Manufacturing and damage analysis of epoxy resin-reinforced scrap rubber composites for aeronautical applications

Simple methods to manufacture elastomer based composites using the styrene-butadiene rubber (SBR) recovered from scrap rubber pieces is proposed. These scraps are obtained basically from the manufacturing of the sport shoes. Epoxy resin is used as reinforcement along with other particles. The effect of combining the reinforcements with recycled SBR is studied by a series of experiments to evaluate the response of these materials to mechanical and thermal loading. Preliminary results on hardness, wear, storage modulus, loss angle tangent, creep response are presented. The results presented are part of an on-going project to design elastomer based composites utilizing recycled SBR for different engineering applications

Manufacturing of new elastomeric composites: Mechanical properties, chemical and physical analysis

Filler-reinforced vulcanized rubber and its blends are frequently used for engineering applications for over a century. Traditional applications include tires, seals, bushings, and engine mounts. The rubbers for tire manufacturing must have high elasticity and frictional properties as well as the high load bearing capacity. Conforming to these needs, rubbers are vulcanized by various materials such as sulphur, carbon black, accelerators, and retardants in different conditions. The reactivity of sulphur vulcanization and physical properties of the final product are affected by the chemical structure, molecular weight, and conformation of the base elastomers. The aim of this study is to investigate the influence of accelerator-vulcanizing agent system and the vulcanization temperature on the mechanical and aging properties of vulcanizates based on Natural rubber/Polybutadiene rubber (NR/BR) compounds. This preliminary study will allow optimizing the composition for improving the mechanical properties and understanding the damage behavior. NR/BR based composites with different vulcanization temperatures and curing systems were characterized. The mechanical properties investigated were tensile strength, elongation at break, tensile modulus at 100 % (M100) and at 300 % (M300) deformation. Hardness (Shore A) and molecular mass of the samples were also determined. Scanning electron microscopy was used to study the microstructure of the fracture surfaces

Synthesis of poly(styrene-co-diene)-block-polyglycidol. Self-association and stabilization of aggregates

A series of amphiphilic poly(styrene(S)-co-diene(D))-b-polyglycidol(G) block copolymers have been synthesized from a parent hydrophobic PS block. The block has been previously functionalized with double bonds of randomly distributed diene units (isoprene (I) or butadiene (B)). Hydrophilic PG blocks of different lengths have been introduced into the above prepolymers. Polymer aggregates of different size and shape have been obtained by dissolving the copolymers in organic and mixed organic/water solutions. The formation of nano-and microsized particles has been revealed by light scattering and microscopic studies. A protocol for preparation of aggregates of a tailored core/shell structure has been demonstrated. Stabilization of particles of the desired morphology with ongoing participation of double bonds in the diene units has been achieved by irradiation with UV light directly in solution

Stabilized amphiphilic poly(styrene-co-diene)-b-poly(ethylene oxide) aggregates

-isoprene (I) or butadiene (B)) prepolymers (bearing hydroxyl or benzyl bromide end groups) and ethylene oxide or mono-methyl poly(ethylene glycol) (PEGs) were used to prepare a series of PS-co-PD-b-PEO amphiphilic copolymers. Investigations on the association and self-assembly of copolymers in dilute organic and in mixed organic/water solutions have been carried out both by light scattering and microscopic measurements. Nanosized and microsized species have been observed. Their shape depends on the hydrophobic/hydrophilic blocks ratio as well as on the solvent composition. Attempts on stabilizing the morphology of the aggregates/micelles have been made by UV-induced cross-linking of diene entities. It has been found that in some experiments, the stabilization proceeds throughout morphological rearrangement determined by the solvent nature and by the cross-linking protocol