Acrylic and para-aramid pulp and processes of making same
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Benefits of technology
Problems solved by technology
Method used
Image
Examples
first embodiment
I. First Embodiment of the Inventive Process
[0055] In a first embodiment, the process for making an acrylic and para-aramid pulp comprises the following steps. First, pulp ingredients are combined, added or contacted together. Second, the combined pulp ingredients are mixed to a substantially uniform slurry. Third, the slurry is simultaneously refined or co-refined. Fourth, water is removed from the refined slurry.
Combining Step
[0056] In the combining step, the pulp ingredients are preferably added together in a container. The pulp ingredients include (1) acrylic fiber, (2) para-aramid fiber, (3) optionally substantially or completely fibril-free, granular, para-aramid particles, (4) optionally other minor additives, and (5) water.
[0057] The acrylic fiber is added to a concentration of 10 to 90 wt % of the total solids in the ingredients, preferably 25 to 60 wt % of the total solids in the ingredients, and most preferably 25 to 55 wt % of the total solids in the in...
second embodiment
II. Second Embodiment of the Inventive Process
[0072] In a second embodiment, the process for making the acrylic fiber and para-aramid pulp is the same as the first embodiment of the process described above with the following differences.
[0073] Prior to combining all ingredients together, either the acrylic fiber or the para-aramid fiber, or both the acrylic fiber and the para-aramid fiber, may need to be shortened. This is done by combining water with the fiber ingredient. Then the water and fiber are mixed to form a first suspension and processed through a first disc refiner to shorten the fiber. The disc refiner cuts the fiber to an average length of no more than 10 cm. The disc refiner will also partially fibrillate and partially masticate the fiber. The other fiber, that was not previously added, can be shortened this way too forming a second processed suspension. Then the other fiber (or the second suspension, if processed in water) is combined with the first suspension.
[0074...
example 1
[0097] In this example of the invention, the pulp of this invention was produced from a feedstock of para-aramid fiber and acrylic staple. Acrylic staple having a cut length of 2 inches and having a filament linear density of 3 dpf (3.3 dtex per filament) was obtained from Solutia, Inc., with offices in St. Louis, Mo. Para-aramid fiber in the form of commercially available KEVLAR® brand floc, Style 1F178, having a ¼″ cut length, was obtained from E. I. de Pont de Nemours and Company with offices in Wilmington, Del.
[0098] Acrylic staple and water together were fed directly into a Sprout-Waldron 12″ Single Disc Refiner using a 10 mil plate gap setting and pre-pulped to reach an acceptable processing length in the range of 13 mm.
[0099] The pre-pulped acrylic fiber and the cut para-aramid fiber plus water were then combined into a highly agitated mixing tank at a solids concentration of 50 wt % para-aramid fiber and 50 wt % acrylic staple and mixed to form a uniform, pumpable slurry o...
PUM
| Property | Measurement | Unit |
|---|---|---|
| Length | aaaaa | aaaaa |
| Length | aaaaa | aaaaa |
| Length | aaaaa | aaaaa |
Abstract
Description
Claims
Application Information
Login to View More