Current Applied Polymer Science - Volume 6, Issue 1, 2023

The development of new materials is ultimately associated with requirements such as strength, lightness, low production cost, and raw materials from renewable sources, seeking to meet the needs, research, and development of new technologies, which value the qualification of materials from vegetable sources as natural fibers.

In this context, this study aimed to characterize the main physicochemical properties of the natural raffia fiber and its flammability and thermo-acoustic characteristics. These characterizations were performed using several techniques, such as chemical composition analysis, density, moisture adsorption, SEM-EDS, FTIR, and TGA/DTG.

The results showed that the morphology of the raffia fiber presents a similar shape to the beehive. The Elemental analysis of the natural fiber of raffia shows that carbon and oxygen contents are predominant, representing a proportion of more than 90%. Furthermore, the results suggest that the fiber is composed of lignin, hemicellulose, cellulose, tannin, and extractives, with cellulose in a proportion of 80%.

TGA presents a profile similar to large parts of untreated vegetable fibers. The acoustic test showed excellent sound absorption coefficient (α) values at high frequencies, while the flammability test showed that natural raffia fiber is a good flame retardant.

Natural rubber and epoxidized natural rubber composites reinforced with clay have been synthesized in this study using two roll mixing mill.

The aim of the research work was to investigate the influence of clay on the overall performance of NR and ENR based composites.

The effect of clay concentration on basic mechanical properties and molecular transport phenomena of the elastomeric composites was analyzed. Tensile strength and tear strength variation as a function of clay concentration were studied.

It was found that as clay concentration increased up to 4 phr, tensile strength improved up to 22.5 MPa and tear strength up to 32 MPa, beyond which it went down. It was also found that corresponding to 4 phr clay concentrations, the crosslink density of the composite was at a maximum of 1.45 gmol/cc.

As the clay contents are added into the elastomeric matrix system, initially there is a decrease in the swelling coefficient, but later at higher loading, the swelling coefficient increases due to the agglomeration of clay particles in the matrix.

The oral route is the primary route for both acute and chronic treatment of epilepsy. However, lack of oral access during the seizures and high drug resistance limit the anti-epileptogenic effects of most antiepileptic drugs. Therefore, alternative routes and novel drug delivery systems are required. In this study, polymeric microneedles were formulated and characterized for possible intranasal administration of Tiagabine (TIA) in order to overcome the blood-brain barrier (BBB).

In our study, carboxymethyl cellulose (CMC) and Eudragit^® S 100 (ES100) based polymeric microneedles were formulated by micromolding method. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC), X-ray diffractometry (XRD), fourier transform infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance (¹H-NMR), in vitro release, and texture analyses were performed. For the stability analyses, formulations were kept at 25°C ± 2°C (60 ± 5% Relative Humidity; RH), 40°C ± 2°C (75 ± 5% RH) and 5°C ± 3°C for six months.

Analysis results revealed that robust microneedles were formulated successfully by micromolding method with adjustable needle lengths. Depending on the polymer type, sustained TIA releases up to 72 hours were achieved. Structural integrities were maintained at all storage conditions during the storage period of six months.

TIA-loaded microneedles have the potential with less invasive properties, even with small amounts of TIA, through the unconventional nasal route for effective treatment of epilepsy.