Process to produce microfibrillated cellulose by impacts

Abstract

The present invention relates a process to produce microfibrillated cellulose and a microfibrillated cellulose produced according to such process. The fibrillated microfibrillated cellulose is obtained subjecting a cellulose fiber in a slurry of cellulose pulp to multiple mechanical impacts. The cycle may be repeated several times. Non-cutting bars disposed in a ring formation is the preferred method. Two rings concentrically arranged facing each other in high rotation transmit the kinetic energy to the fibers to provide the highly defibrillated microfibrillated cellulose.

1 . A microfibrillated cellulose produced with a process comprising the following steps:
 a. providing a slurry comprising cellulose fibers,   b. subjecting the slurry to defibrillation under continuous impacts to produce microfibrillated cellulose comprised of microfibrils.   
     
     
         2 . The microfibrillated cellulose according to  claim 1 , wherein the microfibrillated cellulose is produced without the use of enzymatic or chemical treatments, wherein the slurry is subjected to continuous impacts from 5 to 240 minutes, and wherein the produced highly microfibrillated cellulose at 0.85% wt. in water comprises a dynamic viscosity from 15-1000 mPas·s. 
     
     
         3 . The microfibrillated cellulose according to  claim 1 , wherein the microfibrils of the microfibrillated cellulose have a diameter from about 0.01 μm to 0.8 μm. 
     
     
         4 . The microfibrillated cellulose according to  claim 1 , wherein the microfibrils of the microfibrillated cellulose have an average diameter of 0.1 μm, determined by scanning electron microscopy. 
     
     
         5 . The microfibrillated cellulose according to  claim 1 , wherein the fibers are microfibrillated cellulose, nanofibrillated cellulose, or mixtures thereof. 
     
     
         6 . The microfibrillated cellulose according to  claim 1 , wherein the microfibrils of the microfibrillated cellulose have a diameter from about 0.01 μm to 0.8 μm, and wherein the microfibrillated cellulose at 0.85% wt. in water comprises a dynamic viscosity from 15-1000 mPas·s. 
     
     
         7 . A microfibrillated cellulose comprising microfibrils having an average diameter from about 0.01 μm to 0.8 μm. 
     
     
         8 . The microfibrillated cellulose according to  claim 7 , wherein the microfibrillated cellulose at 0.85% wt. in water comprises a dynamic viscosity from 15-1000 mPas·s. 
     
     
         9 . The microfibrillated cellulose according to  claim 7 , wherein the microfibrils have an average diameter of 0.1 μm, determined by scanning electron microscopy. 
     
     
         10 . The microfibrillated cellulose according to  claim 7 , wherein the microfibrils are microfibrillated cellulose, nanofibrillated cellulose, or mixtures thereof. 
     
     
         11 . The microfibrillated cellulose according to  claim 7 , wherein the microfibrils are derived from Kraft fibers, bleached cellulose fibers, semi-bleached cellulose fibers, unbleached cellulose fibers, dry cellulose fibers, never dry cellulose fibers or mixtures thereof. 
     
     
         12 . A slurry comprising water and a microfibrillated cellulose comprising microfibrils having an average diameter from about 0.01 μm to 0.8 μm. 
     
     
         13 . The slurry according to  claim 12 , wherein at a microfibrillated cellulose concentration of 0.85% wt. in water, the slurry exhibits a dynamic viscosity from 15-1000 mPas·s. 
     
     
         14 . The slurry according to  claim 12 , wherein the microfibrils have an average diameter of 0.1 μm, determined by scanning electron microscopy.