Things you should know about wood-based panels
How can you step up your process while and keep adhesive performance at a high level? How can you produce more cost-effective boards?
The quality of wood-based panels may vary depending on the manufacturing technology used. In this section, we discuss how you can bring particle board to the next level by improving your process and the efficiency of the adhesive.
Table of contents
1. What are wood based panels?
Wood-based panels refer to a variety of different board products made from wood in the form of chips, strips, veneers, strands or fibres. Examples of wood-based panels are particle board, fibre board, plywood and oriented strand board (OSB).
2. How do you manufacture particle board?
Particle board is manufactured by compressing wood chips with an adhesive. In most cases, the adhesive consists of urea formaldehyde, or melamine urea formaldehyde resin with a hardener such as ammonium sulfate or ammonium nitrate.
Application of the adhesive to the wood chips can be done by different methods:
- Pre-mixing: the resin and the hardener are mixed in the same tank before being sprayed on the wood chips.
- Inline mixing: the resin and the hardener are held in separate tanks and premixed shortly before being sprayed on the wood chips.
- Separate spraying: the resin and the hardener are in different tanks and are separately sprayed on the wood chip.
Exilva MFC
Exilva is a microfibrillated cellulose that can improve adhesive strength, sustainability, and manufacturing cost.
3. How can you improve your process?
The main advantage of the first two methods is the superior quality of the adhesive. The resin and hardener are homogeneously mixed before being sprayed onto the chips, securing good bonding. The drawback to these methods is that premature reaction can occur between the resin and hardener causing build-up in the production streams and resulting in downtime.
Separate spraying allows for better production conditions as it eliminates the potential for unwanted build-up of the adhesive. However, the resultant quality of the adhesive is poorer than that of the two first methods, as mixing of the resin and hardener is not optimal.
With all three methods of application of the adhesive (pre-mixing, inline mixing, separate spraying), Exilva has shown advantages when it is introduced to the adhesive system.
Exilva® as a rheology additive enables better spraying due to its strong shear thinning behaviour. Owing to its high viscosity at rest, it modifies the wetting of the wood chips by preventing the adhesive system from penetrating too quickly into the wood chip. A better distribution of the adhesive system, as well as better mixing between the resin and the hardener are therefore, achieved securing good bonding.
4. How can you produce better performing panels?
One of the most important properties of particle board is the internal bond or tensile strength. This is a measure of the maximum strength the board can withstand before it breaks.
Regardless of the manufacturing technology, Exilva can improve the performance of your glue by increasing the internal bond of the board.
Indeed, thanks to its unique fibrils network characterised by a large surface area and high crystallinity, the cellulose fibrils act as a reinforcement aid.
The unique rheology properties of Exilva provide better coverage of the wooden substrate contributing to improved bond strength.
Therefore, Exilva provides the opportunity to reduce the amount of resin per cubic meter of board resulting in lower cost and potentially lower formaldehyde content and emissions of the board.
5. In a nutshell, how can Exilva help you?
Exilva provides an opportunity to:
- Enhance the efficiency of board manufacture
- Reduce resin content by increasing the efficiency of the adhesive
- Improve the sustainability of the adhesive as less petroleum-derived resin is required
- Reduce manufacturing costs