The difference between nanocellulose and microcrystalline cellulose

Nanocellulose and microcrystalline cellulose (MCC) are both derived from natural cellulose, but they are significantly different in structure, preparation method, physical and chemical properties and application fields. Here are the main differences between them:

1. Definition and structure

1. Nanocellulose

oDefinition : Nanocellulose refers to a nanoscale material composed of cellulose molecules, usually including cellulose nanofiber filaments (CNF) and cellulose nanocrystals (CNC) Its size is generally at the nanometer level, its diameter is usually between a few nanometers and tens of nanometers, and its length can reach several microns or even longer..

oStructure : Nanocellulose can be manifested as long fibrous (CNF) or short rod (CNC), with a highly dispersed fibrous structure It has a high specific surface area and a high degree of mechanical strength..

2. Microcrystalline cellulose (MCC)

oDefinition : Microcrystalline cellulose is a pure cellulose powder obtained by partial acid hydrolysis of natural cellulose. Its size is usually at the micron level, with crystalline and non-crystalline regions.

oStructure : The structure of MCC is mainly composed of crystalline regions of cellulose, which remove the non-crystalline portions by partial hydrolysis, forming shorter cellulose chains. It usually appears in powder form, with particle sizes ranging from tens of microns to hundreds of microns.

2. Preparation method

1. Nanocellulose

o Preparation method : Nanocellulose can be extracted from natural cellulose by mechanical decomposition, enzymatic decomposition, acid hydrolysis and other methods. Cellulose nanofiber filaments (CNF) are mainly obtained by mechanical or enzymatic methods, while cellulose nanocrystals (CNCs) are mainly prepared by acid hydrolysis.

2. Microcrystalline cellulose

o Preparation method : Microcrystalline cellulose is partially acid-hydrolyzed by removing non-crystalline amorphous regions and retaining crystalline regions, thereby obtaining cellulose particles with microcrystalline structure.

III. Physical and chemical properties

1. Nanocellulose

oSize : The size of nanocellulose is at the nanoscale and has a very high specific surface area.

oMechanical properties : Nanocellulose has high mechanical strength and rigidity, especially cellulose nanocrystals (CNCs), which exhibit excellent strength due to their high crystallization.

oDisperity : Nanocellulose usually has good dispersion in water and can form a stable colloidal solution .

2. Microcrystalline cellulose

oSize : The size of microcrystalline cellulose is in the micron scale, usually from a few microns to tens of microns.

oMechanical properties : Compared with nanocellulose, microcrystalline cellulose has lower mechanical strength, but still has better fluidity and fillability.

oDisperity : Microcrystalline cellulose usually appears in powder form and can be dispersed in liquid, but its dispersion is not as good as nanocellulose and is easy to precipitate.

IV. Application fields

1. Nanocellulose

oApplication fields : Nanocellulose is widely used in fields such as reinforced composite materials, biomedicine, food packaging, environmentally friendly materials, sensors, filter membranes, etc. due to its unique mechanical properties and surface chemical properties. Its high specific surface area and good mechanical properties make it have great potential in high-performance materials.

2. Microcrystalline cellulose

oApplication fields : Microcrystalline cellulose is widely used in the pharmaceutical industry (as an excipient for tablets), food industry (as a thickener and stabilizer), cosmetics, papermaking and other fields. Its good fluidity, water absorption and stability make it ideal for many industrial applications.

5. Summary of the main differences

1. Size : The size of nanocellulose is at the nanoscale, while the size of microcrystalline cellulose is at the microscale.

2. Structure : Nanocellulose has a high specific surface area and a highly crystallized fiber structure, while microcrystalline cellulose is mainly composed of partial crystalline areas and is in powder form.

3. Mechanical properties : The mechanical strength of nanocellulose is significantly higher than that of microcrystalline cellulose, and it has advantages especially in high-performance materials applications.

4. Application fields : Nanocellulose is more widely used, especially in high-performance materials and emerging technologies, while microcrystalline cellulose is mainly used in traditional industries such as pharmaceuticals, food and papermaking.

The selection of nanocellulose and microcrystalline cellulose should be determined based on specific application requirements and material characteristics.