The process of making Vietnam plywood involves bonding together wood veneers with the use of glue, also known as resin. Glue plays a crucial role in the manufacturing of plywood as it is the key factor that determines the strength, quality, and longevity of the plywood panels. Therefore, it can be said that glue is an indispensable component of plywood. Depending on the intended use of the plywood, there are varies type of glue
In Vietnam plywood production, there are commonly three types of glue, including PF, MUF, and UF.
- Phenol Urea-formaldehyde (PUF)
- Melamine Urea-formaldehyde (MUF)
- Urea-formaldehyde (UF)
1.Phenol Urea-formaldehyde Glue – High price, High Bonding strength and endure for 72 hours of water boiling
The most expensive adhesive for plywood is the WBP Phenolic glue, which has a dark brown color and is commonly referred to as Exterior glue. The PUF thermosetting resin is a type of glue that is made by combining methylol phenol and urea under acidic conditions, resulting in improved bonding strength compared to other commercial resins. The PUF resin requires high-temperature curing to create a permanent bond that can withstand various environmental conditions, making it ideal for use in exterior plywood, structural plywood, film faced plywood and Flooring Base Plywood.
Producing plywood with phenolic glue is a task not possible for every plywood factory, owing to the nature of the adhesive. A crucial aspect that must be strictly kept in mind during the process are two factors.
a) A high-pressure hot press machine is a necessity.
b) The production must be well-timing between each process due to the PF glue’s quick drying
The benefits of phenolic glue include its exceptional bonding strength, resistance to water and high temperatures, chemical stability, as well as being resistant to fungi and termites.
The drawbacks of phenolic glue include its brittle glue layer, the need for high temperature and pressure during production, and difficulty in controlling production due to the quick drying time of the glue.
2.Melamine Urea-formaldehyde (MUF) Glue – Medium price, provide medium bonding strength and 4- 24 hours water boiling proof (depending on the percent of Melamine ratio)
Melamine UF glue is a combination of melamine, urea, and formaldehyde that is modified with melamine and PVA for use in producing E0 plywood in plywood factories.
The quality of the MUF glue is dependent on the ratio of urea and melamine, with melamine typically weighing between 5 to 20 percent of the urea weight. Too much melamine will drive up the cost, while too little melamine will result in weaker adhesive properties.
MUF is waterproof but will eventually deteriorate after prolonged exposure to weather. The process for MUF glue can be undertaken at room temperature or a higher temperature depending on the specific application and performance requirements. Generally, melamine adhesives perform well against water. Plywood with a MUF glue is ideal for limited weather exposure situations, such as exterior door skins, marine plywood, and concrete formwork. While melamine glue plywood can be employed in damp or wet settings, it cannot withstand long-term exposure to rain.
3.Urea-formaldehyde (UF) Glue – Low price, provide medium bonding strength and about 3 hours of water boiling
UF adhesives, which are cost-effective and thermosetting polymers, are commonly utilized for indoor purposes and are a result of the condensation reaction between urea and formaldehyde.
UF glue offers a fast curing time and has a broad operating range, making it a popular choice in the plywood industry, where 80% of the material is manufactured utilizing this glue. Melamine may be used to create MUF glue by modifying UF glue. UF glue is simple to manufacture and bonds well, but it is only meant for occasional dampness exposure and cannot be used in structural or wet regions. Blending urea-formaldehyde with soy protein concentrate can improve the performance of UF glue. If added in an appropriate proportion, it can enhance the plywood’s shear strength and formaldehyde emissions can be reduced.
At the Kim Gia Plywood Mill, we are flexible to produce with all the glue options,
For the Melamine Plywood, HPL Plywood and Birch Faced products, our commonly producing is MUF glue with Carb P2 standard, however, Phenolic glue are available as your request.
For the Floor-Based Plywood, to adapt the strength and Water resistance requirement requirements, the Phenolic glue is usually use, nonetheless MUF can also be interchange for lower standard requirements.
Please contact us for more consultant
Loc Luong
Export Sales Department
Mail: locluong.kggroup@gmail.com
WhatsApp’s No: 0902200987