Pipe Section having Polyarylene Sulfide Composition Barrier Layer

Abstract

Pipe sections and methods for forming pipe sections are disclosed. A pipe section includes a hollow body, the hollow body having an inner surface and an outer surface, the inner surface defining an interior. The pipe section further includes a barrier layer surrounding the hollow body, the barrier layer having an inner surface and an outer surface. The barrier layer is formed from a polyarylene sulfide composition. The polyarylene sulfide composition includes a polyarylene sulfide and a crosslinked impact modifier. Such pipe sections exhibit high strength characteristics and flexibility as well as resistance to degradation, even in extreme temperature environments, while maintaining desirable processing characteristics.

What is claimed is: 
     
         1 . A pipe section, comprising:
 a hollow body, the hollow body having an inner surface and an outer surface, the inner surface defining an interior;   a barrier layer surrounding the hollow body, the barrier layer having an inner surface and an outer surface, the barrier layer formed from a tape comprising a polyarylene sulfide composition, the polyarylene sulfide composition comprising a polyarylene sulfide and a crosslinked impact modifier.   
     
     
         2 . The pipe section of  claim 1 , wherein the polyarylene sulfide is polypropylene sulfide. 
     
     
         3 . The pipe section of  claim 1 , wherein the polyarylene sulfide is a functionalized polyarylene sulfide. 
     
     
         4 . The pipe section of  claim 1 , wherein the polyarylene sulfide composition has an elongation at yield of greater than about 7%. 
     
     
         5 . The pipe section of  claim 1 , wherein the polyarylene sulfide composition has a tensile modulus of less than about 2300 MPa. 
     
     
         6 . The pipe section of  claim 1 , wherein the polyarylene sulfide composition has a notched Charpy impact strength of greater than about 3 kJ/m 2  as measured according to ISO Test No. 179-1 at a temperature of 23° C. 
     
     
         7 . The pipe section of  claim 1 , wherein the polyarylene sulfide composition has a notched Charpy impact strength of greater than about 8 kJ/m 2  as measured according to ISO Test No. 179-1 at a temperature of −30° C. 
     
     
         8 . The pipe section of  claim 1 , wherein the crosslinked impact modifier comprises the reaction product of an epoxy functionality of the impact modifier and a crosslinking agent. 
     
     
         9 . The pipe section of  claim 1 , wherein the crosslinked impact modifier comprises the reaction product of maleic anhydride functionality of the impact modifier and a crosslinking agent. 
     
     
         10 . The pipe section of  claim 1 , wherein the polyarylene sulfide composition is free of plasticizers. 
     
     
         11 . The pipe section of  claim 1 , wherein the tape is wrapped generally helically around the hollow body with respect to a longitudinal axis of the hollow body. 
     
     
         12 . The pipe section of  claim 1 , wherein the polyarylene sulfide composition is fiber reinforced. 
     
     
         13 . The pipe section of  claim 12 , wherein the fibers are continuous fibers. 
     
     
         14 . The pipe section of  claim 13 , wherein the continuous fibers are generally unidirectional. 
     
     
         15 . The pipe section of  claim 1 , wherein the barrier layer is bonded to the hollow body. 
     
     
         16 . The pipe section of  claim 1 , wherein the barrier layer and hollow body are unbonded. 
     
     
         17 . The pipe section of  claim 1 , wherein the hollow body is formed from a thermoplastic material. 
     
     
         18 . The pipe section of  claim 17 , wherein the thermoplastic material is a polyarylene sulfide composition. 
     
     
         19 . The pipe section of  claim 18 , wherein the polyarylene sulfide composition includes a polyarylene sulfide and a crosslinked impact modifier. 
     
     
         20 . The pipe section of  claim 1 , wherein the hollow body is formed from a metal material. 
     
     
         21 . A pipe section, comprising:
 a hollow body, the hollow body having an inner surface and an outer surface, the inner surface defining an interior;   a barrier layer surrounding the hollow body, the barrier layer having an inner surface and an outer surface, the barrier layer comprising a continuous fiber reinforced polyarylene sulfide composition, the polyarylene sulfide composition comprising a polyarylene sulfide and a crosslinked impact modifier.   
     
     
         22 . The pipe section of  claim 21 , wherein the barrier layer is formed from a tape. 
     
     
         23 . The pipe section of  claim 21 , wherein the continuous fibers are generally unidirectional. 
     
     
         24 . A method for forming a pipe section, the method comprising surrounding a hollow body with a barrier layer such that the barrier layer is in contact with an outer surface of the hollow body, the barrier layer formed from a tape comprising a polyarylene sulfide composition, the polyarylene sulfide composition comprising a polyarylene sulfide and a crosslinked impact modifier. 
     
     
         25 . The method of  claim 24 , further comprising forming the polyarylene sulfide composition, wherein the forming step comprises:
 feeding the polyarylene sulfide to a melt processing unit;   feeding the impact modifier to the melt processing unit, the polyarylene sulfide and the impact modifier mixing in the melt processing unit such that the impact modifier becomes distributed throughout the polyarylene sulfide, the impact modifier comprising a reactive functionality; and   feeding a crosslinking agent to the melt processing unit, the crosslinking agent being fed to the melt processing unit following distribution of the impact modifier throughout the polyarylene sulfide, the crosslinking agent comprising reactive functionality that is reactive to the reactive functionality of the impact modifier.   
     
     
         26 . The method of  claim 25 , wherein the melt processing unit has a length L and a blending length L B , and wherein the ratio of L/L B  is from about 40 to about 1.1. 
     
     
         27 . The method of  claim 25 , further comprising feeding a disulfide compound to the melt processing unit, the disulfide compound comprising reactive functionality at terminal end(s) of the disulfide compound. 
     
     
         28 . The method of  claim 27 , wherein the reactive functionality of the disulfide compound is the same as the reactive functionality of the crosslinking agent. 
     
     
         29 . The method of  claim 27 , wherein the disulfide compound and the crosslinking agent are added in conjunction with one another. 
     
     
         30 . The method of  claim 25 , wherein the crosslinking agent is a disulfide-free crosslinking agent. 
     
     
         31 . The method of  claim 25 , wherein the impact modifier comprises an epoxy reactive functionality. 
     
     
         32 . The method of  claim 24 , further comprising:
 heating the barrier layer to a consolidation temperature; and   consolidating the hollow body and the barrier layer.   
     
     
         33 . The method of  claim 24 , wherein the surrounding step comprises wrapping the tape generally helically around the hollow body with respect to a longitudinal axis of the hollow body. 
     
     
         34 . The method of  claim 24 , wherein the polyarylene sulfide composition is fiber reinforced. 
     
     
         35 . The method of  claim 34 , further comprising forming the tape, the forming step comprising:
 flowing the polyarylene sulfide composition through a manifold assembly of a die, the manifold assembly comprising a plurality of branched runners;   coating at least one fiber roving with the polyarylene sulfide composition; and   traversing the coated roving through an impregnation zone of the die to impregnate the roving with the polyarylene sulfide composition.