Novel rheology regulators such as ground natural calcium carbonates optionally treated with a fatty acid or salt and their use

Abstract

The invention relates to the selection of a natural calcium carbonate crushed to a high degree of fineness, possibly treated with one or more fatty acids or one or more of their salts or mixtures thereof, and its use as a rheology regulator for polymeric compositions. The specific surface area is 14 to 30 m 2 /g measured according to the BET method to ISO 4652, and the oil absorption is greater than 16 measured according to ISO 787-V (Rub-out method). The conditions of mixing of the constituents and manufacture are improved, as well as the properties of the final product.

1 . A rheology regulator, characterised in that it is a case of a natural calcium carbonate, crushed to a high degree of fineness, with a specific surface area of around 14 to m 2 /g, preferably around 16 to 24 m 2 /g and highly preferentially around 20 m 2 /g, measured according to the BET method to ISO 4652.  
   
   
       2 . A rheology regulator according to  claim 1 , characterised in that it is a case of a natural calcium carbonate, crushed to a high degree of fineness, with a specific surface area of 14.4 m 2 /g, measured according to the BET method to ISO 4652.  
   
   
       3 . A rheology regulator according to  claim 1 , characterised in that it is a case of a natural calcium carbonate, crushed to a high degree of fineness, with a specific surface area of 16 m 2 /g, measured according to the BET method to ISO 4652.  
   
   
       4 . A rheology regulator according to  claim 1 , characterised in that it is a case of a natural calcium carbonate, crushed to a high degree of fineness, with a specific surface area of 16.5 m 2 /g, measured according to the BET method to ISO 4652.  
   
   
       5 . A rheology regulator according to  claim 1 , characterised in that it is a case of a natural calcium carbonate, crushed to a high degree of fineness, with a specific surface area of 22 m 2 /g, measured according to the BET method to ISO 4652.  
   
   
       6 . A rheology regulator according to  claim 1 , characterised in that it is a case of a natural calcium carbonate, crushed to a high degree of fineness, with a specific surface area of 22 m 2 /g, measured according to the BET method to ISO 4652.  
   
   
       7 . A rheology regulator according to any one of  claims 1  to  6 , characterised in that it is a case of natural calcium carbonate treated by means of at least one fatty acid containing 10 to 24 atoms of carbon or its salt chosen from amongst the salts of calcium, magnesium, zinc or a mixture thereof and more particularly using stearic acid or its calcium salt in a proportion of around 0.01% to 5% by weight.  
   
   
       8 . A rheology regulator according to  claim 7 , characterised in that it is a chase of a natural calcium carbonate treated by means of at least one fatty acid containing 10 to 24 atoms of carbon or its salt chosen from amongst the salts of calcium, magnesium, zinc or a mixture thereof and more particularly using stearic acid or its calcium salt in a proportion of around 1% to 4% by weight.  
   
   
       9 . A rheology regulator according to any one of  claims 1  to  8 , characterised in that it has an oil absorption which is greater than 16 measured according to ISO 787-V (Rub-out method).  
   
   
       10 . Use of a rheology regulator according to any one of  claims 1  to  9  for the preparation of sealants, adhesives or plastisols.  
   
   
       11 . Use of a rheology regulator according to any one of  claims 1  to  9  for the preparation of rubbers.  
   
   
       12 . Use as a rheology regulator, of dispersions or suspensions, in an organic medium, of a natural calcium carbonate crushed to a high degree of fineness according to any one of  claims 1  to  9  for the preparation of sealants or coatings, adhesives or plastisols.  
   
   
       13 . Use as a rheology regulator, of dispersions or suspensions, in an organic medium, of a natural calcium carbonate crushed to a high degree of fineness according to any one of  claims 1  to  9 , for the preparation of rubbers.  
   
   
       14 . A plastisol, characterised in that it comprises a rheology regulator according to any one of  claims 1  to  9 .  
   
   
       15 . A rubber, characterised in that it comprises a rheology regulator according to any one of  claims 1  to  9 .  
   
   
       16 . A sealant or coating or adhesive characterised in that it comprises a rheology regulator according to any one of  claims 1  to  9 .  
   
   
       17 . A sealant or coating or adhesive according to  claim 16 , characterised in that it comprises in addition a polyurethane with terminal silane groups and a plasticizer of the phthalate type.  
   
   
       18 . A sealant or coating or adhesive according to either one of claims  16  and  17 , characterised in that it comprises in addition one or more additives chosen from amongst smoked silica as a thixotropic agent, a bleaching agent such as TiO 2 , UV stablisers, adhesion promoter, a catalyst such as dibutyltin dilaurate, and dehydrating agents such as silane.