The purpose of this study was to produce a novel pH sensitive hydrogel with superior thermal stability, composed of poly(acrylic acid) (PAA) and cellulose nanocrystal (CNC). CNC was extracted from kenaf fiber through a series of alkali and bleaching treatments followed by acid hydrolysis. PAA was then subjected to chemical cross-linking using the crosslinking agent (N,N-methylenebisacrylamide) ...

This report describes a new disintegration tester that can determine not only the disintegration time of orally rapidly disintegrating tablets (ODT), but also the disintegration behavior and mechanism. Using the tester, the disintegration properties of the tablets prepared in a previous study were examined. The purpose of this study is to confirm the utility of the tester as an instrument for e...

A novel pH-responsive superabsorbent hydrogel based on gelatin was prepared through crosslinking copolymerization of poly (acrylic acid) and poly (itaconic acid). The copolymerization conditions including monomers, initiator, gelatin and crosslinker concentration, reaction temperature, and neutralization percent were systematically optimized to achieve a hydrogel with swelling capacity as high ...

Graft copolymers of poly (ethylene glycol) with poly (methacrylic acid) were prepared by reaction of poly (ethylene glycol) methacrylate macromonomer with methacrylic acid in the presence of tetraethylene glycol dimethacrylate as a crosslinking agent. The materials were swollen in aqueous solutions with the pH ranging from 1.5 to 12.0. Dynamic swelling studies were performed. The swelling rates...

Drug release mechamsms of swellable systems for controlled drug administration were investigated The variations of the matrix relaxation and drug diffusion rates were quantified, by measuring the surface area exposed during matrix swelling and drug release as a function of impermeable coating coverage and location. Four different types of matrices, partially coated on various sides, were invest...