NIST develops composites made from wood pulp and marine life

Recently, a team of the National Institute of Standards and Technology (NIST) developed a new composite of wood and invasive marine invertebrates that can improve materials in food packaging, biomedical equipment, construction and transportation design. And other applications. The study, published in the journal Advanced Functional Materials, combines wood pulp derivatives with dried tunicate biota to create new, flexible, sustainable, non-toxic, and UV-reflective properties. Composite material.

The project was originally inspired by super tough natural composites containing Buligand structures, which are common in naturally designed materials. In such a structure, since any impact force is pushed by the nano-scale to a series of meandering curves, the molecules are layered in the rotating microstructure, which is elastic to the crack, thereby causing the energy to be deflected, thereby maintaining the entire material. Structure and function.

Jeff Gilman said: "If you develop the right product, it can be used in everything from aerospace composites to fresh food packaging."

Although wood does not have a natural Brigigand structure, by washing the wood pulp with an acid to remove lignin and amorphous cellulose, a dry emulsion solution can be produced to form a new material having the structure. For their part, these Buligand films are quite fragile and difficult to withstand large weights. However, when a short wood-derived nanocellulose rod is combined with another natural material with a longer rod, the resulting new material is both strong and soft.

To this end, the researchers used dry tunicates because they consist of extremely long and highly crystalline nanocellulose, which is quite different from the shorter crystals in wood. A large number of tunicates are often found on docks and docks in warm waters, and they are one of the Asian dishes. The tunicates used here are captured in western France, where they are considered pests.

By testing the composite, the exact point of maximum toughness can be determined. The addition of these tunicates means that the nanocrystals are distorted in different ways and increase the structure of the wood pulp, resulting in a tighter and denser structure that makes the material UV reflective. As NIST Composites project leader Jeff Gilman points out: “Many materials begin to degrade if exposed to sunlight for extended periods of time, so this material may be used as a coating on other surfaces to reflect light and extend material durability. ."

The team will continue to explore new blending methods to make industrial composites. As Jeff Gilman said: “If you develop the right product, it can be used in everything from aerospace composites to fresh food packaging.”