Mechanical, Thermal and Ballistic Performance of Epoxy Composites Reinforced with Cannabis sativa Hemp Fabric

AbstractThis work investigated the impact that the processing of hemp (C. sativa L.) fibre has on the mechanical properties of unidirectional fibre-reinforced epoxy resin composites loaded in axial tension, and particleboard reinforced with aligned fibre bundles applied to one surface of the panel. For this purpose, mechanically processed (decorticated) and un-processed hemp fibre bundles, obtained from retted and un-retted hemp stems, were utilised. The results clearly show the impact of fibre reinforcement in both materials. Epoxy composites reinforced with processed hemp exhibited 3.3 times greater tensile strength when compared to the un-reinforced polymer, while for the particleboards, the bending strength obtained in those reinforced with processed hemp was 1.7 times greater than the un-reinforced particleboards. Moreover, whether the fibre bundles were processed or un-processed also affected the mechanical performance, especially in the epoxy composites. For example, the un-processed fibre-reinforced epoxy composites exhibited 49% greater work of fracture than the composites reinforced with processed hemp. In the wood-based particleboards, however, the difference was not significant. Additionally, observations of the fracture zone of the specimens showed different failure characteristics depending on whether the composites were reinforced with processed or un-processed hemp. Both epoxy composites and wood-based particleboards reinforced with un-processed hemp exhibited fibre reinforcement apparently able to retain structural integrity after the composite’s failure. On the other hand, when processed hemp was used as reinforcement, fibre bundles showed a clear cut across the specimen, with the fibre-reinforcement mainly failing at the composite's fracture zone.

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Tucum Fiber from Amazon Astrocaryum vulgare Palm Tree: Novel Reinforcement for Polymer Composites

Polymers ◽

10.3390/polym12102259 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2259

Author(s):

Michelle Souza Oliveira ◽

Fernanda Santos da Luz ◽

Andressa Teixeira Souza ◽

Luana Cristyne da Cruz Demosthenes ◽

Artur Camposo Pereira ◽

...

Keyword(s):

Polymer Composites ◽

Impact Energy ◽

Natural Fibers ◽

Critical Length ◽

Epoxy Composites ◽

Synthetic Fiber ◽

Palm Tree ◽

Ballistic Performance ◽

Synthetic Fibers ◽

Izod Impact

The replacement of synthetic fibers by natural fibers has, in recent decades, been the subject of intense research, particularly as reinforcement of composites. In this work, the lesser known tucum fiber, extracted from the leaves of the Amazon Astrocaryum vulgare palm tree, is investigated as a possible novel reinforcement of epoxy composites. The tucum fiber was characterized by pullout test for interfacial adhesion with epoxy matrix. The fiber presented a critical length of 6.30 mm, with interfacial shear strength of 2.73 MPa. Composites prepared with different volume fractions of 20 and 40% tucum fiber were characterized by tensile and Izod impact tests, as well as by ballistic impact energy absorption using .22 ammunition. A cost analysis compared the tucum fiber epoxy composites with other natural and synthetic fiber reinforced epoxy composites. The results showed that 40 vol% tucum fiber epoxy composites increased the tensile strength by 104% and the absorbed Izod impact energy by 157% in comparison to the plain epoxy, while the ballistic performance of the 20 vol% tucum fiber composites increased 150%. These results confirmed for the first time a reinforcement effect of the tucum fiber to polymer composites. Moreover, these composites exhibit superior cost effectiveness, taking into account a comparison made with others epoxy polymer composites.

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Hemp fabric/epoxy composites manufactured by infusion process: Improvement of fire properties promoted by ammonium polyphosphate

Composites Part B Engineering ◽

10.1016/j.compositesb.2015.10.045 ◽

2016 ◽

Vol 89 ◽

pp. 117-126 ◽

Cited By ~ 37

Author(s):

Luca Boccarusso ◽

Luigi Carrino ◽

Massimo Durante ◽

Antonio Formisano ◽

Antonio Langella ◽

...

Keyword(s):

Process Improvement ◽

Ammonium Polyphosphate ◽

Epoxy Composites ◽

Fire Properties ◽

Hemp Fabric

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Effect of graphene nanoplatelets on the ballistic performance of hybrid Kevlar/Cocos nucifera sheath-reinforced epoxy composites

Textile Research Journal ◽

10.1177/0040517519833970 ◽

2019 ◽

Vol 89 (21-22) ◽

pp. 4349-4362 ◽

Cited By ~ 5

Author(s):

J Naveen ◽

M Jawaid ◽

ES Zainudin ◽

Mohamed TH Sultan ◽

R Yahaya

Keyword(s):

Energy Absorption ◽

Laminated Composites ◽

Cocos Nucifera ◽

Graphene Nanoplatelets ◽

Epoxy Composites ◽

Ballistic Limit ◽

Ballistic Performance ◽

Gas Gun ◽

Significant Difference ◽

Ballistic Properties

This study investigated the effect of graphene nanoplatelets (GnPs) on the ballistic performance of Kevlar/ Cocos nucifera sheath-reinforced epoxy composites. GnPs with different wt. % (0%, 0.25%, 0.50%) were integrated into epoxy resin through ultra-sonication. Laminated composites were fabricated by incorporating Kevlar and Cocos nucifera sheath layers into the epoxy/GnP mixture by the hand lay-up method followed by hot pressing. Nine- and 12-layered laminates were fabricated with different numbers of Kevlar and Cocos nucifera sheath plies. Ballistic tests were conducted using a single-stage gas gun experimental setup with an 8 mm hemispherical stainless steel projectile. The results showed that the addition of GnPs improved the energy absorption by 8.5% (nine plies) and 12.88% (12 plies) and the ballistic limit by 4.28% (nine plies) and 6.17% (12 plies), respectively of Kevlar/epoxy/GnP composites at 0.25 wt. %. However, hybrid Kevlar/ Cocos nucifera sheath/epoxy/GnP composites and Cocos nucifera sheath/epoxy/GnP laminated composites decreased the energy absorption and ballistic limit after the addition of GnPs. This is because the addition of GnPs improved the interfacial interactions between the fiber and GnP modified epoxy matrix, which is inappropriate to absorb and dissipate the kinetic energy of the projectile. Statistical analysis was carried out using one-way analysis of variance and it was shown that there is a statistically significant difference between the obtained ballistic properties of the laminates.

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Ballistic Performance of Guaruman Fiber Composites in Multilayered Armor System and as Single Target

Polymers ◽

10.3390/polym13081203 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1203

Author(s):

Raphael Henrique Morais Reis ◽

Larissa Fernandes Nunes ◽

Fernanda Santos da Luz ◽

Verônica Scarpini Candido ◽

Alisson Clay Rios da Silva ◽

...

Keyword(s):

Structural Integrity ◽

Natural Fiber ◽

Fiber Composite ◽

Epoxy Composites ◽

Ballistic Performance ◽

Single Target ◽

The Us ◽

Lethal Limit ◽

First Time ◽

Armor System

Multilayered armor systems (MAS) with a front ceramic layer backed by a relatively unknown Amazonian guaruman fiber-reinforced (Ischnosiphon koem) epoxy composites, as second layer, were for the first time ballistic tested against the threat of 7.62 mm rifle ammunition. The amount of 30 vol% guaruman fibers was investigated in three distinct configurations: (i) continuous aligned, (ii) 0–90° cross-laid, and (iii) short-cut randomly dispersed. Additionally, single-target ballistic tests were also carried out in the best MAS-performed composite with cross-laid guaruman fibers against .22 caliber ammunition. The results disclosed that all composites as MAS second layer attended the US NIJ standard with corresponding penetration depth of (i) 32.9, (ii) 27.5, and (iii) 29.6 mm smaller than the lethal limit of 44 mm in a clay witness simulating a personal body. However, the continuous aligned guaruman fiber composite lost structural integrity by delamination after the 7.62 projectile impact. By contrast, the composite with cross-laid guaruman fibers kept its integrity for subsequent shootings as recommended by the standard. The single-target tests indicated a relatively higher limit velocity for .22 caliber projectile perforation, 255 m/s, and absorbed energy of 106 J for the cross-laid guaruman fibers, which are superior to corresponding results for other less known natural fiber epoxy composites.

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