The influence of defects on the mechanical properties of short fibre reinforced thermoplastics

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The Influence of Plasticizer Content and Type on the Rheological Behaviour of Plastisol Used in Coated Fabrics

Coating pastes need to have very specific rheological properties because of the methods in which they are applied. Composition of the paste can be formulated in such a manner to achieve the desired rheological behaviour. In this research work rheological measurements of paste with nine various plasticizer content using DOP and DOA, and PVC-E with three k-values (69, 70, 75) were studied. The results indicate that pastes are characterized by a non-Newtonian pseudoplastic flow under the studied conditions. The power-law index ( n) values of the pastes show that the flow properties of pastes change to Newtonian flow above 50 phr plasticizer content. It was also found that the consistency index (k) of the pastes were decreased with increasing plasticizer content. Statistical analysis carried out show very good correlation between the studied parameters. </jats:p

A review on new mesostructured composite materials: Part I. synthesis of polymer-mesoporous silica nanocomposite

Mesoporous silicas are inorganic materials with large surface areas, uniform framework structures and readily controlled pore diameters which are synthesized in the presence of surfactants as structure-directing agents, followed by the removal of the surfactant by extraction or calcination. Due to their characteristics, such as ordered structure, high surface area, and favorable interfacial interactions between silica surface and the polymer, they have found excellent potential application for use as reinforcing agents for several engineering polymer systems. While a large number of different synthesis approaches for the preparation of mesoporous silica-polymer nanocomposites has been reported in literature, there is nevertheless a growing need for verified synthesis methods of mesoporous silica-polymer materials. This paper presents a review of the literature on the methods for synthesizing polymer-mesoporous silica nanocomposites and discusses some unique properties of these composites. </jats:p

A review on new mesostructured composite materials: Part II. Characterization and properties of polymer–mesoporous silica nanocomposite

Hybrid inorganic–organic materials are promising systems for a variety of applications due to their extraordinary properties with intricate composite architectures composed of nanoscale inorganic moieties with organic polymers synergistically intertwined to provide both useful functionality and mechanical integrity. These materials have a high potential for future applications and therefore attract considerable interest in polymer science research during the last years. Among the various explored inorganic nanostructures, the mesoporous silica has been considered as a fascinating material to construct novel ordered and well-dispersed nanocomposites due to their high surface areas, periodic and size-controllable pore channels. This review is written with the intention to give an overview of the characterization and material properties of polymer–mesoporous silica nanocomposites. Among polymer–mesoporous silica composites, various categories including polyaniline, polypyrrole, polystyrene, polypropylene, polyethylene, epoxy, rubber, and acrylate polymer were discussed in detail.</jats:p

Oxidant/antioxidant status in Type-2 diabetes mellitus patients with metabolic syndrome

Background: The concurrence of metabolic syndrome (MS) and diabetes mellitus (DM) is increasing worldwide. The long-term complications of these chronic diseases are a threat to patients' well-being. Oxidative stress is involved in the pathogenesis of several diseases. To understand the basic pathophysiological mechanisms of Type-2 DM (T2DM) and its related complications, we aimed to investigate the oxidant/antioxidant status and Na+-K+ ATPase activity in T2DM with MS. Materials and Methods: A population of ninety individuals including fifty patients diagnosed with T2DM and MS, but without overt diabetes complications, and forty individuals without T2DM or MS as control group participated in this study. Plasma malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) activities, total antioxidant capacity (TAC), and Na+-K+ ATPase activity were assessed by standard laboratory methods. Results: Plasma MDA in patients group was statistically significantly higher than that of controls (P 0.05). Results from the patient group showed positive correlations between CAT activity and triglyceride and positive correlations between GPx activity and weight, body mass index (BMI), and waist circumference. In addition, there was a positive correlation between MDA results with high-density lipoprotein-cholesterol (HDL-C) and total cholesterol and a negative correlation with TAC, BMI, and weight (P <= 0.05) in controls. Conclusion: Because T2DM patients were without any vascular complications, antioxidant defense results may reflect the lack of progression of diabetes complications in these patients. These results emphasize the need for initial and continued assessment of cardiovascular disease risks in diabetic individuals. Implementation of timely interventions may improve the management of diabetes and prevent the progression of diabetes complications