. A recent study proved the suitability of this cellulose derivative for material extrusion 3D printing technique [ 16 ], further widening possible fields of application for such material.…”