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The use of the porous Polylactic acid (PLA) for tissue engineering has gained the attention of the researchers worldwide. In this work, PLA tubes were extruded using CO 2 as a foaming agent. The foaming of the PLA tubes at various extruder screw rotational speed and different CO 2 pressure are studied in this work. Subsequently, morphological characterization and surface hydrophilicity studies of the tubes were carried out. It is be found that with an increase in the screw rpm, the contact angle first decreases and reaches the lowest value and then increase with the increase in screw rpm. Similarly, the effects of screw rpm and gas pressure on cross-sectional morphology and FTIR spectra were observed indicating an increase in crystallinity. [ABSTRACT FROM AUTHOR]

Magnesium and its alloys are getting more attention in the field of tissue engineering as it is biodegradable as well as biocompatible. An open cell structure in particular offers the advantage of body fluid transportation through it and allows the growth of new tissues. Open cell Mg foams with pore interconnectivity are difficult to fabricate from conventional techniques. In the present work, a novel approach has been successfully developed to fabricate the open cell Mg structures with pore interconnectivity using powder metallurgy route and Ti-woven wire mesh as a space holding material. Pore morphology and percentage porosity can be easily altered by adjusting the Ti-wire diameter and shape of construct. Ti-woven wire mesh in the shape of netted wire gave the best result in terms of homogeneity of pores and strength. Maximum porosity achieved is 60% and ultimate tensile strength is measured to be 78 MPa for the porous structure. [ABSTRACT FROM AUTHOR]

Highlights • A novel single step biaxial expansion method is used for bioresorbable tube fabrication. • Biaxially expanded tubes have better radial compressive properties. • Brittle behaviour of PLA changes to ductile by addition of 5 wt% PCL. Abstract Bioresorbable stents is going to become the future modality for the treatment of coronary artery disease (CAD). However, the main limitation of the polymeric stent is its poor mechanical properties. For the proper functioning of a stent in the artery; it is required to enhance the radial stiffness of the polymeric stent. Polymeric tube manufacturing is the first and most important step in the stent manufacturing process. Usually, post processing operation which enhances the mechanical properties such as annealing, blowing and die drawing near glass transition are used after tube extrusion. In this study, along with conventional tube extrusion process (SE), a single step biaxial expansion method (BAE) was employed during the tube extrusion. The effect of manufacturing method on the radial compressive strength of the extruded tubes is thereby evaluated. For further determining the tubes radial resistive force, parallel plate crush testing as per ISO 25539-2 was performed and it is observed that tubes extruded by BAE method have better performance during crush testing as compared to the SE tubes of the same material. SEM was used for observing the cross-sectional morphology of the Cryo-fractured surface of fabricated bioresorbable tubes. [ABSTRACT FROM AUTHOR]

Abstract: In this research article, novel porous microcellular ABS foams were fabricated and subsequently investigated for their morphological attributes. Initial research focuses on developing ultra-low density closed cell foams through cyclic microcellular foaming process. First stage foaming process develops microcells which affect the second stage of the batch foaming process. Hence, the effect of repeated foaming process on foam density and its morphology are discussed. Subsequently, ultrasound excitations were utilized to rupture the closed cell walls, thereby developing porous structure. The combined cyclic solid-state foaming and ultrasound excitation provides a way to fabricate ultra-low density porous polymers. [Copyright &y& Elsevier]