Motivation

Acknowledgments

Innovation

Create a completely new and innovative idea that could be used through the process of flocking. This idea must increase the product range for high value-added products in lucrative markets. As a team, we plan on creating a post-surgical advanced wound care bandage that utilizes the absorbency properties of flocked fibers.

Advanced Wound Care Flocked Bandage Brielle Lombardi, Jasmine Cox, Caroline Paul

Fall 2013 Engineering & Technology Senior Design Department of Textile Engineering, Chemistry & Science, North Carolina State University, Raleigh, NC

Project Objective

Chitosan: • Comes from the shells of shellfish • Clots Blood • Naturally antimicrobial • Naturally antibacterial • Currently used in military Silver: • Naturally antibacterial • Naturally antimicrobial

Thank you to The American Flock Association, Dr. Willoughby, James Heracklis, Puritan Medical, Noble Biomaterials, Dow Corning, The AIF, and The Manufacturing Solutions Center.

Methodology

Business Model and Economics

Silver Nylon Bandage Chitosan Rayon Bandage Nylon Silver Flock (10 grams/bandage)

$1.10 Chitosan (1 gram/bandage)

$2.00

Silicone Adhesive $0.95 Rayon Flock (10 grams/bandage)

$0.40

Silicone Substrate (Sylgard 184, 10 grams/bandage)

$0.86 Silicone Adhesive $0.95

Silicone Substrate (Sylgard 184, 10 grams/bandage)

$0.86

Net Cost Per Bandage $2.91 Net Cost Per Bandage $4.21

Figure 1: Chitosan attached to Rayon Flock (scale 10 micrometers)

Figure 2: Nylon Impregnated with Silver Flocked Fibers (scale 200 micrometers)

Our Electrostatic Process 1. Our polydimethylsiloxane substrate is treated with a silicone adhesive from Dow

Corning. 2. Coated silicone substrate is placed onto an iron base connected to a high

electrostatic field. The base is connected to the ground wire. 3. The flocked fibers are placed in a plastic holder that is connected to an electrically

charged copper plate. The fibers are driven through a copper metal screen where they will become electrically charged.

4. The user then shakes the device to release the flocked fibers into the electrostatic field.

5. The electrically charged flocked fibers then become parallel with the electric field and magnetized towards the grounded electrode and the connected adhesive substrate.

6. Flocked fiber becomes entrenched in the adhesive silicone substrate. 7. The device is turned off and the substrate is then removed from the iron ground

base. Excess flocked fibers are removed through mechanical shaking. Figure 3: Electrostatic Flocking Station to

make samples

Figure 4: Schematic of the Hemostatic Medical Bandage © 2013 Brielle Lombardi, Caroline Paul, Jasmine Cox

Our Idea We would like to create an advanced wound care flocked bandage. Flocked fibers have a very high surface area, which would help to absorb as much blood as possible. Our bandage would include: 1. Substrate: Polydimethylsiloxane elastomer from Dow Corning

• This substrate is breathable and mimics the real texture of human skin adhesive:

2. Medical Grade Soft Skin Adhesive from Dow Corning 3. Flock:

• Rayon flock with Chitosan • Silver metalized Nylon 6,6

• Based upon the current cost of these bandages, the price would be considerably higher than most typical commercial bandages; however, would be profitable in post-surgical and military based scenarios.

Chitosan Rayon Bandage Comparison: • Competitor Price (Hemcon): $149.95/ 4x4 inch bandage • Our Price: $4.21/ 4x4 inch bandage • The difference in price gives room for production costs, marketing costs, and price mark-up for profit. Silver Nylon Bandage Comparison: • Competitor Price (Curad): $0.55/ 2x3 inch bandage • Our Price: $2.91/ 4x4 inch bandage • The bandage could be used for noncommercial applications, such as medical or military uses. • The price could be considered adequate in comparison to the advanced wound care products on the market today.

Results & Future Work

The advanced wound care team from senior design fall 2011/spring 2012 tried to use Nano fibers produced from high through-put electrospinning in order to create a hemostatic prototype with chitosan. The team was unable to complete the final product, which gave our team the idea to use flocked fibers as opposed to electrospun fibers in an advanced wound care bandage.

Absorbency Test: • Silver Nylon Bandage: hydrophobic with little to no absorption • Chitosan Rayon Bandage: Absorbed 1.8 grams of water in 10 minutes Fiber Alignment: • Silver Nylon Bandage: High alignment with little variation in fiber length (Figure 5) • Chitosan Rayon Bandage: Poor alignment and high fiber length variation (Figure 6) Future Work: • Test absorbency with synthetic blood • Dissolve chitosan in triacetic acid to coat fibers as a finish • Combine silver and rayon fibers to achieve higher absorbency

Figure 6: Chitosan Rayon Flock (scale 10 micrometers)

Figure 5: Nylon Impregnated with Silver Flocked Fibers (scale 200

micrometers)