What is cellulose acetate?

Cellulose acetate is reacted from cellulose and acetic anhydride, in condition of catalyst and other additives. With acetic acid as solvent, the process of cellulose basically is heterogeneous reaction.

According to the degree of substitution(DS), Cellulose acetate can be commonly classified to  cellulose diacetate(DAC) and cellulose triacetate(TAC). Usually, DAC has DS with 2.2-2.5 while TAC has DS with above 2.7.(DS is an average number, It represents the number of –OH which is substituted by –C0CH3)

Fig.1  The molecular structure of cellulose acetate

Push Acetati can produce various kinds of product with different application, specification and properties(Include different viscosity/degree of polymerization, DS, clarity etc.)  to meet the  individual requirement of the customer.


Made with nature in mind

Cellulose acetate is an eco-friendly material that is manufactured from cellulose, a natural raw material obtained from well-managed forests that are conscientiously harvested and replanted with future generations in mind.

Furthermore, the process of cellulose acetate is carefully optimized towards reducing environmental impact at every stage by recovering and reusing solvent, water and energy and limiting the use of chemicals to the very minimum.


Biodegradability of cellulose acetate

Cellulose acetate is a kind of environmentally friendly products and much more biodegradable than aromatic polyesters and polypropylene.

Degradation of production is also a factor of sustainability. As for cellulose acetate, the degradation process can be generally divided into two steps:

1.First step, the removal of acetyl groups;

2. Then, the breakdown of the remaining cellulosic structures occurs.

Learn more about the biodergrability of cellulose acetate>>>>


Solubility of cellulose acetate

Usually, the solubility of cellulose acetate depends on the average degree of substitution, the distribution of substituents along the chain and the distribution on the primary and secondary –OH groups. The higher combined acetic acid, the poorer solubility.

Compared with other cellulose ester such as nitrocellulose, viscose cellulose, ethyl cellulose, etc., The solubility of cellulose acetate is poorer. It can be dissolved by only a few solvent.

Thanks to this property, the chemical resistance is superior. The typical solvent for cellulose triacetate is dichloromethane and the typical solvent for cellulose diacetate is acetone. 

Tab.1 The solubilit of cellulose diacetate in different solvents

Type of Solvent

Chemicals 

Solubility

Type of Solvent

Chemicals 

Solubility

Esters

Ethyl acetate

Aliphatics

Hexane, Heptane, ...

X

Butyl acetate

 X

Cyclohexane

X

Ethyl lactate

Alcohols

Ethanol

X

2-Ethoxyethyl acetate

Iso-Propanol

X

Ketones

Acetone

Diacetone alcohol

X

Methyl ethyl ketone

2-Methoxyethanol

X

Methyl isobutyl ketone

Others

Dimethyl formamide

Cyclohexanone

Dimethyl sulfoxide

Cyclic ethers

1,4-Dioxane

Methylene chloride

Tetrahydrofuran

Chloroform

Glycols

Ethylene glycol

1-Methyl-2-pyrrolidone

Ethylene glycol acetate

Mixtures of Esters & Alcohols

Ethyl acetate / Ethanol, 75/25

Hexylene glycol

X

Ethyl acetate / Ethanol, 50/50

X

Aromatics

Toluene, xylene

Ethyl acetate / Ethanol, 30/70

X

 


The application of cellulose acetate

Cellulose acetate around Xiaoming’s work place