This report is one of a series issued in cooperation with Air Force-Navy-Civil Subcommittee on Aircraft Design Criteria under the supervision of the Aircraft Committee of the Munitions Board. Revised April 1954. Addendum added. Supplement available with revisions. No. 1842A
This report is one of a series issued in cooperation with the ANC-23 Panel on Sandwich Construction of the Departments of the Air Force, Navy, and Commerce.
This report is one of a series issued in cooperation with the Air Force-Navy-Civil Subcommittee on Aircraft Design Criteria under the supervision of the Aircraft Committee of the Munitions Board.
This report is one of a series issued in cooperation with the ANC-23 Panel on Sandwich Construction of the Departments of the Air Force, Navy, and Commerce.
This report is one of a series issued in cooperation with Air Force-Navy-Civil Subcommittee on Aircraft Design Criteria under the supervision of the Aircraft Committee of the Munitions Board.
This report is one of a series issued in cooperation with the ANC-23 Panel on Composite Construction for Flight Vehicles of the Departments of the Air Force, Navy, and Commerce.
This report is one of a series issued in cooperation with the Air Force-Navy-Civil Subcommittee on Aircraft Design Criteria under the supervision of the Aircraft Committee of the Munitions Board. Information reviewed and reaffirmed March 1956 and 1962. Original report issued December 1950.
This report is one of a series issued in cooperation with the ANC-23 Panel on Sandwich Construction of the Departments of the Air Force, Navy, and Commerce. Information reviewed and reaffirmed 1960. Original report dated August 1955.
The quality and cost of wood particle composites are substantially
determined by how the adhesive that bonds the composite is
distributed on the particles. Distribution of the adhesive is controlled
by the method of application. Currently the adhesive is applied by
spraying it onto the particles. It was hypothesized that...
Bonding kinetics of thermosetting adhesives plays an important role
within wood based composites during hot pressing, and in determining
appropriate processing schedules for the manufacture of composites. A
dynamic method has been developed to offer a direct means for
investigating physical transformations that occur during bond
formation, and the influence...
The importance of wood bonding increased in the last decades due to the
increased usage of wood composites whose performance depends to a large extent on
the adhesive penetration and subsequent bonding of the adherends. The presented
research used XMT (x-ray microtomography) to perform a non-destructive, threedimensional
analysis of the...
Wood adhesives are essential components of wood composites. At
present, the commonly used wood adhesives, phenol-formaldehyde (PF)
and urea-formaldehyde (UF) resins, are petroleum-based synthetic resins
that may result in emission of formaldehyde in the production and use of
wood composites. Because the world's oil reserves are naturally limited
and formaldehyde...
Cross-laminated timber (CLT) is a massive engineered wood product made of orthogonally bonded layers of solid-sawn lumber, and is intended for roof, floor, or wall applications. Although it was developed in Europe in the early 90s, CLT is relatively new to North America.
CLT products must be certified for structural...
Moisture durability is essential for wood composites, especially those used in building construction, where products are prone to weathering. The primary focus of this research was to determine if adhesive penetration into the cell wall has a positive influence on adhesive bond durability. To fully understand the measureable effects of...
There is no doubt that adhesive penetration plays an important role in wood bondline joint performance and durability; yet, to date there is no direct experimental evidence linking penetration depth with bond performance. This is, in part, because adhesive penetration is commonly assessed with various 2D microscopy techniques that are...
Presently, the production of wood composites relies on the formaldehyde-based wood adhesives such as phenol-formaldehyde (PF) and urea-formaldehyde (UF). However, their dependence on exhaustible fossil fuels and the emission of carcinogenic formaldehyde prompt to develop an environmentally friendly adhesive from renewable natural resources. This work focuses on development and characterization...
Formaldehyde-based adhesives such as urea-formaldehyde (UF), phenol-formaldehyde (PF) are widely applied in wood-based composite industry. However, these adhesives are all petrochemical-based and could not sustain in a long term due to a limited reserve of oil and natural gas. Moreover, these adhesives emit carcinogenic formaldehyde in the production or use...
Particleboard is widely used for making bookshelf, furniture, cabinets and many other interior products. At present, particleboard is mainly produced with wood particles and urea-formaldehyde (UF) resins. The emission of carcinogenic formaldehyde in the production and use of particleboard has generated an urgent need for development of a formaldehyde-free wood...
Due to its importance, the phenomenon of hydrogen
bonding has been the subject of much research over the
years. Among the different techniques used to study
hydrogen bonded systems, vibrational spectroscopy is
perhaps the most sensitive because of the striking
changes induced in molecular spectra by the formation of
hydrogen...
The use of adhesives in demanding engineering applications is a very common
occurrence in the modern world. These adhesives are taking the role of many traditional
fasteners, especially in the area of fiber reinforced composites. As the use of these
adhesives become more common place, better understanding of their mechanics...
Natural fibers are gaining popularity as reinforcement materials for thermoset resins over the last two decades. Natural fibers are inexpensive, abundant, renewable and environmentally friendly. Kenaf fibers are one of the natural fibers that can potentially be used for reinforcing unsaturated polyester (UPE). As a polymer matrix, UPE enjoys a...
Formaldehyde-based adhesives such as urea-formaldehyde (UF) and phenol-formaldehyde (PF) adhesives dominate the current wood adhesive market. However, these adhesives are derived from petrochemicals and carcinogenic formaldehyde. In this study, we developed two formaldehyde-free adhesives based on abundant, renewable, and inexpensive soy flour (SF).
The first adhesive was mainly composed of...
Synthetic adhesives like phenol formaldehyde (PF) and isocyanates dominate the
wood based structural panel market. The raw materials that makeup these adhesives
are based on petroleum and natural gas. The sustainability and the continued success
of the wood based structural panel industry will benefit from the development of
alternative adhesives...
This report is one of a series issued in cooperation with Air Force-Navy-Civil Subcommittee on Aircraft Design Criteria under the supervision of the Aircraft Committee of the Munitions Board. Information reviewed and reaffirmed May 1954 and 1962. This report was originally published December 1949.
A low-temperature liquid-to-vapor counterflow microchannel heat exchanger has been redesigned and fabricated using a scalable, low-cost adhesive bonding process. Adhesive erosion concerns are mitigated with the use of sealing bosses. Performance has been tested using water and compressed air as test fluids. Results show greater effectiveness and higher heat transfer...
Synthetic adhesives, such as phenol-formaldehyde (PF) resins and urea-formaldehyde (UF) resins, have dominated the wood adhesive market since they were introduced in the wood products industry. Formaldehyde, as a key component in the manufacturing of PF and UF resins, has been classified as a known human carcinogen by the International...
It was the goal of this research to determine if sago
starch could be used to replace wheat flour as an adhesive
extender of Urea-formaldehyde plywood adhesives through
either chemical modification of the starch or modification
of the adhesive formulation strategy. Guiding principles of
the research would be that a...
A new adhesive bonding method is introduced for microlamination architectures, for producing low-temperature microchannel arrays in a wide variety of metals. Sheet metal embossing and chemical etching processes have been used to produce sealing bosses and flow features, resulting in approximately 50% fewer laminae over traditional methods. These lamina designs...
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Brian K. Paul
A new adhesivebonding method is introduced for microlamination architectures
Wood-based composites such as plywood and particleboard are produced with a thermoset adhesive via a hot-press process. At present, UF is the most commonly used thermoset adhesive for production of decorative plywood. The emission of the carcinogenic formaldehyde from UF-bonded panels during the use of panels affects the indoor air...
Existing pressure sensitive adhesives (PSAs) are mostly based on petrochemicals. In this study, a novel PSA based on a renewable material, methyl oleate, was prepared and characterized. Methyl oleate was first epoxidized to form epoxidized methyl oleate that was subsequently hydrolyzed and acidified to form epoxidized oleic acid (EOA) which...
This report is one of a series issued in cooperation with Air Force-Navy-Civil Subcommittee on Aircraft Design Criteria under the supervision of the Aircraft Committee of the Munitions Board. Information reviewed and reaffirmed October 1954.
Polyethylene has been used extensively for natural gas transport since the mid-1970's. The pipeline system is sound and well-functioning, but there are some aspects of the system that could be improved. One of these is the repair method of leaking pipes. Presently if a natural gas pipe begins to leak,...
Cross Laminated Timber (CLT) technology has been growing in the EU and Canada
since the early 1990's and utilizes the mechanical properties of structural grade
lumber to create a strong panel product for use in floor, ceiling and wall systems. The
hypothesis of this project was that CLT panels made...
As a new product patented by Freres Lumber Company in 2018, little information exists for manu-facturing procedures of mass plywood panels (MPP). At first glance, MPP may appear to be ply-wood, laminated veneer lumber (LVL), or similar to conventional cross-laminated timber (CLT). Often manufacturers, as well as users, of MPP...
Structural engineered wood manufacturers need a quantitative measurement technique to determine the ratio of wood to adhesive failure in their shear specimens. Visual estimation of percent wood failure has long stood as an extremely subjective quality control approach according to ASTM D5266 – Standard Practice for Estimating the Percentage of...
The dynamics of radio frequency (RF) laminated veneer lumber (LVL) pressing are explored for the purpose of optimizing this process. The RF LVL press at the Albany Trus Joist plant is the focus of this investigation. The investigation first focuses on bond strength development characteristics of the Georgia Pacific adhesive...
Thermal wave imaging (TWI), a technology based on heat conduction and radiation through materials, is a relatively new addition to current non-destructive inspections (NDI) systems. Bonding of composites, an extremely important step in manufacturing and repair of laminates, could be affected by defects originating from faulty manufacturing processes or damages...
There is no doubt that adhesive penetration plays an important role in wood bondline joint performance and durability; yet, to date there is no direct experimental evidence linking penetration depth with bond performance. This is, in part, because adhesive penetration is commonly assessed with various 2D microscopy techniques that are...
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, and throughout the
bonding process. Both iodine concentration and cured adhesive density were
The paper describes a Thermally-Enhanced Edge Registration (TEER) technique for precision aligning large numbers of laminae in diffusion bonding processes. This technique is particularly relevant for the formation of micro heat exchangers and microreactors requiring highly paralleled microchannel arrays but is also being used to register other laminated devices with...
The thermodynamic and structural effects of highly anisotropic, short-ranged attraction are investigated for single- and four-site interaction models using Wertheim's multi-density graph theory of chemical association. Both models consist of associating hard spheres, where the saturable attraction sites are described by conical wells centered in the hard core and evaluated...
This symposium was arranged and conducted in cooperation with the Research and Products Committee of the National Lumber Manufacturers Association, 1319 Eighteenth St., N.W., Washington 6, D.C. The purpose was to bring together a group of approximately 100 individuals broadly representing various phases of the wood industry, the present wood...
This paper reports the feasibility of using surface mount adhesives to produce low temperature microchannel arrays in a wide variety of metals. Sheet metal embossing and chemical etching processes have been used to produce sealing bosses that eliminate channel laminae, resulting in approximately 50% material savings over traditional methods. An...
Spraying of liquid adhesive onto wood surfaces has shown to be a highly effective and efficient method of application across many different wood-based composite industries. However, the dynamics of spraying are extremely variable and distribution can be affected by liquid properties (rheology, molecular weight distribution, and temperature), application parameters (disk...
Increased competition in the market place for both occasional and professional chain saw users has led to a desire for improved performance in chain saw guide bars. One aspect of improved performance is lower bar weight. The primary focus of this research was to establish the feasibility of a lower...
There have been many attempts to characterize and mimic natural fluid-based adhesive systems. However, very few of these studies have examined surface or interfacial interactions between adhesive and substrate. Furthermore, until now no study has used a combination of surface analytical and kinematic techniques to determine the precise chemical mechanisms...
The mechanical performance of composite materials is determined by the mechanical properties of their individual components and the effective load transfer between these components. Binders are commonly used to bond composite components together and to provide effective load transfer between them. In wood-based composites the binder-component load transfer occurs at...
Accelerated weathering (AW) tests have become a requirement for many wood composite products. This project monitored temperature and moisture content of specimens undergoing AW exposure for the following standards: ASTM D3434 (automatic boil test), CSA O112.9 (boil-dry-freeze), and PS2 (Section 7.17, 6-cycle VPS). Each AW procedure was conducted with three...
A phenol formaldehyde (PF) adhesive was uniformly tagged with iodine such that it yielded sufficient x-ray computed tomography (XCT) gray-scale contrast for material segmentation in reconstructed wood-composite bondlines. Typically, untagged adhesives are organic and have a similar solid state density as wood cell-walls, and therefore cannot be segmented quantitatively in...
As a result of its atomic structure, carbon fiber produced from mesophase pitch
has a high electrical conductivity and high tensile strength. Others have used carbon fiber
as a resistive heating unit to accelerate matrix solidification in carbon fiber-polymer
matrix composites.
In this study, a unidirectional carbon fiber reinforced polymer...
High-pressure torsion (HPT) is used to investigate the formation of a new metal system by the direct bonding of separate disks of Al and Cu by processing at room temperature under a compressive pressure of 6.0 GPa and with increasing numbers of HPT turns up to 60. A detailed examination...
Adhesive use is becoming increasingly common in manufacturing processes. The advantage of adhesives are light weight components, non-destructive fastening techniques and distribution of loads over the applied bond region. Modeling the behavior of adhesive bond lines in fastening joints can help in the design process to make an optimized joint,...
In wood-plastic composites (WPCs) a compatibilizer is often used to improve
the interfacial adhesion between the hydrophilic wood filler and the hydrophobic
plastic matrix. At present, while the basic concepts of compatibilization are
understood, the optimized chemical structures of an effective compatibilizer, including
the ideal structures of the wood-binding domain...
Transient liquid-phase diffusion brazing is used in precision, hermetic joining applications as a replacement for diffusion bonding to reduce cycle times, reduce bonding pressure and improve yields. Studies showed that the interlayer used in diffusion brazing can be detrimental due to the use of melting point depressants (MPDs). The goal...
This work is a culmination of a series of published works related to the use of the Material Point Method (MPM) in modeling wood adhesive bonds. The use of wood as construction material has the potential to play a small role in the solution to the current CO2 and climate...
This report is one of a series issued in cooperation with the Army-Navy-Civil Committee on Aircraft Design Criteria under the supervision of the Aeronautical Board.
This report is one of a series issued in cooperation with the ANC-23 Panel on Composite Construction for Flight Vehicles of the Departments of the Air Force, Navy, and Commerce. Information reviewed and reaffirmed 1962. Original report issued January 1956.
Microscale X-ray computed tomography (XCT) is discussed as a technique for identifying 3D adhesive distribution in wood-adhesive bondlines. Visualization and material segmentation of the adhesives from the surrounding cellular structures require sufficient gray-scale contrast in the reconstructed XCT data. Commercial wood-adhesive polymers have similar chemical characteristics and density to wood...
The mechanical performance of wood-based composites is determined by the mechanical properties of their individual components and the effective load transfer between these components. In laminated wood composites, this load transfer is facilitated by the adhesive bond. The experimental methodology developed in this study measures and analyzes the full-field deformation...
In this study, triglycidylamine (TGA) was synthesized and evaluated as a crosslinking agent for soy flour (SF) for making five-ply plywood from yellow poplar. Glycerol polyglycidyl ether (GPE) and trimethylolpropane triglycidyl ether (TTE) were also investigated as crosslinking agents for SF as adhesive for plywood. The plywood panels bonded with...
In the search to improve and incorporate nano and renewable materials into urea-formaldehyde (UF), several researchers have incorporated cellulose nano fibrillated (CNF) into the adhesive. This study aimed to find an optimal way of incorporating CNF into UF and understand how CNF interacts with and changes the properties of the...
Pacific shrimp (Pandalus jordani) was washed repeatedly and the
eluted bacteria were enumerated and identified. Selected isolates
were tested for their adhesive properties.
Washing reduced the microbial load by 3.84 to 42.04%. The bacteria
which most resisted wash-off were Staphylococcus and Pseudomonas
spp. The easiest to wash off was Flavobacterium...
Heating, ventilation, and air conditioning systems represent nearly half of building energy usage in the United States. Recent building regulations requiring increased air turnover within buildings will result in even greater air conditioning usage. To alleviate these concerns, membrane-based heat-and-moisture exchangers known as energy recovery ventilators have been developed to...
Efficient usage of resin is of critical importance to industry in the manufacture of wood composite panels, because resin represents a significant proportion of product costs. However, resin efficiency is poorly defined in literature, making it difficult to compare manufacturing processes in quantifiable terms. Additionally, resin content in the product...
Wood-plastic composites (WPCs) are one of the fastest-growing sectors of the
wood composites industry. However, the strengths of WPCs are typically low
because of the poor interfacial adhesion between hydrophilic wood and
hydrophobic thermoplastics. A compatibilizer that can form bridges between wood
and plastics is required to give WPCs desirable...
The advent of synthetic adhesives has transformed the structural applications of wood. However, a persistent issue in adhesively-bonded wood products has been moisture durability. When designing wood based composites, moisture durability will depend on both the wood phase and the adhesive phase. A key question, therefore, is how does one...
Wood composites are an important renewable structural material which can be a net carbon sink when used in combination with sustainable forest management practices and high rates of log utilization. Adhesive bondlines are an essential part of composites, and for wood composites, they determine the moisture durability and mechanical performance...
This report is one of a series issued in cooperation with the Army-Navy-Civil Committee on Aircraft Design Criteria under the supervision of the Aeronautical Board.
Abstract: Three novel curing agents ( I , II , and III) were synthesized
from epichlorohydrin and ammonium hydroxide.
The combinations of soy flour (SF) with one of the curing
agents (SF- I , SF- II , and SF- III ) were investigated as adhesives
for making interior plywood. Water...
Current lathe technology, smaller diameter logs, smaller core diameters, and
the sale of higher grade veneer for use in engineered wood products are all factors
contributing to plywood manufacturers using rougher veneer with different lathe
check characteristics. When rough veneer is encountered, plywood manufacturers
typically increase the adhesive spread rate...
The importance of wood bonding increased in the last decades due to the
increased usage of wood composites whose performance depends to a large extent on
the adhesive penetration and subsequent bonding of the adherends. The presented
research used XMT (x-ray microtomography) to perform a non-destructive, threedimensional
analysis of the...
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that adhesivebonding was begun in
about 1500 B.C. by the Egyptians, whereas others believe adhesive
The importance of wood bonding increased in the last decades due to the
increased usage of wood composites whose performance depends to a large extent on
the adhesive penetration and subsequent bonding of the adherends. The presented
research used XMT (x-ray microtomography) to perform a non-destructive, threedimensional
analysis of the...
In this paper we present a novel fabrication technique that utilizes polycaprolactone (PCL) as bonding media due to its low melting temperature property. PCL is biodegradable polyester with a melting point of 60°C, and a glass transition temperature of -60°C [1-10]. It is employed as a rapid bonding technique in...
