What is the primary use of adhesives specified in IS 4835?

They are primarily used for woodworking, joinery, furniture assembly, and bonding other lignocellulosic materials.

What is the acceptable pH range for PVA wood adhesives?

The pH should generally be between 4.0 and 6.0 to prevent staining of the wood while ensuring the chemical stability of the adhesive.

How is the adhesive strength tested?

It is tested by determining the dry state joint strength of bonded standard wood specimens using a universal testing machine as per Appendix A.

IS 4835

: 1979

Specification Polyvinyl Acetate Dispersion-Based Adhesives for Wood

CurrentSpecializedSpecificationMaterials Science · Wood and Other Lignocellulosic Products

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This standard prescribes the requirements, methods of sampling, and tests for polyvinyl acetate (PVA) dispersion-based adhesives intended for general woodworking, joinery, and allied applications.

Specification Polyvinyl Acetate Dispersion-Based Adhesives for Wood

Quick Reference Values

Minimum non-volatile content40 percent by mass

pH range4.0 to 6.0

Moisture content of wood for testing12 ± 2 percent

Practical Notes

PVA adhesives covered by this standard are typically meant for interior use and may not perform well under continuous exposure to moisture or wet conditions.

Wood substrates should be properly planed, dust-free, and dry (ideal moisture content 10-14%) prior to adhesive application to achieve optimal bond strength.

Protect the adhesive from freezing temperatures during storage, as freezing can permanently break the emulsion/dispersion.