ARL-SR-0371 ● Apr 2017

ARL-ADHES-QA-001.02 Rev 1.0

US Army Research Laboratory

Adhesives: Test Method, Group Assignment, 

and Categorization Guide for High-LoadingRate Applications – History and Rationale

by Robert Jensen, David Flanagan, Daniel DeSchepper, and 

Charles Pergantis

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Army position unless so designated by other authorized documents.

Citation of manufacturer’s or trade names does not constitute an official

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Destroy this report when it is no longer needed. Do not return it to the originator.
ARL-SR-0371 ● Apr 2017

ARL-ADHES-QA-001.02 REV 1.0

US Army Research Laboratory

Adhesives: Test Method, Group Assignment, 

and Categorization Guide for High-LoadingRate Applications – History and Rationale

by Robert Jensen, David Flanagan, Daniel DeSchepper, and 

Charles Pergantis

Weapons and Materials Research Directorate, ARL

Coatings, Corrosion, and Engineered Polymers Branch (CCEPB)*

*CCEPB is ISO 9001:2008 Certified by SRI Quality Systems Registrar

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Adhesives: Test Method, Group Assignment, and Categorization Guide for HighLoading-Rate Applications – History and Rationale

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Robert Jensen, David Flanagan, Daniel DeSchepper, and Charles Pergantis

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ARL-ADHES-QA-001.02 Rev 1.0

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Send comments or inquiries to: usarmy.APG.arl.mbx.adhesive-research@mail.mil 

14. ABSTRACT

This report provides the development history and rationale for the standard process description ARL-ADHES-QA-001.00 Rev 

1.0, Adhesives: Test Method, Group Assignment, and Categorization Guide for High Loading Rate Applications, by the 

Adhesives and Informatics Team, Coatings, Corrosion and Engineered Polymers Branch, US Army Research Laboratory.

15. SUBJECT TERMS

adhesives, history, invention, innovation, technology development, informatics, standardization, relational database

16. SECURITY CLASSIFICATION OF:

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Robert E Jensen

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Contents

List of Figures iv

1.0 Purpose 3

2.0 Scope 3

3.0 Policy 8

4.0 Responsibilities 8

5.0 Requirements 8

6.0 Terms and Definitions 8

7.0 Records 8

8.0 Appendix A. Innovation vs. Invention 9

9.0 Appendix B. Technological Development Curves 11

10.0 Appendix C. Development History of Aviation Adhesives 13

11.0 Acknowledgments 17

12.0 References 18

List of Symbols, Abbreviations, and Acronyms 27

Distribution List 28
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iv

List of Figures

Fig. 1 Adhesive groups based upon single-lap-joint performance (Smax and 

dfailure) at RT (dry conditioning)............................................................ 4

Fig. 2 ARL experimental population of adhesive groups based upon Smax

and dfailure single-lap-joint performance at RT (dry conditioning) ........ 4

Fig. 3 Detailed ARL experimental population ofsingle-lap-joint performance 

showing adhesive chemical classifications. Dry sample conditioning 

tested at normal RT and humidity conditions (1.62-mm-thick 2024 

T3 aluminum substrates)....................................................................... 5

Fig. 4 The bonding requirements for adhesives in ground vehicle applications 

require technological development past aviation benchmarks ............. 8

Fig. B-1 The “S-curve” ..................................................................................... 11

Fig. C-1 The “S-curve” for aerospace adhesives .............................................. 16
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Coatings, Corrosion, and Engineered Polymers Branch

Standard Process Description (SPD)

Adhesives: Test Method and Group Assignment Guide for High-LoadingRate Applications – Preparation and Testing of Single-Lap-Joints

ARL-ADHES-QA-001.02 rev 1.0

Origin Date: 07/21/2008 Rev. No. 0.1 Date: 04/20/2017

Prepared by:

Robert Jensen

Experimental data by:

David Flanagan and Daniel DeSchepper

Adhesives and Informatics Team

Coatings, Corrosion, and Engineered Polymers Branch

Materials and Manufacturing Science Division

US Army Research Laboratory

RDRL-WMM-C

APG, MD 21005

Send comments or inquiries to: usarmy.APG.arl.mbx.adhesive-research@mail.mil

Reviewed by:

CCEPB ISO 9001:2008 Working Group

Charles Pergantis

Coatings, Corrosion, and Engineered Polymers Branch

Materials and Manufacturing Science Division

US Army Research Laboratory

RDRL-WMM-C

APG, MD 21005

Approved by:

James F Snyder (Chief)

Coatings, Corrosion, and Engineered Polymers Branch

Materials and Manufacturing Science Division

US Army Research Laboratory

RDRL-WMM-C

APG, MD 21005

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1.0 Purpose

This report provides the development history and rationale for the standard process 

description (SPD) ARL-ADHES-QA-001.00 Rev 1.0, Adhesives: Test Method, 

Group Assignment, and Categorization Guide for High-Loading-Rate 

Applications, by the Adhesives and Informatics Team, Coatings, Corrosion and

Engineered Polymers Branch (CCEPB), US Army Research Laboratory (ARL).

2.0 Scope 

This SPD fulfills partial requirements for the CCEPB to qualify for International 

Organization for Standardization 9001:2008 certification.

Disclaimer: This report contains ARL-originated studies containing advice and 

recommendations. The “History and Rationale” of the title is included as a 

consideration to future researchers.

Figure 1 shows the property assignment regions for adhesive group categories 

specified in Adhesives: Test Method, Group Assignment, and Categorization Guide 

for High-Loading-Rate Applications, ARL-ADHES-QA-001.00 Rev 1.0.1 The 

assignment regions can be defined by a plot of maximum strength (Smax) versus 

displacement complete failure (dfailure) as measured from standardized single-lapjoint tests per ASTM D1002 under quasi-static loading conditions at room 

temperature (RT).2 Figure 2 shows a global plot of Smax versus dfailure with the 

inclusion of 894 experimental data test points taken at and by ARL for various 

adhesive materials. Figure 3 provides a more-detailed data representation with 

respect to the adhesive material types. The intended ARL focus of testing these 

adhesives has primarily been for bonding armor assemblies. The global response to 

ballistic loading for a number of these adhesives has been observed and evaluated 

by ARL researchers.
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Fig. 1 Adhesive groups based upon single-lap-joint performance (Smax and dfailure) at RT

(dry conditioning)

Fig. 2 ARL experimental population of adhesive groups based upon Smax and dfailure singlelap-joint performance at RT (dry conditioning)

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

40.0

45.0

0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00

Maximum Strength (

Smax) (MPa)

Displacement at Complete Failure (dfailure) (mm)

Group I

Smax ≥ 10.0 MPa

dfailure > 3.81 mm

Group III

Smax ≥ 10.0 MPa

dfailure < 1.60 mm

Group II

Smax ≥ 10.0 MPa

1.60 mm ≤ dfailure ≤ 3.81 mm

Group IV

Smax < 10.0 MPa

0

5

10

15

20

25

30

35

40

45

0 1 2 3 4 5 6 7

Maximum Strength (

Smax) (MPa)

Displacement at Complete Failure (dfailure) (mm)

Group I

Smax ≥ 10.0 MPa

dfailure > 3.81 mm

Group III Group II

Group IV
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Fig. 3 Detailed ARL experimental population of single-lap-joint performance showing 

adhesive chemical classifications. Dry sample conditioning tested at normal RT and humidity 

conditions (1.62-mm-thick 2024 T3 aluminum substrates).

2.1 Adhesive Categories

2.1.1 Group I Category Adhesives (Adhesives for High-Loading-Rate 

Environments)

Group I adhesives represent a performance region where increases in ballistic 

damage tolerance occur with respect to survivability of the bondline. This is a 

qualitative assessment based on the global performance of the bonded armor 

assembly against the test threat, the size of the damage area, the damage modes of 

the constituent armor materials, and if the adhesive bondline will withstand 

multiple impacts (i.e., the strike face and backing plate bond remains intact). The 

further hot/wet and elevated temperature requirements specified in ARL-ADHESQA-001.00 are screening checks to minimize potential longer-term service 

durability issues with an upfront minimal effort in testing. ARL-ADHES-QA001.00 conveys the empirical observations and experience of ARL researchers in 

using adhesives to bond armor assemblies in terms of quasi-static performance 

metrics using a well-established academic and industrial test geometry 

configuration. The eventual “goal” for adhesives for armor applications is to 

develop, test, and evaluate a system able to withstand maximum strength and 

deflection much greater than 10.0 MPa and 3.81 mm, respectively, as shown in 

Fig. 3.
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2.1.1.1 Experimental and Modelling Challenges

The loading conditions experienced by ground combat vehicles during high-strainrate/high-stress (ballistic) events are complex.3–13 From the Army’s call for 

proposals to establish a Collaborative Research Alliance focused on Materials in 

Extreme Dynamic Environments (MEDEs), the fundamental problem is “the lack 

of understanding of the physical phenomena at multiple scales that govern highstress and high strain-rate material performance resulting from the paucity of 

validated linkages between experimental and computational research tools at 

critical length and time scales.”14 Specifically, the MEDE proposal guidance 

outlined the following major gaps in the current state of the art:

• A limited ability to relate materials chemistry, structure, and defects to 

materials response and failure under extreme conditions.

• An inadequate ability to predict the roles of materials structure, processing, 

and properties on performance in relevant extreme environments and 

designs.

• The lack of experimental capabilities to quantify multiscale response and 

failure of materials under extreme conditions.

2.1.1.2 Variable High-Loading-Rate Environments

Lightweight armor configurations are constantly evolving as new threats are 

encountered.15–21 Co-evolution of predator and prey species occurs in nature.

22–28

Historically, threat and protection schemes engaged in human combat are also 

continuously co-evolving, such as armor and antiarmor development. Liddel Hart 

pointed out that in 1940 the use of a propelled armored offensive was “a concept as 

revolutionary as the use of the horse, the long spear, the phalanx, the flexible legion, 

the ‘oblique order’, the horse-archer, the longbow, the musket, the [artillery] 

gun”.

29

2.1.1.3 Minimal Linkages to Academia and Industry

Little information pertaining to armor configurations exists in the open literature. 

Literature that does exist is related to generic (unclassified) armor configurations 

matched against unclassified threats, such as 7.62-mm fragment-simulating 

projectiles and so on. Typically, only the global response of the armor 

package/assembly is observed and evaluated. Regardless of the material studied 

(ceramic, metal, composite, adhesive, etc.), trends are implied, but distinct 

constitutive properties are seldom determined,

30–32 whereas useful generic studies 

are challenging to scale as the momentum and impact energies of the ballistic event 

increase in magnitude.
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Armor specifications are typically based upon performance, while aerospace 

adhesive specifications define precise material properties using standardized and 

accepted testing protocols. Aerospace specifications are well-known and 

implementable by adhesive formulators. Armor specifications, including spall 

liners, aluminum, and rolled homogeneous armor steel, are restrictive in terms of 

material composition and performance.33–36

The absence of high loading rate–derived adhesive specifications can lead to 

borrowing from aviation, which may not provide adequate performance in highloading-rate regimes.

2.1.1.4 Comments on Ballistic Testing of Adhesively Bonded Armor 

Assemblies

Judgments on the performance ratings of individual armor assembly constituents, 

including the adhesive, are typically tied to the global performance of the entire 

armor package. A high-performance rating from ballistic testing does not guarantee 

that the adhesive will maintain the characteristics as the threat and armor 

configuration vary. Likewise, poor performance in a single test configuration does 

not always guarantee that the adhesive will not be suitable in alternative armor 

designs.

2.1.2 Group II, III, and IV Category Adhesives

The experimental data points plotted in Figs. 1–3 show the highest population 

densities in Groups II, III, and IV. Groups II and III are attainable by current 

aerospace-grade bonding adhesives, and Group IV performance metrics can be 

achieved by aerospace-grade sealants. Groups II, III, and IV are realistic 

performance criteria for adhesives that have previously scaled through Department 

of Defense (DOD) technology-readiness-level progressions into full commercial 

availability. In contrast, Group I is sparingly populated with very few experimental 

data test points for a relatively few adhesives that are not at commercial acceptance 

levels. The continual evolving and variable nature of armor protection schemes will 

ensure a multitude of adhesive bonding schemes needed to meet Group I 

requirements. This armor configuration variability and relatively mild upperservice temperature requirements could provide the impetus for adhesive 

formulators to probe ground vehicle applications for product expansion, 

particularly where non-DOD commercial opportunities exist. This could potentially 

lead to adhesive advancements past the development plateau of aerospace, as 

portrayed in Fig. 4.
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Fig. 4 The bonding requirements for adhesives in ground vehicle applications require 

technological development past aviation benchmarks

Supplemental commentary is reported in the following appendix sections 

describing technological growth progression and a brief history of highperformance adhesives from the aerospace industry.

3.0 Policy

Not applicable.

4.0 Responsibilities

Not applicable.

5.0 Requirements

Not applicable.

6.0 Terms and Definitions

Not applicable.

7.0 Records

Not applicable.

Time

Growth

Aerospace

Ground Vehicle
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8.0 Appendix A. Innovation vs. Invention

Knowledge translation progresses through 3 stages: discovery, invention, and 

innovation.

37,38 Discovery is the identification of new knowledge and is 

traditionally brought into light through mechanisms such as peer-reviewed 

academic papers. The invention is the embodiment, or working demonstration, of 

the discovery into practice. Innovation is the refinement of the invention to a 

sufficient stage of development to bring it to the commercial market.

Joseph Schumpeter (1883–1950) adapted the phrase “Creative Destruction” in his 

theories of economic development.39–41 The variant phrase “Disruptive 

Technology”, by Joseph Bower and Clayton Christensen, gained popularity in the 

mid-1990s.42 However, Schumpeter’s economic theories remain influential to 

modern scholars.43

A transistor is a semiconductor device used to control and amplify electrical 

currents and is a model example contrasting the following invention versus 

innovation stages of technology development.

• The invention of the transistor was credited to John Bardeen, Walter 

Brattain, and William Shockley while working for Bell Telephone 

Laboratories in 1947. Efforts to invent a practical transistor were the 

accumulation of intense war-driven needs for enhanced radar performance. 

Bardeen, Brattain, and Shockley were awarded the 1956 Nobel Prize in 

Physics for their invention.44

• While the invention of the transistor in 1947 represented a tremendous 

scientific advancement, there were still many practical considerations that 

were yet to be developed to successfully transition the technology into 

commercial industry.45–48

• Gordon K Teal represents the “innovator” in the history of transistor 

technology. Teal was a former Bell Labs employee who began working for 

Texas Instruments in 1953. Teal overcame the performance limitations of 

Bell Labs’ germanium-based transistor design by developing a method to 

grow large single-crystal silicon as the semiconductor material. Texas 

Instruments was capable of mass producing the new silicon transistor 

design for the first successful transistor radio to progress beyond the 

prototype stage, the Regency TR-1, in 1954.

Innovation is the successful implementation of creative ideas within an 

organization.49 According to Joseph F Engelberger, the “father of robotics”, 

innovation requires 1) recognized need, 2) competent people with relevant 

technology, and 3) financial support.
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Innovation also carries very high failure rates. Failure leads to loss in morale, 

increased cynicism, and resistance to change. Erik Brynjolfsson (Massachusetts 

Institute of Technology’s Sloan School) basically states that industrial use of newer 

innovative technology occurs at higher levels once the existing management 

infrastructure exits the workforce.50,51
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9.0 Appendix B. Technological Development Curves

While Schumpeter provided the initial concept that innovation was the driving force 

for economic growth, it was W Rupert Maclaurin, Department of Economics and 

Social Science at the Massachusetts Institute of Technology in the 1940s and 1950s,

who first provided an analytically quantitative “linear model of innovation”.52 Prior 

to the Second World War, traditional economic theory reasoned that growth was 

simply related to the ability to increase available production capacity. Maclaurin 

systematically and rigorously studied “technological progressiveness” for a broad 

range of industries, including chemical, photographic, aviation, oil, radio and 

television, electric light, automobile, paper, steel, food processing, cotton and 

textiles, coal mining, and housing assembly, and derived the following “series of 

measurements” to track technological innovation for his linear model: “Linear 

model of innovation: Pure science to Invention to Innovation to Finance to

Acceptance”.

52

Many nonlinear recursive models have been proposed since Maclaurin’s initial 

linear growth theory to meet the complexities of specific industries.53

The “S-curve”, shown in Fig. B-1, was conceived in the early 1970s by Richard 

Foster while working as a business consultant for McKinsey and Co. in New 

York.54–56 The primary advantage of the S-curve is that it represents a model, of 

growth versus time, that is easy to comprehend.54,57

Fig. B-1 The “S-curve”

Some of the advantages of the S-curve include the following:

• Ease in evaluation of the different stages of technology

• Indicator of the need to shift when gains in growth decline

• Provides motivation to be at the forefront of new technology Growth

Time
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• Reduces the chances of hasty rejections of emerging technology

Some of the disadvantages of the S-curve include the following:

• Does not indicate how large the gains generated by the emerging 

technology will be

• Does not precisely guide business managers with respect to the timing of 

transitioning the shift from old to new technology

• The S-curve is a generalization, which may or may not fit to specific 

industries.

Research efforts to mathematically quantify the S-curve are ongoing, 

continually.

58–61

The actual invention stage and process of a technological growth curve, while 

significant, is a relatively small factor in determining the success of a new product.

Inventors who more fully understand the broader growth process of technology and 

who are more willing to escort their invention through licensing and potential 

commercialization in an advisory role seem to have a better chance at bridging the 

gap between invention and innovation.62 Braunerhjelm and Svensson62 verified 

Schumpeter’s assertion that the invention and innovation stages of technology 

growth are separate through a statistical study of Swedish patents. It was found that 

the success rate of the invention was actually lower if the inventor also assumed 

ownership and leadership during the innovation stage. However, true entrepreneurs 

who drive the innovation stage clearly benefitted when the inventor was able to 

assist in a supportive role, primarily to adapt the technology to specific customer 

needs and to reduce uncertainty.

Philibert provides a comprehensive approach to understanding the complexities in 

the relationships between invention, innovation, and the eventual diffusion of the 

new technology into the commercial marketplace at the international level in efforts 

to reduce global CO2 emissions.63 It seems to be clearly understood that the 

invention of new technologies as alternative energy sources is only a partial 

solution to curbing the rise of atmospheric CO2 levels.

It is also known that research and development managers at corporate and 

government levels are intimately connected with the success or failure of new 

inventions.64–66 Specifically, government lead research is in a position to absorb a 

greater amount of risk than corporate counterparts. Government-sponsored 

technical standards can provide motivation for private companies to progress from 

the invention to innovation stages.65 However, it is also cautioned that governmentsponsored technical standards that “do not endure” can also impede innovation.65
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10.0 Appendix C. Development History of Aviation Adhesives

10.1 Norman de Bruyne and Aero Research Ltd

Aviation material property requirements are dominated by “strength and stiffness”, 

which have been well-defined for the commercial adhesive industry since the 

middle of the 20th century:

• Aviation is a very mature industry, and the correlations between materials 

properties with processing, performance, design, structure, and 

manufacturing that have been studied extensively.67

• Modern adhesives with properties specifically tailored for aircraft 

fabrication were patented in Great Britain in the 1930s and in the United 

States in the 1950s.68–70

• Literature sources related to the performance of aircraft adhesives date at 

least to 1943.71

Modern aviation adhesives (and composites) owe their existence to the pioneering 

work of Norman Adrian de Bruyne in the 1930s through the 1950s.72–74 De Bruyne 

earned his master’s and doctoral degrees from Trinity College at the University of 

Cambridge studying electrical and radioactive field emission. De Bruyne had a 

passion for aviation and obtained his pilot’s license in 1929. “He was totally 

dissatisfied with the complacency shown in aircraft design during the late 1920s 

and early 1930s, and was convinced he could do a lot better.”72

De Bruyne formed The Cambridge Aeroplane Construction Company in 1931, 

which became Aero Research Limited (Duxford, Cambridge) in 1934. Aero 

Research Ltd was responsible for most of the initial ground-breaking inventions 

that aviation adhesives and composites were founded on, including the following:

• Invented Gordon Aerolite composite, which used a phenol-formaldehyde 

matrix and flax roving reinforcement.

• Invented Aerolite urea-formaldehyde adhesives for laminating and 

bonding wood. This adhesive was used to construct the laminated plywood 

Airspeed Horsa glider and de Havilland Mosquito.

• Invented sandwich honeycomb composite structures.

• Invented poly(vinyl formal) – phenol-formaldehyde adhesive (Redux 775) 

for the first metal-to-metal bonding in aircraft (de Havilland Sea Hornet).

• Invented modern film adhesives.
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• Educated and introduced a much broader commercial audience to the 

benefits of adhesive bonding through teaching annual “summer schools” 

at Cambridge University in the postwar years.

De Bruyne and the technical staff at Aero Research Ltd were also innovators. While 

phenol and urea-formaldehyde chemistry dates to the early 1900s,75,76 it was Aero 

Research Ltd that modified the chemistries and processing techniques that 

innovated their use for aviation applications.

10.2 Maturation of Redux 775

The advances in aviation adhesives pioneered by Norman de Bruyne and Aero 

Research Ltd in the 1930s and adopted by de Havilland in the 1940s were possible 

because the engineering properties required were already known.

From Kinloch’s memoir of de Bruyne:

• “De Bruyne became convinced that there was considerable scope for the 

introduction of novel designs and materials in aircraft structures, especially 

because it seemed that anything other than a biplane was regarded as 

un-English and not really practicable by the current aircraft design 

engineers.” 72

• De Bruyne set about designing and constructing the Snark73 in the early 

1930s.

• De Bruyne was able to construct the Snark as a monoplane using 

lightweight stressed plywood, laminated with phenol-formaldehyde resin, 

as the fuselage and wing material.

• The design was so advanced that the Royal Aircraft Establishment (RAE) 

initially “dismissed the whole design concept and stated that it could not 

issue a certificate (so the aircraft could be legally flown) for such a 

lightweight structure, because its light weight must imply an inadequate 

strength”.

• The Snark design was approved by the RAE on June 21, 1934, following 

full-scale destructive testing of the fuselage structure.

• Kinloch states that de Bruyne based his design of the Snark on “Prager’s 

analysis of plastic failure”77 and “Wagner’s tension field analysis”.78

The lessons learned from the Snark subsequently led de Havilland to use Aerolite 

urea-formaldehyde plywood bonding in the Mosquito73 poly(vinyl formal) –

phenol-formaldehyde adhesive (Redux 775) metal-to-metal bonding in the Sea 

Hornet73 and the transition of adhesive bonding into commercial aviation with the 
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Dove.79 By the end of the Second World War the basic correlations between 

fundamental quasi-static adhesive mechanical properties and the full structural 

response of aircraft were known, and the connection between performance 

requirements and formulation had essentially been bridged.

Although Aero Research Ltd was acquired by Ciba in 1947, Redux-type adhesives 

are currently qualified for aircraft production and sold through Hexcel.80

10.3 Increased Service Temperature Requirements

The need for higher service temperatures was a primary factor in driving adhesives 

for aviation applications beyond the initial phenol-formaldehyde base chemistry 

established by Aero Research Ltd. However, their exact histories are much more 

difficult to trace through academic literature and patent references. Wikipedia states 

that resin formulation based upon epichlorohydrin was first reported in 1927, and 

modern bisphenol-A epoxy resins were invented by Pierre Castan (Switzerland) 

and Sylvan Greenlee (United States) in 1937.81 The Wikipedia statements were not 

verified directly, though patents for Castan82 and Greenlee83 issued at later dates 

indicate that it is possible that they were involved with epoxy synthesis.

Likewise, the origins of epoxy film adhesives are equally obscure in the literature 

and patent archives, although Higgins reports the use of American Cyanamid 

(Cytec) FM 1000 for bonding in the Boeing 727 in 1963.84 A large number of 

representative epoxy adhesive patents can be found from the 1950s, 1960s, and 

1970s.85–87

The possible origins of bismaleimide (BMI) and cyanate-ester-resin-based 

adhesives are even more obscure in the patent literature.88,89 The academic literature 

for BMI and cyanate-ester-based adhesives becomes more widespread in the 1990s 

although not approaching the number of publications for epoxy adhesives.90,91

10.4 Plateaued Development

The drive by the commercial aviation industry for lighter aircraft has resulted in a 

steady increase the use of composite structures since the mid-1970s.84 The use of 

adhesives and composites should scale with each other.

• The McDonnell Douglass MD-80 used less than 5% composite structure 

by weight in 1980. The current Boeing 787 uses approximately 50% 

composite structure by weight.

• Additional metal-to-metal bonding also exists in aircraft, such as bonded 

reinforcement joints and struts, so the percentage of adhesive bonds used 

probably scales greater than the percentage of composite used.
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This increasing use of adhesives in aircraft since the 1970s is based upon chemistry 

that in some cases is decades old and has not translated to the continual 

development of new adhesive formulations or chemistries. Results from a market 

survey of the adhesives and sealants industries in 2008 revealed the following:

• The market survey reported profiles for 434 adhesive companies.

• The corporate trends seemed to point toward expanding production in the

BRIC (Brazil, Russia, India, and China) nations.

• Adhesive industry corporate news was dominated by mergers and 

acquisitions. The market survey acknowledged that the adhesives market 

is very dynamic.

• For 2008, 255 recent product innovations/introductions were listed but 

only one was aerospace-related: “Huntsman Advanced Materials Unveils 

New Aerospace Adhesives”.

• New developments in solvent-free and environmentally friendly adhesive 

technology appears as most prevalent product innovation.92

By 2008 the technological development of aviation adhesives were certainly well 

within the upper plateau of growth potential based on a simple S-curve analysis, as 

shown in Fig. C-1.

Fig. C-1 The “S-curve” for aerospace adhesives

Time

Growth

Aerospace
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11.0 Acknowledgments

Further contributions to the information contained in this SPD are included in the 

references.93–97

The authors also acknowledge Mr John Bishopp for historical support. He began 

his career at Aero Research Ltd and was very gracious in providing historical 

documentation for the usage of aircraft adhesives by England during the Second 

World War and the subsequent development of Redux 775.
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12.0 References

1. Jensen R, DeSchepper D, Flanagan D, Kosik-Chaney W, Robinette J, Chaney 

G, Pergantis C. Adhesives: test method, group assignment, and categorization 

guide for high-loading-rate applications. Aberdeen Proving Ground (MD): 

Army Research Laboratory (US); 2014 June. Report No.: ARL-SR-288.

2. ASTM standard D1002-10. Standard test method for apparent shear strength 

of single-lap-joint adhesively bonded metal specimens by tension loading 

(metal-to-metal). West Conshohocken (PA): ASTM International; 2010.

3. Woodward RL, Gooch WA, O’Donnell RG, Perciballi WJ, Baxter BJ, Pattie 

SD. A study of fragmentation in the ballistic impact of ceramics. International 

Journal of Impact Engineering. 1994;16:605–618.

4. Chin ESC. Army focused research team on functionally graded armor 

composites. Materials Science and Engineering. 1999;A259:155–161.

5. Lundberg P, Renstrom R, Lundberg B. Impact of metallic projectiles on 

ceramic targets: transition between interface defeat and penetration. 

International Journal of Impact Engineering. 2000;24:259–275.

6. Madhu V, Ramanjaneyulua K, Bhat TB, Gupta NK. An experimental study of 

penetration resistance of ceramic armour subjected to projectile impact. 

International Journal of Impact Engineering. 2005;32:337–350.

7. Savio SG, Ramanjaneyulua K, Madhu V, Bhat TB. An experimental study on 

ballistic performance of boron carbide tiles. International Journal of Impact 

Engineering. 2011;38:535–541.

8. Gupta N, Prasad VVB, Madhu V, Basu Bikramjit. Ballistic studies on TiB2-

Ti functionally graded armor ceramics. Defence Science Journal.

2012;62:382–389.

9. Deka LJ, Bartus SD, Vaidya U.K. Multi-site impact response of S2-

glass/epoxy composite laminates. Composites Science and Technology. 2009;

69:725–735.

10. Tasdemirci A, Hall IW. Numerical and experimental studies of damage 

generation in multi-layer composite materials at high strain rates. International 

Journal of Impact Engineering. 2007;34:189–204.

11. Bartus SD, Vaidy UK. A review: impact damage of composite materials. 

Journal of Advanced Materials. 2007;39:3–21.
ARL-ADHES-QA-001.02 Rev 1.0

Approved for public release; distribution is unlimited.

19

12. Resnyansky AD. The impact response of composite materials involved in 

helicopter vulnerability assessment: literature review – part 1. Edinburgh 

(South Australia): Defence Science and Technology Organisation; 2006. 

DSTO Report No.: DSTO-TR-1842 Part 1. 

13. Resnyansky AD. The impact response of composite materials involved in 

helicopter vulnerability assessment: literature review – part 2. Edinburgh 

(South Australia): Defence Science and Technology Organisation; 2006. 

Report No.: DSTO-TR-1842 Part 2. 

14. Collaborative Research Alliance (CRA) for Materials in Extreme Dynamic 

Environments (MEDE). Funding opportunity title announced by the US Army 

Research Laboratory [accessed 2011]. http://www.arl.arm.mil/www/pages

/532/FINAL_MEDE_PA.pdf.

15. Deka LJ, Bartus SD, Vaidya UK. Multi-site impact response of S2-glass/epoxy 

composite laminates. Composites Science and Technology. 2009;69:725–735.

16. Deka LJ, Bartus SD, Vaidya UK. Damage evolution and energy absorption of 

e-glass/polypropylene laminates subjected to ballistic impact. Journal of 

Materials Science. 2008;43(13):4399–4410.

17. Bartus SD. A review: impact damage of composite materials. Journal of 

Advanced Materials. 2007;39(3):3–21.

18. Bogetti TA, Hoppel CPR, Harik VM, Newill JF, Burns BP. Predicting the 

nonlinear response and failure of composite laminates: correlation with 

experimental results. Composites Science and Technology. 2004;64:477–485.

19. STANAG 4569. Procedures for evaluating the protection level of logistic and 

light armoured vehicles. Brussels (Belgium): North Atlantic Treaty 

Organization; 2012.

20. Wikipedia. STANAG 4569 [accessed 2012 Jan 24]. http://en.wikipedia.org

/wiki/STANAG_4569.

21. Purchase description transparent armor. Warren (MI): US Army TankAutomotive and Armaments Command; 26 Apr 2010. Report No.: Metric 

ATPD 2352R.

22. ISI Web of Knowledge. Keyword search “predator and prey and evolution”.

2488 references, 199 since September 2012 [accessed 2013 Sep 5].

https://webofknowledge.com.

23. Mougi A, Iwasa Y. Unique coevolutionary dynamics in a predator–prey 

system. Journal of Theoretical Biology. 2011;277:83–89.
ARL-ADHES-QA-001.02 Rev 1.0

Approved for public release; distribution is unlimited.

20

24. Lin G. Spreading speeds of a Lotka–Volterra predator–prey system: the role 

of the predator. Nonlinear Analysis. 2011;74:2448–2461.

25. Ellner SP, Becks L. Rapid prey evolution and the dynamics of two-predator 

food webs. Journal of Theoretical Ecology. 2011;4:133–152.

26. Reynolds C. Interactive evolution of camouflage. Artificial Life. 2011;17:123–

136.

27. Zylberberg J, DeWeese MR. How should prey animals respond to uncertain 

threats? Frontiers in Computational Neuroscience. 2011;5:1–7.

28. He Q, Mobilia M, Tauber UC. Coexistence in the two-dimensional MayLeonard model with random rates. The European Physical Journal B.

2011;82:97–105.

29. Manchester W. The last lion: Winston Spencer Churchill. Boston (MA): Little, 

Brown and Company; 1988. p. 672. Manchester cites Liddell-Hart BH. History 

of the Second World War. London (UK): Weidenfeld Nicholson; 1970. p. 66–

67.

30. Tasdemirci A, Tunusoglu G, Güden M. The effect of the interlayer on the 

ballistic performance of ceramic/composite armors: experimental and 

numerical study. International Journal of Impact Engineering. 2012;44:1–9.

31. Lopez-Puente J, Arias A, Zaera R, Navarro C. The effect of the thickness of 

the adhesive layer on the ballistic limit of ceramic/metal armours: an 

experimental and numerical study. International Journal of Impact 

Engineering. 2005;32:321–336.

32. Grujicic M, Pandurangan B, d’Entremont B. The role of adhesive in the 

ballistic/structural performance of ceramic/polymer–matrix composite hybrid 

armor. Materials and Design. 2012;41:380–393.

33. MIL-DTL-62474F w/amendment 1. Laminate: aramid-fabric-reinforced, 

plastic; 2008 May 21. Superseding MIL-DTL-62474F; 2007 Nov 29.

34. MIL-DTL-64154B w/amendment 1. Laminate: fiberglass-fabric-reinforced, 

phenolic; 19 2012 Jan 19. Superseding MIL-DTL-64154B; 2008 Dec 17.

35. MIL-DTL-46027K(MR). Armor plate, aluminum alloy, weldable 5083, 5456, 

and 5059; 2007 July 31. Superseding MIL-DTL-46027K(MR): 1998 Sep 4.
ARL-ADHES-QA-001.02 Rev 1.0

Approved for public release; distribution is unlimited.

21

36. MIL-DTL-12560J(MR). Armor plate, steel, wrought, homogeneous (for use in 

combat-vehicles and for ammunition testing); 2009 July 24. Superseding MILA-12560H(MR) w/amendment 4; 2007 July 20 and MIL-DTL-46177C(MR);

1998 Oct 24.

37. Lane JP, Flagg JL. Translating three states of knowledge – discovery, 

invention, and innovation. Implementation Science. 2010;5(9). 

38. Artz KW, Norman PM, Hatfield DE, Cardinal LB. A longitudinal study of the 

impact of R and D, patents, and product innovation on firm performance. 

Journal of Product Innovation Management. 2010;27:725–740.

39. Wikipedia. Joseph Schumpeter [accessed 2011 Dec 20]. http://en.wikipedia

.org/wiki/Joseph_Schumpeter.

40. McCraw TK. Prophet of innovation: Joseph Schumpeter and creative 

destruction. Cambridge (MA): Belknap Press of Harvard University Press;

2007.

41. Schumpeter JA. Business cycles: a theoretical, historical and statistical 

analysis of the capitalist process. Vol. 2. New York (NY): McGraw-Hill; 1939.

42. Boyer JL, Christensen CM. Disruptive technologies: catching the wave. 

Harvard Business Review. 1995;73(1):43–53.

43. Wonglimpiyarat J. The nano-revolution of Schumpeter’s Kondratieff cycle. 

Technovation. 2005;25:1349–1354.

44. Nobelprize.org. The Nobel Prize in Physics 1956 [accessed 2011 Dec 22]. 

http://www.nobelprize.org/nobel_prizes/physics/laureates/1956/.

45. Riordan M. The lost history of the transistor. IEEE Spectrum. 2004;41(5):44–

49.

46. Riordan M. The end of AT & T. IEEE Spectrum. 2005;42(7):46–51.

47. Riordan M. How Europe missed the transistor. IEEE Spectrum.

2005;42(11):52–57.

48. Riordan M. How Bell Labs missed the microchip. IEEE Spectrum.

2006;43(12):36–41.

49. Wikipedia. Innovation [accessed 2011 Dec 20]. http://en.wikipedia.org/wiki

/Innovation.

50. Brynjolfsson E. TED.com [accessed 2014 June 4]. https://www.ted.com

/talks/erik_brynjolfsson_the_key_to_growth_race_em_with_em_the_machines.
ARL-ADHES-QA-001.02 Rev 1.0

Approved for public release; distribution is unlimited.

22

51. Brynjolfsson E, McAfee A. Winning the race with ever-smarter machines. 

MIT Sloan Management Review. 2012;53(2):51–60.

52. Godin B. In the shadow of Schumpeter: S Rupert Maclaurin and the study of 

technological innovation. Minerva. 2008;46:343–360.

53. Schmoch U. Double-boom cycles and the comeback of science-push and 

market-pull. Research Policy. 2007;36:1000–1015.

54. Asthana P. Jumping the technology s-curve. IEEE Spectrum. 1995;32(6):49–

54.

55. Foster R, Kaplan S. Creative destruction: why companies that are built to last 

under-perform the market – and how to successfully transform them. New 

York (NY): Doubleday; 2001.

56. Foster R. Working the s-curve – assessing technological threats. Research 

Management. 1986;29(4):17–20.

57. 12Manage. S-Curve [accessed 2011 Dec 22]. http://www.12manage.com

/description_s_curve.html.

58. Bonser RHC, Vincent JFV. Technology trajectories, innovation, and the 

growth of biomimetics. Journal of Mechanical Engineering Science Part C. 

2007;221:1177–1180.

59. Sood A, Tellis GJ. Technological evolution and radical innovation. Journal of 

Marketing. 2005;69(7):152–168.

60. Nikula U, Jurvanen C, Gotel, O, Gause DC. Empirical validation of the classic 

change curve on a software technology change project. Information and 

Software Technology. 2010;52:680–696.

61. Bejan A, Lorente S. The constructal law origin of the logistics s curve. Journal 

of Applied Physics. 2011;110:024901.

62. Braunerhjelm P, Svensson R. The inventor’s role: was Schumpeter right?

Journal of Evolutionary Economics. 2010;20:413–444.

63. Philibert C. Technology innovation, development and diffusion. Paris 

(France): Organisation for Economic Co-operation and Development (OECD) 

and International Energy Agency (IEA); 2003.

64. Schilling MA, Esmundo M. Technology s-curves in renewable energy 

alternatives: analysis and implications for industry and government. Energy 

Policy. 2009;37:1767–1781.
ARL-ADHES-QA-001.02 Rev 1.0

Approved for public release; distribution is unlimited.

23

65. Cozzarin BP. Performance measures for the socio-economic impact of 

government spending on R and D. Scientometrics. 2006;68(1):41–71.

66. Yang K-P, Chiao Y-C, Kuo C-C. The relationship between R and D investment 

and firm profitability under a three-stage sigmoid curve model: evidence from 

an emerging economy. IEEE Transactions on Engineering Management.

2010;57(1):103–117.

67. Miller AG, Lovell DT, Seferis JC. The evolution of an aerospace material: 

influence of design, manufacturing and in-service performance. Composite 

Structures. 1994;27(1–2):193–206.

68. De Bruyne NA, Rayner CAA. Improvements in or relating to synthetic resin 

adhesives or cements. British patent 540,442; 1941 Oct 17. 

69. De Bruyne NA, Newell GS, Perry KRC, inventors; Ciba Ltd, assignee. Selfsustaining adhesive sheet and process for producing the same as well as for 

uniting surfaces with it. United States patent US 2,872,365. 1959 Feb 3.

70. De Bruyne NA, inventor. Rohm & Haas, assignee. Method of providing 

adhesion between surfaces. United States patent US 2,499,134. 1950 Feb 28.

71. Dietz AGH, Grinsfelder H. Behavior of plywood under repeated stresses 

Transactions of the ASME. 1943;65:187–191.

72. Kinloch AJ. Norman Adrian de Bruyne, 8 November 1904 – 7 March 1997. 

Biographical Memoirs of Fellows of the Royal Society. 2000;46:125–143.

73. Bishopp JA. The history of redux and the redux bonding process. International 

Journal of Adhesion and Adhesives. 1997;17:287–301.

74. Cognard P, editor. Handbook of adhesives and sealants. Chapter 5, vol. 1: 

adhesives and sealants: basic concepts and high tech bonding. San Diego (CA): 

Elsevier; 2005.

75. Baekeland LH, inventor. Baekeland LH, assignee. Method of making insoluble 

products of phenol and formaldehyde. United States patent US 942,699. 1909

Dec 7.

76. Ripper K, inventor. Process for manufacturing homogeneous glasslike 

condensation products of urea and formaldehyde. United States patent US 

1,625,283. 1927 Apr 19.

77. Prager W. The influence of distortion on the theorem of plastic bodies.

Zeitschrift fur Anqewandte Mathematik und Mechanik. 1935;15:76–80.
ARL-ADHES-QA-001.02 Rev 1.0

Approved for public release; distribution is unlimited.

24

78. Wagner H. Flat sheet metal girders with very thin webs, part I – general 

theories and assumptions. Washington (DC): National Advisory Committee 

for Aeronautics; 1931. Technical Memorandum No. 604.

79. The Aeroplane. 1946 Sep 20; No: 329. 

80. Adhesives - the redux range of film adhesives, foaming films, primers and 

liquid shims [accessed 2016 Dec 6]. http://www.hexcel.com/products

/aerospace/aadhesives-main.

81. Wikipedia. Epoxy [accessed 2012 Jan 01]. http://en.wikipedia.org/wiki/Epoxy

_adhesive#Adhesives.

82. Castan P, inventor. Process of preparing synthetic resins. United States patent 

2,324,483. 1943 July 20.

83. Greenlee SO, inventor, Devoe & Raynolds Co., assignee. Amine-epoxyphenol compositions. United States patent 2,510,855. 1950 June 6.

84. Higgins A. Adhesive bonding of aircraft structures. International Journal of 

Adhesion and Adhesives. 2000;20:367–376.

85. Been JL, Grover MM, inventors, Rubber and Asbestos Corporation, assignee. 

Adhesive compositions of polyepoxide resins and butadiene-acrylonitrile 

rubbers and method of making bristle brushes using same. United States patent

US 2,879,252. 1959 Mar 24.

86. Olsen MM, inventor, assigned to Minnesota Mining and Manufacturing 

Company (3M), assignee. Adhesive-coated sheet material. United States 

patent US 3,326,741. 1967 June 20.

87. Batzer H, Lohse F, Schmid R, inventors. Ciba Ltd., assignee. Curable epoxy 

resin composition containing novel disecondary amines. United States patent 

US 3,609,121 1971 Sep 28.

88. Angelo RJ, Tatum WE, inventors, E.I. du Pont de Nemoirs and Company, 

assignee. Aromatic polyamide-amides. United States patent US 3,316,212;

1967 Apr 25.

89. Loudas BL, Vogel HA, inventors, Minnesota Mining and Manufacturing 

Company (3M), assigne. Cyanatophenyl-terminated polyarylene ethers.

United States patent US 3,595,900. 1971 July 27.

90. Chin JW, Wightman JP. Surface characterization and adhesive bonding of 

toughened bismaleimide composites. Composites Part A. 1996;27A:419–428.
ARL-ADHES-QA-001.02 Rev 1.0

Approved for public release; distribution is unlimited.

25

91. Kinloch AJ, Taylor AC. The toughening of cyanate-ester polymers. part 1 -

physical modification using particles, fibres and woven-mates. Journal of 

Materials Science. 2002;37:433–460.

92. MarketResearch.com. Adhesives and sealants. San Jose (CA): Global Industry 

Analysts, Inc; 2008 Mar 1.

93. Jensen R, Kosik W, Gardner J, O’Brien D. Critical adhesive needs for Army 

applications and opportunities for innovation. Presented at the 34th Annual 

Meeting of the Adhesion Society; 2011 Feb 13–16; Savannah, GA.

94. Kosik W, Squillacioti R, Ziegler W, Gardner J, Jensen R. Novel adhesives 

innovation through forward looking specifications requirements and database 

implementation. Presented at the 34th Annual Meeting of the Adhesion 

Society; 2011 Feb 13–16; Savannah, GA.

95. Jensen R, Kosik WC, DeSchepper D, Flanagan D. Leveraging Army unique 

mission requirements to advance the state-of-the-art in adhesives development.

Blacksburg (VA): Adhesion Society Newsletter; 2011 Dec.

96. Kosik WC, Kaufman J, DeSchepper D, Flanagan D. Curatorial protocols for 

capturing single-lap joint test results using the materials selection analysis tool 

platform. Presented at the 35th Annual Meeting of the Adhesion Society; 2012

Feb 26; New Orleans, LA.

97. Jensen R, Kaufman J, Kosik WC, Henrie B. Screening adhesively bonded 

single-lap-joint testing results using nonlinear calculation parameters.

Presented at the 35th Annual Meeting of the Adhesion Society; 2012 Feb 26; 

New Orleans, LA.
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List of Symbols, Abbreviations, and Acronyms

ARL US Army Research Laboratory

BMI bismaleimide

BRIC Brazil, Russia, India, and China

CCEPB Coatings, Corrosion and Engineered Polymers Branch

dfailure displacement complete failure

DOD Department of Defense

MEDEs Materials in Extreme Dynamic Environments

RAE Royal Aircraft Establishment

RT room temperature

Smax maximum strength

SPD standard process description
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