Bituminous compositions prepared from thermoplastic polyolefins and their uses

Abstract

Bituminous compositions of the bitumen-polymer type, in homogenous phase, contain at least one bitumen base and are prepared from at least one polymer of the thermoplastic polyolefin type. These compositions have a thermoplastic polyolefin content of at least 1% by weight of which the crystallinity rate is greater than or equal to 30%, a melting temperature greater than or equal to 110° C. and a penetrability at 25° C. less than or equal to 300 tenths of a millimeter.

1 . Bituminous compositions of the bitumen-polymer type, in homogenous phase, containing at least one bitumen base and prepared from at least one polymer of the thermoplastic polyolefin type with a high molecular mass, said compositions being characterized by: 
 a content of at least 1% by weight of a thermoplastic polyolefin whose crystallinity rate is greater than or equal to 30%,    a melting temperature greater than to equal to 100° C., and    a penetrability at 25° C. that is less than or equal to 300 tenths of a millimete    
     
     
         2 . Bituminous compositions as set forth in  claim 1 , wherein the thermoplastic polyolefin is chosen from among the group consisting of the medium or high density polyethylenes, the polypropylenes, or the olefin copolymers.  
     
     
         3 . Bituminous compositions as set forth in  claim 1 , wherein the thermoplastic polyolefin has an average molecular mass by weight that is less than or equal to 60 000.  
     
     
         4 . Bituminous compositions as set forth in  claim 1 , wherein the polymer is obtained by partial degradation of a polyolefin such as a high density polyethylene or a polypropylene.  
     
     
         5 . Bituminous compositions as set forth in  claim 1 , wherein the polyolefin is a polyethylene whose crystallinity rate is greater than or equal to 500%.  
     
     
         6 . Bituminous compositions as set forth in  claim 1 , wherein the polyolefin is a polypropylene whose crystallinity rate is greater than or equal to 30% and, preferably, greater than or equal to 35%.  
     
     
         7 . Bituminous compositions as set forth in  claim 4 , wherein the polydispersity of the degraded polymer is reduced by approximately a factor 3 in relation to the original polymer.  
     
     
         8 . Bituminous compositions as set forth in  claim 4 , wherein the original polyolefin that has been degraded has an average molecular mass by weight ranging between 80 000 and 1 000 000 and preferably between 150 000 and 450 000.  
     
     
         9 . Bituminous compositions a set forth in  claim 1 , having a dynamic viscosity that is less than or equal to 3000 mPa.s, measured at 180° C. and a sheer rate of 50 s −1 .  
     
     
         10 . Bituminous compositions as set forth in  claim 1 , having a ball-ring temperature greater than or equal to 30° C.  
     
     
         11 . Bituminous compositions as set forth in  claim 1 , having a melting energy greater than or equal to 2 Joules/gram, and in particular ranging between 2 and 200 Joules/gram.  
     
     
         12 . Use of bituminous compositions as set forth in  claim 1 , with a thermoplastic polyolefin content ranging between 1 and 15% by weight, in paving applications, as anti-rutting coatings or as binder courses for roadways.  
     
     
         13 . Use of bituminous compositions as set forth in  claim 1 , with a thermoplastic polyolefin content ranging between 3 and 25% by weight in industrial applications, for the manufacture of sealing coats for roofs, insulation and soundproofing boards, or anti-corrosion coatings.