The present investigation pertains to the existent possibilities of the fibrous natural material Luffa Cylindrica (LC) as reinforcement to thermoset resins. The main purpose was the manufacturing of an engineering material that would, simultaneously, lead to a more sustainable world. In an effort to optimize the final mechanical properties, semi‐ green Epoxy Resin/Luffa Cylindrica (ER/LC) composites were manufactured, applying a number of different manufacturing parameters combinations. The manufacturing parameters taken into account were: (a) fiber chemical treatments; (b) the external applied pressure during curing; (c) number of plies; (d) stacking sequence effect; (e) LC's structural characteristics; and (f) the influence of fiber weight fraction on composite's behavior. The elastic flexural response of the composite polymer was found improved with respect to neat polymer's response due to fibers' nature and the applied manufacturing optimization process. This improvement was reflected to material's stiffness which optimally increased by 48% for a mechanically applied pressure of 4.6 kPa during curing. Additionally, LC fibers chemically treated with Acetone/ CH3COOH 1 wt % led to stiffness' improvement up to 30%. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41992.

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This study outlines a method for the epoxidation of poly-beta-myrcene, a biopolymer that can be easily extracted from the natural resin of the Chios Mastic tree (Pistacia lentiscus L.). The resulting epoxidation products are self-curing, and have a nearly 100% green carbon content. These Mastic Epoxide products (MASTEP) have the potential to be useful thermosetting resins. One specific product (MASTEP A), was used as an adhesive to create Single Lap Joints, which were then subjected to tensile shear stress tests. MASTEP A was found to be 25%-83% stronger than three commonly used conventional or "semigreen" epoxy adhesives. Another specific product (MASTEP B), was found able to be thermally converted into a semi-crystalline form. In order to clarify the 3D chemical structure of MASTEP, IR, and DSC investigations were conducted. The entire production process was designed to be environmentally friendly. The results of this research represent a significant advancement in the development of environmentally friendly epoxies and pave the way to a wide range of potential further research.

Natural fiber (NF)‐reinforced thermosetting composites exhibit excellent properties but, due to the usually hygroscopic nature of the fibers, these composites may suffer from the effects of moisture absorption. Luffa cylindrica is a NF, potentially useful in the manufacture of composite materials, but it is highly hygroscopic. A technology is developed for the fabrication of moisture‐resistant L. cylindrica‐reinforced epoxy composites and the various parameters that affect the process are investigated using long‐term moisture absorption experiments and dynamic mechanical analysis of dry and moist specimens. The technology concludes to a L. cylindrica‐reinforced bilayer matrix made of a first linseed oil‐modified precured epoxy and a final unmodified epoxy layer. This composite offers a reduced water absorbance by 33% and an almost identical Tg compared to the non‐modified epoxy reinforced with L. cylindrica. The same technology is used to manufacture water‐resistant L. cylindrica‐reinforced composites from both, environmentally friendly, matrix and reinforcement.

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