Biodegradable composition for preparing table-ware, mulching film and package and method for preparing the same

Abstract

The present invention relates to a biodegradable composition for the preparation of table-ware, mulching film and package, which comprises: 2-6% by weight of starch; 35-45% by weight of plant powders; 20-30% by weight of calcium carbonate; 2-7% by weight of sorbital; 7-13% by weight of polypropene; 2-5% by weight of polyethylene; 2-6% by weight of coupling agent; 1-2% by weight of defoamer; 2-5% by weight of stearic acid; 2-6% by weight of stearate; 3-6% by weight of glycerine or epoxidized soybean oil; and 60-100 ppm photosensitizer. The present invention also relates to a method for preparing the composition, which comprises: treating a plant wastes with a diluent acid, drying and pulverizing, then mixing it with starch, polypropene, and polyethylene, sorbital, defoamer, coupling agent, stearic acid, stearate, glycerine and photosensitizer homogeneously; blending the mixture obtained in a double-screw extruder at a temperature of 160-180 C to obtain the composition of the present invention.

1 . A biodegradable composition for the preparation of table-ware, drink containers, mulching film and package, comprising: 
 2-6% by weight of starch;    35-45% by weight of plant powders;    20-30% by weight of calcium carbonate;    2-7% by weight of sorbital;    7-13% by weight of polypropene;    2-5% by weight of polyethylene;    2-6% by weight of coupling agent;    1-2% by weight of defoamer;    2-5% by weight of stearic acid;    2-6% by weight of stearate;    3-6% by weight of glycerine or epoxidized soybean oil; and    60-100 ppm photosensitizer.    
     
     
         2 . The composition according to  claim 1 , comprising: 
 3-5% by weight of starch;    35-40% by weight of plant powders;    20-30% by weight of calcium carbonate;    4-6% by weight of sorbital;    8-11% by weight of polypropene;    3-4% by weight of polyethylene;    3-5% by weight of coupling agent;    1-2% by weight of defoamer;    3-4% by weight of stearic acid;    3-5% by weight of stearate;    3-5% by weight of glycerine or epoxidized soybean oil; and    60-100 ppm photosensitizer.    
     
     
         3 . The composition according to  claim 2 , comprising: 3% by weight of starch; 37% by weight of plant powders; 25% by weight of calcium carbonate; 5% by weight of sorbital; 9% by weight of polypropene; 3% by weight of polyethylene; 5% by weight of coupling agent; 4% by weight of stearic acid; 4% by weight of stearate; 1% by weight of defoamer; 4% by weight of glycerine or epoxidized soybean oil and 60 ppm photosensitizer.  
     
     
         4 . The composition according to  claim 1 ,  2  or  3 , wherein the starch includes corn starch, potato starch, ipomoea batatas starch, cassava starch and their modified starch with a grain size of larger than 70 mesh.  
     
     
         5 . The composition according to  claim 1 ,  2  or  3 , wherein, the plant powder is the powder of one or more plants in sugar cane residue, peanut shell, dry pine needle, rice husk, millet bran and soybean shell.  
     
     
         6 . The composition according to  claim 1 ,  2  or  3 , wherein, the calcium carbonate is light or heavy calcium carbonate with a grain size of larger than 70 mesh.  
     
     
         7 . The composition according to  claim 1 ,  2  or  3 , wherein, the coupling agent is silane.  
     
     
         8 . The composition according to  claim 1 ,  2  or  3 , wherein, the stearate is ferrite stearate, magnesium stearate or calcium stearate.  
     
     
         9 . The composition according to  claim 1 ,  2  or  3 , wherein, the stearate is ferrite stearate.  
     
     
         10 . The composition according to  claim 1 ,  2  or  3 , wherein, the photosensitizer is benzophenone.  
     
     
         11 . The composition according to  claim 1 ,  2  or  3 , wherein, the defoamer is emulsified silicone oil.  
     
     
         12 . A method for preparing a biodegradable composition for the preparation of table-ware, mulching film and package, comprising: 
 (1) treating one or more plant wastes selected from the group consisting of sugar cane residue, peanut shell, dry pine needle, rice husk, millet bran and soybean shell soaked in a 0.2-1.0% by weight of sulfuric acid or hydrochloric acid solution for 2-10 hours to degrease and modify and to wash, and then drying the same to let it have a water content of less than 10%; mixing the obtained plant wastes with starch, sorbital, polypropene, and polyethylene, and pulverizing the obtained mixture to obtain a powder with a particle size of less than 70 mesh; mixing the obtained powder with calcium carbonate, stearic acid, stearate, coupling agent, defoamer, glycerine or epoxidized soybean oil and photosensitizer homogeneously;    (2) blending the mixture obtained in step(1) in a double-screw extruder at a temperature of 160-180 C to obtain the composition of the present invention.