Technology

Brief description

Cellulose is the most abundant renewable natural polymer on Earth, which cab be used as an input material for the regenerated cellulose film production. It is considered to be a virtually inexhaustible source of raw material. However, native cellulose cannot be processed via melt spinning. Cellulose is insoluble in water as well as in most common organic solvents because of the strong hydrogen bonds that occur between cellulose chains. As a result, to successfully process cellulose, either chemical derivatization or physical dissolution in an appropriate solvent is required.

There is a paradox in the manufacture of man-made films that one of the cleanest film types, i.e. regenerated cellulose film, is not produced by environmentally acceptable methods. The historically first and the most widely used regeneration method, called the xanthate process or viscose process, is notorious for air and water pollution and the use of hazardous carbon disulfide. It is necessary to emphasize that this process generate highly toxic sewage and gas emissions which are harmful to the environment. For instance, approximately 50% of the carbon disulfide ends up as a waste product. Meanwhile the high demand for cellophane products does not allow its full exclusion.

Because of the environmental issues, the viscose process is becoming less and less common now. To meet the environmental policy requirements many organic solvent systems such as N-methylmorpholine-N-oxide, dimethylformamide-nitrogen oxide, dimethylacetamide-lithium chloride and some others have been proposed and investigated. Despite of the fact that these solvent systems are progressive to the viscose process they have plenty of disadvantages and problems. Their main advantage is the absence of toxic gases. However, disadvantages touch on high cost, complicated dissolving procedure, extreme when recovering solvents and poor industrial application.

Many processes to prepare a regenerated cellulose film from the natural cellulose have been developed, but merely some of them have been applied to industry.

We have recently developed a highly advanced technology called EcoBioFilm, which provides many advantages to the regenerated cellulose fiber industry. New concept and “green” approach for dissolution of cellulose have been proposed as a quite real alternative to the viscose process. According to novel process, the aqueous solutions of orthophosphoric acid can be used as the efficient cellulose solvents.

Novel technology can move packaging industry towards sustainable development and promote eco-efficiency, innovation, new methods and tools for plastic free packaging.