Non-Skid Coatings

1
Non Skid Coating Formulation Utilizing a Design
of Experiments (DOE) Approach
TRFA Annual Meeting, Boston MA 4 October
2004 Charles S. Tricou Applied Research
Laboratory The Pennsylvania State University
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Overview

• Repair and Replacement
• Repair is time-, material-, and labor-intensive.
• Repair costs Range from 13- 25 /ft2
• CV 63 (November 2000)
• 116,000 ft2
• Labor 22.50 / ft2
• Material 2.80 / ft2
• CVN 72 (April 2004)
• 70,000 ft2
• Cost 1.4 Million (20 / ft2 )

• Durability
• Approximately 80 of CVN flight deck nonskid
  coatings are replaced following each deployment.
  Extending the durability and functionality of
  nonskid coatings to last through 2 full
  deployments will save the Navy 5M per year.
• Nonskid coatings in arrested landing areas are
  removed and replaced 2 or 3 times per deployment
  cycle.
• Flight deck coatings have degraded during
  deployment to an extent necessitating repair.
  Repairs at foreign ports are very expensive and
  result in temporary loss of platform availability.

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Future Research / Growth

• Arrested Landing Area
• Eliminate erosion of non-skid coating due to wire
  slap
• Protect arresting cable from abrasion damage
• Reduce or eliminate damage to nonskid coating
  from tail-hook impact
• Submarine Topside
• Develop durable nonskid for continuous seawater
  immersion

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Approach

• Develop a high-performance organic nonskid system
• Utilize multiple types of high-performance
  abrasives in conjunction with the development /
  refinement of modern epoxy and epoxy/urethane
  blends to achieve maximum nonskid functionality,
  strength, durability, chemical resistance and
  corrosion protection.
• Advanced epoxy blends and rapid-cure polymer
  technology
• State-of-the-art ceramic technology (material,
  shape, chemistry)
• A robust design of experiments approach will be
  used to identify the key parameters affecting all
  aspects of nonskid coating performance, and
  enable optimization of the nonskid system.
• This approach offers the potential of achieving
  maximum performance from an organic-based nonskid
  coating. After qualification, such a system may
  be used as a drop-in replacement for current
  epoxy-based systems.

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Performance Measurements (Outputs)

• Coating performance measurements
• Adhesion
• Corrosion (QUV, Salt Fog, Immersion, etc.)
• Service-specific durability tests
• Erosion
• Impact Resistance
• Chemical Resistance

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DOE Approach What is it?

• Design of Experiments (DOE) is a scientific
  approach to experimentation. A good DOE will
  yield the following benefits
• Aid in the selection and isolation of the
  important variables to be studied
• Minimize the number of experiments that must be
  carried out to yield meaningful results
• Maximize the amount of information that can be
  extracted from the experiments
• Minimize the cost of product development and
  process control

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DOE How it Works 2-Factor (full factorial)
Linear
Provides information about interactions

• Linear Design
• 2 levels for each factor
• 2n trials
• For 2 factors n 2
  

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2-Factor (full factorial) Quadratic

• Non-Linear Design
• 3 levels for each factor
• 3n trials
• For 2 factors n 2
  

Factor 2
Factor 1
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3-Factor (full factorial) Linear
Factor 2

• Linear Design
• 2 levels for each factor
• 2n trials
• For 3 factors n 3
  

Factor 1
Factor 3
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Mixture Designs

• Constraints
• C1 C2 C3 Fixed

Component 1
Binary Blend
Component 3
Component 2
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Non Skid Formulation Components Levels

• Components (Levels)
• Polyamine Curing Agent 1 (Stoich)
• Polyamine Curing Agent 2 (Stoich)
• Modifier 1 (0 30 by weigh of Resin)
• Modifier 2 (0 30 by weight of Resin)
• Modifier 3 (0 30 by weight of Resin)
• Adhesion Promoter 1 (0 0.5 by weight of
  Resin)
• Adhesion Promoter 2 (0 0.5 by weight of
  Resin)
• Base Resin (100 grams)

Constraints Total Modifier cannot exceed 30 0
C D E 30 grams
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Design Strategy
Ideally, this design would have been performed
utilizing a mixture design. However, this is
exceptionally difficult to do using the
commercial software available. In mixture
design, the component ranges are defined
according to weight contribution or volume
contribution. In epoxy formulations, equivalent
contributions can also be used. These
contributions should be expressed as percentages
of the total mixture. In this study, the
constraints are such that it was not possible to
create a mixture design utilizing the available
software. Consequently, we opted to perform this
formulation study in the manner of a factorial
experiment.
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Design Strategy
In total, there are 8 potential components that
may be used in the coating formulation. However,
the amount of base resin used in each trial is
held constant at 100 grams. Since the amount of
resin does not vary, the base resin may be
eliminated as a variable, reducing the number of
variables to 7. The actual levels of the
polyamine curing agents are determined by
stoichiometry. Because of stoichiometric
constraints, the amount of one curing agent used
will depend upon the amount of the other curing
agent used. By defining the amount of one of the
curing agents as a fraction of the total curing
agent used, the other curing agent is eliminated
as a variable. This reduces the total number of
variables from 7 to 6.
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Design Strategy
A quadratic D-Optimal design was chosen for this
experiment. The D-Optimal design provides
substantial information with a a minimum number
of trials.

• Components (Levels)
• Polyamine Curing Agent 1 (Fraction of total
  curing agent used 0 - 1)
• Polyamine Curing Agent 2 (Stoich, based on
  amount of PCA1)
• Modifier 1 (0 30 by weigh of Resin)
• Modifier 2 (0 30 by weight of Resin)
• Modifier 3 (0 30 by weight of Resin)
• Adhesion Promoter 1 (0 0.5 by weight of
  Resin)
• Adhesion Promoter 2 (0 0.5 by weight of
  Resin)
• Base Resin (100 grams)

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D-Optimal Design 38 Total Trials
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D-Optimal Design 38 Total Trials First 13 trials
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Conversions
Trial 1
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Experimental Design
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D-Optimal Design 38 Total Trials First 13 trials
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Expected Outcome

• Within the design space defined by these
  components and by the levels of these components,
  we expect to identify formulations having the
  maximum possible performance for each of the
  performance criteria that we plan to measure.
• Toughness / Impact resistance
• Adhesion
• Corrosion
• Chemical Resistance
• We expect to be able to model the effect on
  coating performance resulting from varying the
  concentration of these components.
• We expect to utilize this model to identify a
  coating formulation capable of meeting the
  project goals.

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Team Participants
Applied Research Laboratory Epoxy Chemicals,
Inc. Advanced Systems Technologies, Inc.
(AST) St. Gobain Mineral Abrasives