1-800-220-1966
Monday - Friday 8:30AM - 5:00PM EST

ADHESIVES

We carry products from many manufacturers such as Devcon, Permatex, Lord, Permabond and Pacer Tech. These companies are pioneers and world leaders in bonding technologies providing us with an extensive array of industry standard products as well as special adhesives, with unique properties and capabilities to meet your most demanding applications.

DEFINITION OF ADHESIVES

Any substance, inorganic or organic, natural or synthetic, that is capable of bonding two objects together by surface attachment or adhesion.

TYPES OF ADHESION

MECHANICAL - Results when one surface is roughened and offers something for the adhesive to grab mechanically.
CHEMICAL - Reaction or attraction of the molecular forces between the adhesive and the surfaces to be bonded.

ADHESIVE ADVANTAGES

Ability to bond different materials to each other.
Attach thin and small parts with ease.
Equal distribution of stress not possible with screws.
High environmental resistance- heat, cold and the weather.
Non-electrically conductive
Less Weight
Fast, easy assembly
Reduced cost
Acts as a sealant and moisture barrier.

ADHESIVE DISADVANTAGES

Many adhesives require extended curing times to reach full bond strength.
Bonded components cannot be easily disassembled.
Parts may require design change for adhesive application.
Parts must mate well and provide bond area.
Adhesive may be attacked by some chemicals.
Most adhesives limited to temperatures below 400 F

MODERN ADHESIVE TECHNOLOGY

Adhesives have become an important part of modern industry. From the tiles on the Space Shuttle to bonding parts on many home appliances, they invade every area of our lives. Having some knowledge of what adhesives are and how to properly use them will be an asset to the technician as well as any handy person.


GENERAL INFORMATION ON USING ADHESIVES


WHAT CAN BE BONDED?

Nearly every material natural or synthetic may be bonded with adhesives. What adhesive to use for the best bond is directly related to the material. Some materials bond easily and others require special preparation to achieve a good bond.

POINTS TO CONSIDER WHEN SELECTING AN ADHESIVE

Substrate Materials - are they the same or different, porous or nonporous, rigid or flexible, plastic or metal?

Joint Design - is based on the type of stress the joint must be resisted. Types of joints are covered later in this section.

Gap Filling - is required when mating poorly fitting parts.

Environment - the temperature and moisture, chemical and shock resistance must be evaluated.

Handling Bond - the time for the adhesive to "set" or hold the assembly together must be considered.

Cure Time - the importance of the period of time required for the adhesive to reach its full strength.

Appearance - the color or clarity of the adhesive may affect the appearance of the product.

Cost - the quanity of adhesive, its packaging, shelf life and method of dispensing affect cost.

Preparation - is it a one or two part adhesive. If it is a two part adhesive, how difficult and critical is the mix ratio? Dispense Method - is relative to the adhesive used and the area to be covered. It may be manual, semi or fully automatic.

The selection of an adhesive for your application can be a complex matter of meeting many needs. Therefore, it is advisable to consult the manufacturer or adhesive distributor for technical

POINTS TO CONSIDER WHEN USING ADHESIVES

Storage Life - Adhesives do not last forever, therefore, do not buy in quanities greater than needed. The storage life of some adhesives may be extended by refrigeration at 40 F. Do not freeze. Storage life ranges from 6 months to a year - unopened.

Preparation - Other than selecting the the proper adhesive, preparing the substrate for bonding is of great importance. Surface contamination is the frequent cause of bond failure. When possible, clean the surfaces with a solvent or cleaner that will not leave a residue of any kind. Be sure the surface is dry. Roughen the surface to help the adhesive grab the material and wipe away any loose particles. Some materials require the application of a primer to improve bondability.

The Temperature Limits of most adhesives falls between - 40 F and 400 F. However, it is important to check each adhesive for its specific temperature range. There are special ceramic adhesives available for ultra high temperature applications to 4000 F. The ideal temperature for using an adhesive is 70 F. The lowest recomended temperature for using an adhesive is 55 F. In general, raising the temperature of many adhesives will shortened their working life. Keep in mind that the working time given by the manufacturer is normally 70 F and a summertime temperature of 95 F may reduce the open, set, and cure times of the adhesive.

Electrical Conductability - most adhesives are good insulators, however, there are some available that are made into conductors for special applications by the use of silver fillers.

The Chemical and Environmental Resistance of most adhesives is very good. One of the most common elements that an adhesive must resist is moisture, humidity and water. Check with the manufacturer for this kind of resistance. The adhesive industry does not usually give a chelnical resistance chart for its adhesives, but each user must do his own testing to arrive at the suitability of an adhesive for each application.

How Adhesives Cure should be understood by the user. In two part adhesives a chemical cure is created by mixing the resin with the hardner or accelerator. Single part, moisture cure adhesives react to surface moisture or the humidity of the surrounding air. Other solvent or water based adhesives cure with evaporation. Anaerobic adhesives cure in the absence of air. Actural full cure or reaching full strength is a chemical process that varies with each type of adhesive. Setting, or the initial grabbing of the adhesive is only the beginning of the curing process and the assembly should not be subjected to stress or test until the time of full cure has passed. guidance.


UNDERSTANDING JOINTS AND STRESS


The basic types of adhesive joints and loading forces are illustrated on the two following pages.



The simple lap joint. On loading, the adhesive and the adherend react to the applied forces. There is a shear force along the plane of the joint and a peel force at right angles to it. These stresses are at a maximum at the edges of the bond where they cause high levels of strain and twisting as illustrated in the drawing.


Basic bonded joints between sheetmetal. In practical structures two or more basic types may be used in combination, and the relative dimensions of the joints may vary from those shown.


ADHESIVE SELECTION GUIDE





Code:        A= strongest bonds
                   B= Good bonds - with limitations
                   C= Non-structural bonds
                   D= Poor bonds - not recommended
                  @= Special treatment required * Includes UV adhesives


ADHESIVE CHARACTERISTICS

ACRYLICS - Fast, strongest bonds on metals and plastics.
EPOXIES - Strong bonds on most substrates.
URETHANES - Strength with flexibility.
CYANOACRYLATES - Speed & Strength with limitations
ANAEROBICS - Metal sealing and locking
EMULSION - Strong bonds on porous substrates.
CONTACT - Quick grab, non-structual bonds.
HOT MELTS - Fast,non-structural bonds on most materials.
SEALANTS - Flexible joint sealing.

ADHESIVE DISPENSING SYSTEMS


MANUAL APPLICATION METHODS

BRUSH - Available in various sizes, a brush offers the simplest method of applying adhesive when limited control is required.

TROWEL - Specially designed for spreading adhesives evenly on broad surfaces.

ROLLERS - (paint type) For fast application of adhesive on large areas.

SQUEEZE BOTTLES - (with nozzles) For limited application of small amounts of adhesive.

CARTRIDGE GUNS - (air/manual) For applying a bead of single part adhesives.

DUAL PACK CARTRIDGES - Deliver two part adhesives through a static mixing nozzle. Eliminates the need to hand mix and the problem of achieving proper mix ratios.

SYRINGES - (air/manual) For applying small amounts of low viscosity adhesives.

VALVES - (auto./manual) Available with nozzles for multiple heads and tips for special applications.

SPRAY VALVES - For fast coating of large areas with sprayable adhesive.

The applicator to use will depend on the type of adhesive, the amount to be applied, the area to cover, difficulty of application and production requirements.

AUTOMATIC AND SEMI-AUTOMATIC SYSTEMS

Automatic adhesive dispensing systems are used when precise control of the amount and placement of adhesive is required. Fully automatic systems are completely "hands off" operations and range from simple trigger mechanical control to complex electronic and computerized robotic systems. Semi-automatic systems indicate some manual function involved in the cycle of operation.

SEMI-AUTOMATIC SYSTEMS - offer a considerable increase in efficiency at moderate cost over manual systems.

MANUAL ACTUATION involves foot pedal or push button control of application cycle.

MANUAL PLACEMENT - nozzle or substrate manipulated for application of adhesive.

FULLY AUTOMATIC SYSTEMS though expensive, provide precise control of all operations thereby reducing labor costs, improving quality control, and reducing waste.

ACTUATION - adhesive application automatically dispenses the correct amount, in timed intervals, at the right location.

PLACEMENT - substrate is automatically positioned for proper placement of adhesive.


ADHESIVE DISPENSING EQUIPMENT


MICRO AIR DISPENSING

Electro-Pneumatic controllers for dispensing solder masks, sealants, lubricants, epoxies, cyanos, or solvents. These units are used for precision application of small amounts of product usually through syringes.

PRESSURE TANKS

When moderate quanitities and pressures are needed in a dispensing system pressure tanks are ideal. Available in steel and stainless steel and in one gallon or larger sizes.

AIR POWERED RECIPROCATING PUMPS

These pumps are required when high pressure and volume are needed to supply large production adhesive systems. Pumps are available in stainless steel for long service life.

DISPENSING NOZZLES

Nozzles or tips provide for precise application of an adhesive. Beading, roller, spray, cleat and needle are a few of the standard nozzles. Custom tips can be designed to meet special applications.

MANUAL AND AIR POWERED GUNS

Compact, lightweight, air powered or manual guns for field applications are available for one or two component materials. Most guns are adaptable to various size cartridges.

DIAPHRAGM PUMPS

Stainless steel diaphragm pumps are high volume, self prining material suppliers for any fluid system. A well designed pump will provide stall free, low maintenance operation for adhesive systems

METER & MIX SYSTEMS

Complete systems designed to automatically dispense one, two or more component materials.

AUTOMATIC DISPENSING VALVES

These valves are the heart of any automatic adhesive system, providing the precision metering necessary for most operations.

CONTROL SYSTEMS

Electronic and pneumatic control systems including logic packages, timers, sensors, limit switches and actuators provide for the ultimate in design for any production need.



EMULSION ADHESIVES (WHITE GLUES)


EMULSION ADHESIVES are water dispersions of small particles of high strength adhesive materials such as polyvinyl acetate polymers, copolymers and resins. The bond is formed by the absorption of water by the substrates. This adhesive is primarily used or porous materials such as wood and wood products. However, other combinations of materials may be bonded, such as plastics and metals, as long as one surface will absorb water. Though very strong, these adhesives should not be used in high stress post forming.

USING EMULSIONS:

Except with tightly fitting parts, joints should be clamped during the setting period which is about 30 minutes and full cure or strength develops in 24 hours. Adhesive may be applied to only one surface. Various formulations of this adhesive are available for industrial use other than the general purpose products found in retail stores. Emulsions are not gap filling and should be used only on well fitting tight joints. Joints are water resistant but not water proof.

SELECT EMULSIONS for quick setting strong joints on wood and other porous materials.


CERAMIC ADHESIVES


Adhesives with a thermoplastic base are usually limited to temperatures below 350 o F. Adhesives with a ceramic base raise this limit to over 5000 o F. These adhesives are comparable in strength to epoxies and acrylics. and are available in many different formulations for various applications.

APPLICATIONS:

Adhesive bonds ceramics, glass, metals, graphite and other high temperature materials. Use for ovens, burners, electrical sealing, potting and any application requiring high temperature resistance. Consider the difference in expansion rates between different materials when bonding for high temperatures.


SPECIAL ADHESIVES


PRESSURE SENSITIVE ADHESIVES are applied to a surface and permitted to dry. That surface will then adhere to most other materials on contact with pressure. Bonds may be temporary or permanent. These adhesives are usually made from natural or synthetic rubber.

SELF-SEAL OR COHESIVE (COLD SEAL) LATEX ADHESIVES - an adhesive that will adhere only to itself. Bond strength is variable and may be permanent or resealable. May be used as a protective coating that will not transfer to the material being coated.

HEAT SEAL ADHESIVES are waterborne resin heat seal adhesives. Heat seals are applied to one surface and dried. Adhesive is then activited for bonding by applying heat. Temperatures required vary from 175 0 to 300 0 F depending on adhesive.
FUGITIVE ADHESIVES form a temporary bond between two materials. The two materials may then be separated without damaging either surface. Made from natural rubber latex, it has no tack, dries clear, and is non-staining.

NON-FRAY ADHESIVES are used to prevent fabrics from unraveling or to give fabrics a firmer feel. These adhesives are high gloss, water resistant, and clear when dry.


ADHESIVE BONDING TERMINOLOGY


The following list of technical terms will help in understanding the adhesive bonding process..

ADHESION: The state of two surfaces held together by interfacial forces, to be stuck or clinging together..

ADHESIVE: A substance that holds or bonds together two surfaces by mechanical or chemical forces..

AMBIENT TEMPERATURE: The temperature surrounding or in the room where an object rests..

BLEED-THROUGH: The migration of an adhesive through a surface so that it becomes visible..

BOND: The attachment of an adhesive to a surface or surfaces..

BOND STRENGTH: The force or load that can be applied to a bonded joint before it will fail or break..

CATALYST: A substance added in small amounts to an adhesive to speed up the cure time..

CEMENT: Another word for adhesive..

COHESION: The state in which the particles of the adhesive are held together..

COHESIVE FAILURE: A term used to describe bond failure within the glue line without failure of either bonded surface. COLD FLOW: Dimensional change of a material under load at room temperature. Also known as Creep..

CONTACT ADHESIVE: An adhesive which when coated on two surfaces for bonding, when dried will adhere only to itself. May be solvent or waterborne..

COVERAGE: The amount of adhesive required to cover a specific square foot area for proper bonding..

CRAZING: The creation of fine cracks or dull haze in substrates caused by solvent or adhesive compounds attacking the surface. The effect may also appear in the adhesive..

CREEP: A change in size of a material under load. Movement at room temperature is often called creep..

CROSS LINKING: The union of two large molecules by means of chemical reaction resulting in a random network of molecules which no longer have mobility..

CURE: The change in physical property of an adhesive caused by a chemical reaction which may be by condensation, polymerization or vulcanization. Usually produced by the action of heat and a catalyst alone or in combination with or without pressure. In common terms it is the process in which an adhesive dries or changes to bond two substrates together.

CURE TEMPERATURE: Ideal temperature for maximum cure to take place for a specific adhesive.

DELAMINATION: The separation of layers of a laminate do to failure within the adhesive itself or the bond between the adhesive and the substrate.

DRY:
ion, The change in state of an adhesive by loss of evaporatabsorption or both.
.
ELASTOMER: A material which, at room temperature, can be stretched repeatedly beyond its original size and when released return to its former size. (Rubber)

EMULSION: A suspension of particles of liquid or solid in a normally incompatible liquid.

FATIGUE: The internal weakening of a dried or cured adhesive resulting from constant static or dynamic force acting on it.

FLASH POINT: The temperature at which the vapors of an adhesive or other chemical will ignite when exposed to an open flame.

GREEN STRENGTH: The amount of strength in an adhesive before achieving full curing or drying.

HARDENER: Added to an adhesive to promote or control curing. See Catalyst.

LATEX: A very fine particle size emulsion.

NON-STRUCTURAL BOND: A bond that is required to bear little or no load other than to hold two parts together.

OPEN TIME: The time between the application of an adhesive to a surface and assembly of the two parts.

POT LIFE: The period of time during which a adhesive may be used satisfactorily after being mixed or exposed to drying air.

SHELF LIFE: (Same as storage life) The period in which an adhesive may be stored in its original unopened container at a specific temperature and still be usable.

SUBSTRATE: The material surface to which an adhesive is to be spread for bonding.

TACK:
The stickiness or ability of an adhesive to cling to an object.

THERMOPLASTIC: A material that will repeatedly soften when heated and harden when cooled.

THERMOSET: A material that after being exposed to heat will remain in a fixed or infusible state.

THIXOTROPIC: A property in which a chemical's viscosity will lessen after being agitated such as in stiring or pumping.

VISCOSITY: The thickness or heaviness of a liquid and its resistance to flow such as the difference between a 10 weight oil and a 40 weight oil.

WETTING: The ability of an adhesive to adhere to a surface immediately upon contact.


Items 1 to 9 of 4190 total

per page
Page:
  1. 1
  2. 2
  3. 3
  4. 4
  5. 5

Set Descending Direction