Method of forming composite articles
View Patent ↗A method for forming a composite article includes injecting first and second compositions into a die head at different points so as to produce a partially mixed composition that is discharged from the die head. The second composition contains less filler material than the first composition.
1. A method of forming a non-laminated composite article, said method comprising:
providing a die head having an outlet;
injecting a first composition into said die head at a first point to create a first stream, said first composition comprising a combination of matrix and cellulosic filler materials;
injecting a second composition into said die head at a second point to create a second stream, said second composition containing less cellulosic filler material than said first composition, and wherein said second point is located relative to said outlet so as to permit a desired degree of mixing between said first and second streams so as to produce a partially mixed composition stream; and
discharging said partially mixed composition stream through said outlet, wherein said desired degree of mixing is such that discharging said partially mixed composition stream through said outlet forms a non-laminated composite article, said non-laminated composite article having a first region that encompasses a surface of said non-laminated composite article and comprises a mix of said first and second compositions and a second region that comprises only said first composition, and wherein said cellulosic filler material is distributed in said first region so as to present a density gradient throughout said first region with a minimum filler density at said surface of said non-laminated composite article.
2. The method of claim 1 wherein said second point is located upstream of said outlet a predetermined distance which is sufficient to allow said desired degree of mixing.
3. The method of claim 1 wherein said second composition includes one or more additives.
4. The method of claim 1 wherein said second region comprises approximately 60% filler material by weight and said first region comprises approximately 1-2% filler material by weight.