Bamboo nanofibers are precious resources that give us the opportunity to implement and strengthen those bio-refined ones that exist today, but are still not competitive enough compared to the production chains that start from oil.
As already introduced in the previous article on the nature of nanofibers and their potential, the materials obtained from bamboo have special mechanical and structural intrinsic characteristics that make them important alternatives to valorize on the market.
But what exactly makes these materials so interesting? What distinguishes them from the other nanofibers being studied? What are the possible applications that would make it possible to make the most of its potential?
In this article we will try to answer these and other questions, creating the theoretical basis from which to develop further insights.
Bamboo is one of the most abundant sources of non-woody cellulose found globally. From a microscopic point of view, bamboo nanofibers have superior mechanical properties compared to nanofibers obtained from woody material and demonstrate different surface properties, such as a more water-repellent trend.
This is mainly due to the high degree of polymerization, the type of hierarchical structure that is created between nanofibrils, that is, how they are organized at a spatial level, but also the size of the nanofibrils. In fact, through microscopic analysis it is possible to observe a dense non-homogeneous network of densely intertwined nanofibrils.
The in-depth knowledge of all these peculiarities in relation to other similar materials is essential to define the most suitable field of application according to the required characteristics.
In addition to the use of bamboo as a structural and architectural material and as a material for the production of objects of design and common use 2, we can identify other categories of products for which scientific research is, to date, very active.
The use of natural nanofibers as reinforcement within composite materials is constantly growing globally due to the multiple advantages they entail, which include their lower weight, the higher surface area, the good mechanical properties and, last but not least, their biodegradability.
Therefore, the use of bamboo nanofibers as fillers for the creation of composites is a field that offers many interesting possibilities. For example, the introduction of bamboo nanofibers into epoxy matrix materials has been shown to improve their physical, mechanical and thermal properties. In particular, these materials can be used in the automotive and aerospace industry as high performance protective coatings or as insulators.
Furthermore, the coupling of these nanofibers with polyvinyl alcohol, a biodegradable synthetic polymer, allows to obtain solid foams (aerogel) with high absorbing capacities, useful for the recovery of organic oils and therefore for environmental preservation treatments. The excellent surface interactions between these two materials, due to the chemical terminal groups present on the surface of the molecules, and the high light transmittance has made them objects of study also for applications in the optical field.
Another possible application is the one which sees the synergic use of chitin, the second most abundant biopolymer on the earth’s surface after cellulose, and bamboo nanofibers. The mechanical properties of the material obtained, and its high biodegradability make it an excellent candidate for use in food packaging applications.
It is interesting, however, to mention also how bamboo is a source of inspiration and not only a primary source of material for productive transformation. In fact, some Chinese and American researchers have taken inspiration from bamboo for its periodic distribution of internal holes along the length of the barrel and the graduated structure of the pores in the cross-section for the design of flexible devices for energy storage.
We have therefore seen how the particular mechanical and chemical properties of cellulose nanofibers obtained from bamboo make them particularly suitable for use as fillers within other materials to increase their performance. In fact, the high mechanical strength and rigidity, due to the high presence of lignin, as well as the abundance of cellulose in the plant and its antibacterial properties, make this material indispensable for applications ranging from biomedical to structural and packaging.
Therefore, the application of bamboo-derived nanofibers even in fields not strictly related to engineering is a growing trend that, however, needs further specific characterization studies to be able to take advantage of the design of all these new products.