Fuji Pigment Establishes Manufacturing Process for CNF Composite Material

Cellulose nanofiber (CNF), considered a next-generation material, is made of wood-based biomass from trees; thus, it is recyclable and biodegradable. Because its raw material is an abundant natural resource, it can be obtained at low cost. Therefore, CNF is an excellent, green, next-generation nanomaterial. It has consequently become an area of intensive research around the world. Fuji Pigment Co., Kawanishi, Japan, has established a manufacturing process for CNF composite material (masterbatch) consisting of resins of acryl, polyethylene (PE), polyester, polypropylene(PP), poly vinyl chloride(PVC), etc. The company is also striving to produce composites using other plastic materials such as PS, ABS, etc.  

 

CNF is 4–20 nm in width and several micrometers in length, and it has a large aspect ratio. It weighs approximately a fifth of that of steel, but it is 7–8 times as strong. Its thermal expansion coefficient is low, comparable to that of glass fiber; however, its elasticity modulus is higher than that of glass fiber, making it a hard, strong, and robust material.  

When CNF is mixed with resin, it is therefore expected to strengthen the resin, and to contribute to its weight reduction. Also, it makes plastics biodegradable to some extent. Hence, CNF can be used as a material for automotive, aeronautic, architectural, and other applications, Fuji Pigment Co. points out. 

However, it adds, one of the problems with CNF that is commonly encountered by various researchers around the world is its high hydrophilicity, its numerous hydroxyl groups, and the consequent large number of water molecules bound to it, which pose difficulties in mixing it with most resins that are hydrophobic.  

To address the above problems, Fuji Pigment Co. has established a manufacturing process for mixing and dispersing CNF in various types of resins. For this effort, the company draws on years of experience with nanosize particle dispersion technology. The CNF concentration in the masterbatch is 3% –12%, depending on the resin mixture.  And still, the company is attempting to produce masterbatch mixtures with higher concentrations of CNF.  Furthermore, it is trying to produce CNF composite with biodegradable plastic such as poly lactic acid (PLA) and polybutylene succinate (PBS), to make reinforced 100% biodegradable plastic.  

Fuji Pigment Co., Ltd. has, in addition to masterbatch, CNF in water, as well as in organic solvents such as alcohol, pyrrolidone, glycol ether based solvent such as propyleneglycol monomethyl ether, and butyl cellosolve.  Dispersions in organic solvents based on ketones, hydrocarbons, and aromatic compounds seem particularly difficult to produce, although the company strives to achieve these. Besides strengthening various types of plastics, applications of CNF include those for various products such as cosmetics, membranes, filters, viscosity enhancers, catalyst carriers, separators, and biomedicine.

Fuji Pigment Co. supplies CNF in masterbatch solid form and as dispersions in water and liquid organic solvents. For more information, email Ryohei Mori.