The view towards a sustainable bioeconomy is increasing the interest of using renewable natural resources in the production of composites. Until now, the production of sustainable composites has been mainly examined from the point of view of material composition and structure, by replacing petroleum-based components with those that are obtained from renewable resources known as natural fiber composites (NFCs). The usefulness of newly acquired materials is mostly evaluated considering their performance and economic costs, whereas the aspect of environmental protection is underestimated. The impact of composites that are made from renewable resources is examined within the two parts of this study—the first part compares different nitrogen (N) fertilization scenarios for plant origin (hemp and flax) fibers. When compared, hemp crops show higher CO2 accumulation, (−1.57 kg CO2 eq) than flax (−1.27 kg CO2 eq). In addition, the environmental impact of both fiber types is compared to polyamide composites, one of the traditionally used materials in the automotive industry in the second part of this study. According to the conducted life cycle assessment, Flax/PLA emits 1.19 kg CO2 eq per 1 kg composite, Hemp/PLA 1.7 kg CO2 eq per 1 kg composite, and PA66/GF 9.14 kg CO2 eq per 1 kg composite. After the comparison, it was concluded that bio-based composites are able to ensure lower CO2 emissions, because CO2 is accumulated and stored in the fibers, however the traditionally used composites are able to provide a lower impact in other environmental categories.
The main two directives of the European Commission (EC) has been regulating the automotive industry. The aforementioned directives and education of residents on environmental issues has created the need for new materials that have been produced from renewable resources and should be recycled at the end of product life cycle. The objective of this project is to develop a nonwoven materials (NWM) that would incorporate fibers of plants, which could be grown in Latvia because of suitable local climate conditions, for the use in automotive industry. Furthermore, inclusion of polymer fibers in the NWM will expand the areas of use of such material – the NWM can be transformed into a composite material by means of a thermal press. Manufacturing process of NWM consist of structure modelling and material samples manufacturing. NWM samples production process to be carried out by fibers preparation, fibers mixing, formation by airlaid method, preparation of fiber webs for fixation with a mechanical needle punching method, mechanical fixation of fiber webs, preparation of fixed fiber webs for NWM manufacturing and manufacturing of NWM by mechanical needle punching method. This article reflects the comparison of two compositions NMW (Polylactid (PLA) (60 wt%) and long flax fibres (40 wt%), and PLA (60 wt%) and technical hemp fibres (40 wt%)) with the same structure by visual appearance, geometrical parameters and tensile strength. The average surface density of hemp NWM varies in the range of 792.09 to 958,71 g•m−2 , thickness varies from 6.91 to 9.23 mm. Flax NWM average surface density is higher than hemp NWM and varies in range of 1,064 to 1,260 g•m−2, thickness of the material varies from 12.62 to 15.54 mm. For comparison, the surface density of NWM currently used in automotive industry, depending on the use of the material, varies from 100 to 1,400 g•m−2.
-Hemp cultivation is one of the possibilities to use agricultural land of Latvia. Mechanical and physical properties of hemp fiber and its chemical structure is suitable for using as a reinforcement, but polypropilene (PP) fibers and PolyLactic Acid (PLA) fibers as a matrix for bio-composites. Compression molding is the most common composite processing technology. Composites with the content of 20 % -40% of natural fiber could provide optimal mechanical properties. The demand for bio-composites with improved properties will be increasing in the future. Sandwich structure of bio-composite is one of the ways to protect natural fiber from heating degradation.
Textile applications have a significant role in the automotive architecture. The structure of textiles, used fibres and textile producing technology depends on textile placement in the car. Sound absorption is a very important property of textiles because of the large number of noise sources in a car (engine and driving noise) and from the road. Nonwoven fabrics have the ability to reduce noise; other significant benefits of nonwovens are high productivity, low production costs, opportunity to blend natural fibres into them and possibility to use nonwovens as base component of composites.
Dizaina tehnoloģiju institūts, Materiālzinātnes un lietišķās ķīmijas fakultāte, Rīgas Tehniskā universitāte Kopsavilkums. Pētījumā aplūkotajiem kaņepju (60 masas %) un polilaktīda (PLA) (40 masas %) neausto materiālu (NM) paraugiem izstrādāta t.s. sendvičtipa struktūra, kur ārmalas izgatavotas tikai no PLA šķiedru klājuma kārtām, bet vidus daļā šķiedru klājuma kārtas veido PLA šķiedru atlikums, kas vienmērīgi sajaukts ar kaņepju šķiedrām. NM paraugu izgatavošanas mērķis ir to tālāka pārveide biokompozīta materiālā.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.