Synthetic plastic composition, articles made therefrom and method of manufacture

Abstract

New plastic compositions, made from a uniform mixture of thermoplastic resin and a naturally occurring aluminosilicate glass (NOAG) produce articles of manufacture by a variety of molding processes that have a more uniform and smoother surface with significantly reduced sink marks, and exhibit an improved dispersion of additives and pigments. The molding machines making articles from these compositions of thermoplastic resin and NOAG exhibit an increase in throughput, lower operating temperatures, less power consumption, reduced injection pressure, and increased injection speed. Running these synthetic plastic compositions through injection, extrusion and blow molding machines also tends to clean and lubricate the screw and the injector nozzles, increasing the life of the machine parts. The NOAG is preferably present in amounts ranging from 0.1% to 3.0% by weight of the composition. The NOAG is added to the thermoplastic resin in a manner that uniformly disperses it throughout the resulting thermoplastic resin-NOAG composition. The NOAG may be added as a dry powder directly to the plastic resin preferably in a particle size smaller than 325 mesh. The NOAG also may be added to the plastic resin in pellet form of various sizes, encapsulated by a carrier such as LLDPE, or may be directly compounded into the thermoplastic resin.

1 . A composition comprising 
 a plastic resin; and    a predominately vitreous, naturally occurring formulation: 
 Silicon Dioxide (SiO 2 )—about 73.0%,  
 Aluminum Oxide (Al 2 O 3 ) and  
 other oxides and trace minerals each less than about 5.0%, the formulation being in a quantity of less than about 2% by weight of the composition.  
   
   
   
       2 . The composition of  claim 1 , the predominately vitreous formulation being in a quantity greater than about 0.5% by weight of the composition.  
   
   
       3 . The composition of  claim 1 , the predominately vitreous formulation being predominantly in a particle size range below about 75 microns.  
   
   
       4 . An article of manufacture made from a composition comprising a plastic resin; and 
 a predominately vitreous material comprising silicon dioxide and aluminum oxide uniformly dispersed throughout the composition, the material comprising silicon dioxide and aluminum oxide being in a quantity of less than about 2% by weight of the composition to improve flow in the formation of the article.    
   
   
       5 . The article of manufacture of  claim 4 , the predominately vitreous material comprising silicon dioxide and aluminum oxide being in a quantity greater than about 0.5% by weight of the composition.  
   
   
       6 . The article of manufacture of  claim 4 , the predominately vitreous material comprising silicon dioxide and aluminum oxide being predominantly in a particle size range below about 75 microns.  
   
   
       7 . A method for forming articles, comprising 
 selecting a plastic resin;    dispersing a predominately vitreous material comprising silicon dioxide and aluminum oxide uniformly throughout the selected plastic resin to form a composition, the material comprising silicon dioxide and aluminum oxide being in a quantity of less than about 2% by weight of the composition to improve flow in the formation of the articles; and    forming articles by flowing the composition under pressure.    
   
   
       8 . The method of  claim 7 , the predominately vitreous material comprising silicon dioxide and aluminum oxide being in a quantity of greater than about 0.5% by weight of the composition.  
   
   
       9 . The method of  claim 7 , the predominately vitreous material comprising silicon dioxide and aluminum oxide being predominantly in a particle size range below about 75 microns.  
   
   
       10 . The method of  claim 7 , the material comprising silicon dioxide and aluminum oxide dispersed being naturally occurring.  
   
   
       11 . A composition for the formation of articles, comprising 
 a plastic resin; and    a predominately vitreous material comprising silicon dioxide and aluminum oxide uniformly dispersed throughout the composition, the material being in a quantity of less than about 2% by weight of the composition to improve flow in the formation of the articles.    
   
   
       12 . The composition of  claim 11  therein the vitreous material is in a quantity greater than about 0.5% by weight of the composition.  
   
   
       13 . The composition of  claim 12  further comprising 
 a carrier for the predominately vitreous material.    
   
   
       14 . The composition of  claim 13 , the predominately vitreous material being in pellet form with the carrier before dispersion within the composition.  
   
   
       15 . The composition of  claim 11 , the predominately vitreous material being predominantly in a particle size range below about 75 microns.  
   
   
       16 . The composition of  claim 11 , the predominately vitreous material being naturally occurring.