Page 43 - New Cloth Market December 2022 Digital Edition

Industrial Hemp Fibers: An Overview

tomotive, composites, fiberboard, heat- to 30% stronger for the same weight Advanced research and progress have
insulating materials [25,42], and build- and exhibit a non-brittle fracture on gone into increasing hemp fibers’ me-
ing construction, for example, in fiber- impact, which is an important require- chanical performance through surface
reinforced concrete [19,25,92]. Tran et ment for interior automotive plastic treatments in order to improve their
al. [93] showed that hemp concrete can components [97]. wettability and dimensional stability as
decrease daily indoor relative humidi- well as increase the interfacial bond-
ty variations and reduce energy con- An increasing number of car models ing between matrix and fibers. The most
sumption by 45% as compared to cel- are using natural fiber-reinforced poly- promising application for hemp fibers
lular concrete. Recent studies have meric composites in door panels, in- is as reinforcement in polymeric com-
shown that hemp fibers can also be struments panels, engine covers, sun posites or through hybridization. Hybrid-
employed for sound insulation and/or visors, and air filters, and the number ization allows the possibility of over-
sound absorption [94]. of applications are expanding to more coming the limitations and provides
structural components such as seat new opportunities to broaden the ap-
New research for hemp fiber applica-
backs and exterior underfloor paneling plicability of hemp fibers in high-end
tions are in sporting goods or musical
[20,46]. applications. It is worth mentioning that
instruments due to their higher vibra-
hemp fiber hybrid composites bring a
tion-damping capacity than that of syn- Conclusions competitive market to various indus-
thetic fibers [43] as well as reinforce-
trial applications.
ments in brake pad applications. The Industrial hemp (Cannabis sativa) has
modified formula for brake pads con- been extensively researched over re- Industrial hemp is being used in a num-
tains natural hemp fibers and a cent years for the development of new ber of industries such as textiles, au-
geopolymer as a fraction replacement materials and is getting more attention tomotive, composites, fiberboard, heat-
for synthetic Kevlar fibers and phenol- as a possible alternative replacement insulating materials, in fiber-reinforced
ic resin, respectively [95]. The auto- for synthetic fibers. Interest is warranted concrete, sound insulation and/or
mobile industry is constantly search- due to its low density, high specific sound absorption as well as in sport-
ing for eco-friendly materials to use in strength and stiffness, as well as the ing goods or musical instruments or
its products; therefore, the most re- fact that hemp fibers have a relatively as reinforcements in brake pad appli-
searched and expanding application for low cost, are from renewable resourc- cations. However, more research is
hemp fibers and natural fibers, in gen- es, and the wastes are 100% biode- needed to expand their application
eral, is as reinforcement in polymeric gradable. However, the major disadvan- range and improve their properties. The
composites in automotive applications, tages of hemp fibers are their inherit- biodegradability issue is one problem
such as those described in Table 5 ed hydrophilic character, low resis- that must be explored when research-
[27,29,96]. Composites reinforced with tance to microorganisms, low thermal ing hemp fiber composite applications
natural fibers such as hemp can be an stability, and variability in their proper- and considering long life-cycle appli-
alternative to glass fiber-reinforced ties because they depend on growth cations along with the reproducibility
composites, because they can be 25% conditions and maturity. of these composites’ final properties.

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