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Polymer composites based on biodegradable polylactide/poly[(butylene succinate)‐co‐adipate] (PLA/PBSA) blend and pristine and organically modified clays have been prepared via melt‐mixing in a batch‐mixer. Four different surfactants have been used to modify the pristine montmorillonite (MMT) clay. The weight ratio of the PLA and PBSA is 70:30, while the weight of the MMT is fixed at 6%. The surface morphologies of the unmodified and organoclay‐modified blends have been studied by field‐emission scanning electron microscopy. Results show that the domain size of the dispersed PBSA‐phase is reduced with the addition of organoclay and the extent of this reduction in the size of PBSA domain is dependent on not only the interlayer spacing of the clay but also enthalpic interaction between the clay surface and the polymer blend. The degree of dispersion of silicate layers in the blend matrix has been characterised by X‐ray diffraction. The improved adhesion between the phases and the fine morphology of the dispersed phase contributes to the improvement in the mechanical and thermal properties of the final polymer blend–organoclay composites over PLA/PBSA blend. On the basis of these results, we propose a general understanding on how the morphology of the blends is related to the final properties. magnified image

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Current centralised healthcare models pose many challenges, particularly for developing countries such as South Africa, where travel and time costs make it difficult for patients to seek healthcare, even when urgently needed. To address this issue, point-of-care (PoC) tests, which are performed at or near the site of clinical care, have gained popularity and are actively being developed. Microfluidic systems, in which small volumes of fluids can be processed, provide an ideal platform on which to develop PoC diagnostic solutions. Specifically, the emerging field of paper-based microfluidics, with advantages such as low-cost, disposability and minimal external equipment requirements, provides unique opportunities for addressing healthcare issues in developing countries. This work explores the field of paper-based microfluidics, with step-by-step instructions on the design, manufacture and testing processes to realise paper-based devices towards diagnostic applications. Paper-based microfluidic and electronic components are presented, as well as the integration of these components to provide smart paper-based devices. This serves as an educational tool, enabling both beginners and experts in the field to fast-track development of unique paper-based solutions towards PoC diagnostics, with emphasis on the South African context, where both the need for and impact of these solutions are great.