When laying up dry composite materials and aligning the fibers in the appropriate directions it can be a challenge due to the dryness of the fiber and mold design. Several commercial products are available to help fix plies to molds keeping the proper fiber orientation depending upon mold geometry. Prepreg and wet layups do not have this problem due to the inherent inclusion of a matrix in their manufacturing, dry materials have no added epoxy at the time of layup and are therefore in need of assistance maintain position. The purpose of this research is to determine if Super 77™ or EPON™ 2002 increases or decreases mechanical properties of the neat resin and composite laminates; if the increase or decrease is dependent upon the type of epoxy, and if the amount of applied tackifier can be optimized towards a high or low application quantity to minimize any detrimental effects to mechanical properties. Each tackification agent was applied in high and low concentrations to eight composite panels, with two control panels. The EPON™ was applied manually and set with heat exposure while the Super 77™ was sprayed from an aerosol can. The Super 77™ plies were stacked and pressed by hand while the EPON™ plies were stacked and ironed together to create panels, which were then infused with one of two room temperature infusion epoxies, MVS 610 or INF 114. The panels were then cut to specimen size for testing. Neat resin specimens were cast in silicone molds with high and low concentrations of tackifiers and allowed to cure for 12 hours at room temp, then heated to 60° C for 8 Both Super 77™ and EPON™ 2002 reduced the SBS for both epoxies, but Super 77™ reduced the short beam shear more than EPON™ 2002. The modulus of the neat resin cast specimens with high concentration were between 0 to 20% lower than neat resin with no tackifier; the tensile strength was increased for those specimens with Super 77™ and lower for those with EPON™ 2002. Similarly, the Charpy test resulted in higher values for Super 77™ than for EPON™ 2002. The effects of Super 77™ and EPON™ 2002 are complex and varied depending on application concentration, resin, and tackifier type; but the addition of any tackifier reduces mechanical properties from non-tackified laminates.

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In recent decades, the necessity to find a completely environmentally friendly substitute for synthetic fibres in composite applications has intensified, driven by the objective of reducing emissions in both the production and disposal of composite components. Natural fibres present a potential solution, yet they have some issues such as the inhomogeneous quality of their cross-section and mechanical properties, depending on different aspects, for example, growing conditions and the amount of intake water. Another potential solution is organic man-made fibres, such as fibre made from Cellulose NanoFibrils, which do not present the previously cited drawbacks.This thesis investigates and compares the potentials of organic fibres, either man-made or natural, in composite reinforcement applications. To accomplish this, organic fibres are integrated into composite plates using two distinct thermoset matrices, epoxy and vinyl ester, respectively via methods of hot pressing and vacuum infusion. Subsequently, the produced composite plates undergo tensile testing, with the results being compared with the theoretical values. Furthermore, microscopy is employed to examine the adhesion at the interface between reinforcement and matrix.The findings indicate that man-made fibres from Cellulose NanoFibrils bind more efficiently with thermoset matrices compared to flax fibres, making them more adept as reinforcement materials for thermoset composites. / Under de senaste decennierna har behovet av att hitta en helt miljövänlig ersättning för syntetiska fibrer i kompositapplikationer intensifierats, drivet av målet att minska utsläppen både vid produktion och avfallshantering av kompositkomponenter. Naturliga fibrer presenterar en potentiell lösning, men de har vissa problem som den ojämna kvaliteten på deras tvärsnitt och mekaniska egenskaper, beroende på olika aspekter, till exempel växtförhållanden och mängden intaget vatten. En annan potentiell lösning är organiska konstgjorda fibrer, som fibrer tillverkade av cellulosa nanofibriller, som inte har de tidigare nämnda nackdelarna.Denna avhandling undersöker och jämför potentialen hos organiska fibrer, antingen konstgjorda eller naturliga, i kompositförstärkningsapplikationer. För att uppnå detta integreras organiska fibrer i kompositplattor med hjälp av två olika termohärdande matriser, epoxi och vinyl-ester, via metoder för varmpressning och vakuuminfusion. Därefter genomgår de producerade kompositplattorna dragprovning, med resultaten jämförda med de teoretiska värdena. Dessutom används mikroskopi för att undersöka vidhäftningen vid gränssnittet mellan förstärkning och matris.Resultaten indikerar att konstgjorda fibrer från cellulosa nanofibriller binder effektivare med termohärdande matriser jämfört med linfibrer, vilket gör dem mer lämpliga som förstärkningsmaterial för termohärdande kompositer.