3D Printing and HPMC Interfacial Properties

3D Printing and HPMC Interfacial Properties

Hydroxypropyl methylcellulose (HPMC) is an odorless and tasteless white to beige powder.hpmc 200000 It is a non-ionic cellulose mixed ether which is produced by reacting alkali cellulose with methyl chloride and propylene oxide.hpmc 200000 It is used as a binder, coating agent and controlled release matrix in pharmaceutical formulations.hpmc 200000 HPMC is available in various substitution ratios and molecular weights (MW) which influence its properties such as organic solubility, gelation temperature in aqueous solution, swelling, diffusion, and drug release rate.

In tablet manufacturing, HPMC is a widely used binder and coating material.hpmc 200000 It can provide aqueous-soluble films that are easily processed.hpmc 200000 It is also easy to handle and has good tensile strength.hpmc 200000 It can be used to create a tough, durable coating on tablets that will protect them from abrasion. It can also prevent tablet disintegration in the stomach. In addition to its physical and chemical properties, HPMC has the ability to delay hydration of the cement during mixing, thus improving the mechanical strength of the final product.

However, HPMC can be difficult to use as a coating material for 3D printing SAC due to its high viscosity and tendency to bridging or filling the debossed surface of the tablet core.hpmc 200000 To overcome these problems, several low-viscosity grades of HPMC have been developed.hpmc 200000 These low-viscosity grades of HPMC can improve tablet handling and surface wettability, but they may not be as effective in binding the core material to the HPMC coating.

Many researchers have investigated the interfacial properties of HPMC by using various techniques such as viscometry, light scattering, cryo-transmission electron microscopy, ellipsometry, quartz crystal microbalancing with dissipation, and atomic-force microscopy-based imaging [19] and.hpmc 200000 However, these studies only provide a qualitative understanding of the interfacial behavior of HPMC.hpmc 200000 In order to fully understand the underlying mechanism, it is necessary to investigate the interaction between the HPMC and SAC at different temperatures.

In the present study, a SAC-HPMC mixture was sprayed onto the surfaces of three specimens in an experimental apparatus and swelled to form a hard coating by applying an electric field.hpmc 200000 The effect of HPMC on the initial and final set time, compressive strength, shape retainability, and water absorption were measured under four different solutions volume gradients: 0.hpmc 200000 7, 1.1, 1.5, and 1.7 mL/cm2.

The results showed that the addition of HPMC delayed the hydration of SAC by absorbing a large quantity of water.hpmc 200000 The delay effect became stronger when the amount of HPMC increased from 0.hpmc 200000 5% to 1.0%. In addition, the tensile strength of the coated samples was found to increase with the increasing HPMC dosage. The result suggests that the interfacial interaction between SAC and HPMC is temperature-dependent and requires further investigation. The study provides a new understanding of the interfacial behavior of SAC and HPMC and could be helpful in developing high-performance SAC. The adsorption capacity of the SAC was determined to be about 50 g/cm2. In comparison, the adsorption capacity of the HPMC was only 30 g/cm2. This difference is probably due to the different substitution ratios and MW of the two compounds.

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