What is adhesive? What are the main physical properties and testing standards of adhesives?

What is adhesive?

The use of adhesives is used in all aspects of life and production, such as adhesives for electronic components, adhesives for automotive interior parts, adhesives for packaging materials, surface bonding of shoe materials and other construction or decorative materials; then what are adhesives? What are the main physical properties and testing standards of adhesives?
Adhesion (bonding, bonding, gluing, gluing) refers to the technology in which the surfaces of homogenous or dissimilar objects are joined together with an adhesive, which has the characteristics of continuous stress distribution, light weight, or sealing, and low temperature for most processes. Adhesive bonding is especially suitable for the connection of different materials, different thicknesses, ultra-thin specifications and complex components.
A class of natural or synthetic, organic or inorganic substances that can connect two or more parts or materials through interfacial adhesion and cohesion, collectively referred to as adhesives, also known as adhesives , customarily referred to as glue. In short, an adhesive is a substance that binds the adherends together through adhesion. “Adhesive” is a generic standard term.

Main physical properties of adhesive

  1. Operation time
    Maximum time interval between adhesive mixing and pairing of parts to be bonded
  2. Initial curing time
    Time to Removable Strength Allows Adequate Strength for Handling Bonds, including Moving Parts from Fixtures
  3. Complete curing time
    Time required to achieve final mechanical properties after adhesive mixing
  4. Storage period
    Under certain conditions, the adhesive can still maintain its handling properties and the storage time of the specified strength
  5. Bonding strength
    Under the action of external force, the stress required to make the interface between the adhesive and the adherend in the adhesive part break down or its vicinity
  6. Shear strength
    Shear strength refers to the shear force that the unit bonding surface can withstand when the bonding part is damaged, and its unit is expressed in MPa (N/mm2)
  7. Uneven pull-off strength
    The maximum load that the joint can bear when subjected to uneven pull-off force, because the load is mostly concentrated on two edges or one edge of the adhesive layer, and the force is per unit length rather than per unit area, and the unit is KN/m
  8. Tensile strength
    Tensile strength, also known as uniform pull-off strength and positive tensile strength, refers to the tensile force per unit area when the adhesive is damaged by force, and the unit is expressed in MPa (N/mm2).
  9. Peel strength
    Peel strength is the maximum load per unit width that can withstand when the bonded parts are separated under the specified peeling conditions, and its unit is expressed in KN/m

Common test items for adhesives

  1. Physical properties
    General properties: thickness; viscosity; water resistance
    Mechanical Testing: Tensile Properties; Peel Strength; Tensile Shear Strength; Compressive Shear Strength; Horizontal and Vertical Tack
    Burning performance: horizontal burning; vertical burning; glow wire burning
    Electrical properties: surface and volume resistivity of insulating materials; surface resistivity of anti-static materials; dielectric strength, breakdown voltage; withstand voltage
  2. Aging test
    Rapid UV aging; xenon lamp aging; temperature and humidity aging; salt spray aging; appearance and performance evaluation after aging
  3. Component analysis
    Principal component qualitative analysis; full component qualitative analysis; full component quantitative analysis; ash content
  4. Reliability
    Temperature and humidity cycle; temperature shock; waterproof and dustproof; vibration test

Current relevant standards for adhesives

  1. GB 18581-2009 Limits of Hazardous Substances in Solvent-Based Wood Coatings for Interior Decoration Materials
  2. GB/T 2791-1995 Adhesive T peel strength test method flexible material to flexible material
  3. GB/T 27934.3-2011 Process control and testing methods for lamination of paper printed matter
  4. GB/T 2794-2013 Determination of Adhesive Viscosity Single Cylinder Rotational Viscometer Method
  5. GB/T 16585-1996 Vulcanized rubber artificial weathering (fluorescent ultraviolet lamp) test method
  6. GB/T 7124-2008 Adhesive Shear Strength
  7. ASTM D 1781-1998 Adhesive Roller Peel Test Method

Adhesives are widely used in various fields of the national economy and have become indispensable for the development of the national economy due to their advantages of realizing the connection of the same or dissimilar materials, no stress concentration at the joint, high bonding strength, and easy to realize automatic chemical operation. chemical products.

What is the above ie adhesive? What are the main physical properties and testing standards of adhesives? For more information about adhesives, log in to the Thermal Adhesives Network (www.coolthermo.com) to inquire!

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