Fiber Reinforced Cellular Foam Product

Abstract

Fiber reinforced polymer foam articles are disclosed. Through the system and process of the present disclosure, fibers can be incorporated into the foam article during an injection molding process while minimizing fiber breakage. Thus, foam articles can be produced having relatively long fibers. For instance, when using a feed stock containing fibers having a length greater than about 0.7 cm, such as from about 1 cm to about 1.3 cm, foam articles can be produced in which at least about 10% by volume of the fibers have a length greater than 3 mm and wherein at least about 1% by volume of the fibers have a length greater than about 7 mm.

1 . A polymer composite article comprising:
 a polymer matrix comprising a thermoplastic polymer, the polymer matrix having a cellular structure; and   fibers dispersed in the polymer matrix, the fibers being present in the polymer matrix in an amount of at least about 10 percent by weight, wherein at least 10 percent of the fibers by volume have a length of greater than about 3 mm and wherein at least about 10 percent of the fibers by volume have a length of from about 3 mm to about 4 mm.   
   
   
       2 . (canceled) 
   
   
       3 . A polymer composite article as defined in  claim 1 , wherein at least some of the fibers have a length greater than 6 mm. 
   
   
       4 . A polymer composite article as defined in  claim 1 , wherein at least 1 percent of the fibers by volume have a length of greater than about 7 mm. 
   
   
       5 . A polymer composite article as defined in  claim 1 , wherein the fibers comprise glass fibers. 
   
   
       6 . A polymer composite article as defined in  claim 1 , wherein the thermoplastic polymer comprises a polyolefin, a polyamide, or mixtures thereof. 
   
   
       7 . A polymer composite article as defined in  claim 1 , wherein the article has a void volume of at least about 5 percent. 
   
   
       8 . A polymer composite article as defined in  claim 1 , wherein the article has a void volume of at least about 10 percent. 
   
   
       9 . A polymer composite article as defined in  claim 1 , wherein the polymer matrix contains a plurality of cells, the cells having an average cell size of less than about 100 microns. 
   
   
       10 . A polymer composite article as defined in  claim 1 , wherein the article has been injection-molded. 
   
   
       11 . A polymer composite article as defined in  claim 1 , wherein the polymer matrix has a cell density of at least about 10 6  cells per cubic centimeter. 
   
   
       12 . A polymer composite article as defined in  claim 1 , wherein the article has a drop impact of greater than about 7 ft-lb and has a notched impact of greater than about 2.5 ft-lb/in 2 . 
   
   
       13 . A polymer composite article as defined in  claim 1 , wherein the fibers dispersed in the polymer matrix have an average fiber length of greater than about 1.25 mm. 
   
   
       14 . A polymer composite article as defined in  claim 1 , wherein the fibers comprise talc fibers, wollastonite fibers, carbon fibers, metal fibers, aromatic polyamide fibers, or mixtures thereof. 
   
   
       15 . A polymer composite article as defined in  claim 1 , wherein the fibers are present in the polymer matrix in an amount from about 20% to about 60% by weight. 
   
   
       16 . A polymer composite article comprising:
 a polymer matrix comprising a thermoplastic polymer, the polymer matrix having a cellular structure; and   fibers dispersed in the polymer matrix, the fibers being present in the polymer matrix in an amount of at least about 10% by weight, and wherein at least 1 % of the fibers by volume have a length of greater than about 6.5 mm, and wherein at least about 1 percent of the fibers by volume have a length of from about 3 mm to about 7 mm.   
   
   
       17 . A polymer composite article as defined in  claim 15 , wherein at least about 10% of the fibers by volume have a length greater than about 3 mm and wherein the fibers have an average length of greater than about 1.25 mm. 
   
   
       18 . A polymer composite article as defined in  claim 16 , wherein the article has a void volume of at least about 5%. 
   
   
       19 . A polymer composite article as defined in  claim 16 , wherein the thermoplastic polymer comprises a polyolefin, a polyamide, or mixtures thereof and wherein the fibers comprise glass fibers. 
   
   
       20 . A polymer composite article as defined in  claim 16 , wherein the article has a drop impact of greater than about 7 ft-lb and has a notched impact of greater than about 2.5 ft-lb/in 2 . 
   
   
       21 . A polymer composite article as defined in  claim 16 , wherein the article has been injection-molded.