Fracture toughness is generally considered as the main properties of a polymer or a polymer adhesive system for measuring the material resistance to the extension of cracks. Epoxy adhesives are generally brittle in nature; however, the addition of a second dispersed phase could induce a remarkable increase of damage tolerance performance by an enhancement of the material fracture toughness. The fracture behavior of a filled epoxy resin is strongly affected by the dimensions, the shape, and the chemical nature of the considered filler. The chapter describes the different toughening mechanisms for polymer adhesives with special attention toward innovative nanofiller such as graphene nanoplatelets and hyperbranched polymer nanoparticles.

The aimof this studywas to assess the phytotoxic potential of Cleome arabica L, as well as to isolate the main bioactive\ud compounds. Phytotoxicity was evaluated on germination and seedling growth of Lactuca sativa, Raphanus\ud sativus, Peganum harmala and Silybum marianum, through testing aqueous and organic extracts of different C.\ud arabica organs (roots, shoots, siliquae and seeds). Results showed that siliquae methanol extract caused the\ud greatest negative effect on lettuce germination and growth. For the bioactive subfractions (petroleum ether,\ud ethyl acetate andmethanol–water), the ethyl acetate induced highly significant reduction, showing 100% inhibition\ud of lettuce growth at 6 g/L. The bioactive ethyl acetate subfraction was chromatographed and subjected to\ud NMR techniques. Based on bio-guided chromatographic fractionation, five bioactive allelochemical compounds\ud were isolated from ethyl acetate extract of siliquae of C. arabica. The most inhibitory compound on lettuce seedling\ud growth was elucidated as 11-α-acetylbrachy-carpone-22(23)-ene

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Through recent discoveries and new knowledge among correlations between molecular biology and materials science, it is a growing interest to design new biomaterials able to interact-i.e., to influence, to guide or to detect-with cells and their surrounding microenvironments, in order to better control biological phenomena. In this context, electro-active polymers (EAPs) are showing great promise as biomaterials acting as an interface between electronics and biology. This is ascribable to the highly tunability of chemical/physical properties which confer them different conductive properties for various applicative uses (i.e., molecular targeting, biosensors, biocompatible scaffolds). This review article is divided into three parts: the first one is an overview on EAPs to introduce basic conductivity mechanisms and their classification. The second one is focused on the description of most common processes used to manipulate EAPs in the form of two-dimensional (2D) and three-dimensional (3D) materials. The last part addresses their use in current applications in different biomedical research areas including tissue engineering, biosensors and molecular delivery.