Nonwoven Development by the Multilayer Structure

Abstract

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.

Reducing Global Warming Potential Impact of Bio-Based Composites Based of LCA

“…The composite of this composition has an expressed superiority of the lowest impacts on eutrophication and acidification, the other thinner variations of the analogous composites fall three to four times behind in their impacts. In LCA calculation, La Rosa has compared a glass fiber and hemp fiber carpet and the first one has higher impact in all categories, except in occupation of land area [24]. Our study demonstrates the impact of PLA fiber on composites containing plant fibers, which increases the total environmental impact of the composites, but still the impact of these composites on global warming potential is several times lower than from the PA66/GF composite.…”

“…% glass fiber, and in both functional value cases, this composite is used for comparison with hemp/PLA and flax/PLA composites. Data on tensile stress values of hemp/PLA and flax/PLA composites were based on previous studies [23,24].…”

“…For hemp/PLA and flax/PLA, non-woven materials of both compositions, a multilayered or so-called sandwich type structure is created, the production of which is described in previous studies [23,24].…”