Wood adhesive for use at very low temperatures

Cold winter temperatures can cause problems for woodworkers. Not only finishing suffers but also other operations, one of which is gluing. A wood glue formulated specifically for cold weather can only make it easier for those in the industry, but not only for them. As we are in the middle of the cold season I think that presenting such an adhesive for winter is helpful.

Problems encountered during the freezing winters prompted adhesive manufacturer Szolvegy to find solutions to help its customers. 

It is about Tiszabond 3011/D3D of the Szolvegy Târgu Mureș. The adhesive is a company project developed specifically for partners who face very cold winter temperatures. Matefy Csaba, the director of the company, told me that one of his customers, located in Miercurea Ciuc, often faced problems due to the very cold winters in the region. We have all heard that Miercurea Ciuc is considered to be the pole of cold in our country. Almost every winter, the lowest temperatures are recorded there, some of them even record low. In these conditions they had difficulties to maintain in the hall temperatures of 18-20 grd.C, as required by the technical data sheets of adhesives, and in unheated warehouses the temperature easily reached below 0°C.

That's how a winter glue came into being that makes film even at 0°C.

To solve these problems, an adhesive has been developed that works even after one, two or even three freeze-thaw cycles. Mr Matefy says this is the advantage of working directly with the manufacturer, of direct contact between the furniture manufacturer and the adhesive manufacturer. It creates a strong partnership because information flows faster and easier and this enables the adhesive manufacturer to create the best and most suitable products for the furniture and wood panel manufacturer. That was the case here. Customer requirements led to an adhesive Tiszabond for winter.

The new wood glue is a D3 glue and one of the advantages of using it is the lack of formaldehyde.

The adhesive is a polyvinyl acetate in aqueous dispersion. Unlike ureo-formaldehyde adhesives, they do not contain formaldehydewhich makes the panels and furniture free of free formaldehyde emissions due to the adhesive. Aqueous polyvinyl acetate dispersions are not harmful to the user or the environment. In short, in this respect their advantages are:

• lack of formaldehyde
• are not flammable
• does not harm health
• dry residues are not hazardous waste

Tiszabond winter adhesive is a D3 adhesive. This means that it can be used for interior construction exposed to short-term moisture or damp environments, for exterior construction in mild climates, for joining steps, doors or windows installed in weather-protected areas. However, it is not recommended for structures and objects that stand continuously in the water (boats, ships) or for structural strength in construction (beams supporting the roof).

Compared to other D3 adhesives this Tiszabond winter adhesive has a number of properties that eliminate problems that can occur when temperatures are very low.

Here are some of them:

• Even if frozen, the adhesive can be used after thawing. It just needs to be shaken very well. After freezing, the viscosity of the product may increase slightly. It is recommended to use it undiluted in order not to decrease the solid content and not to prolong the drying time. If undiluted use is not possible, a dilution of maximum 10% is acceptable. After repeated freeze-thaw cycles the product turns into a gel and can no longer be used.
• The film formed is less hard which leads to improved flexibility of the bonded elements. Also the decrease in the hardness of the film results in a lower aggression on the lamellae of the strips and therefore a longer life.
• Increases wet adhesion to the substrate
• The minimum adhesive film forming temperature is lower (0°C);
• The safety of winter bonding increases.

The consequences of using the wrong adhesive at low temperatures are hard to see on the joint surface. To see what's going on inside the solder, the solder must be sectioned.

Unfortunately, when the wrong low temperature adhesive is used, it does not show immediately on the surface of the solder. If the temperature in the hall is not very low you may think there is no reason to use a special adhesive. However, there are situations where wood brought from an unheated warehouse heats only superficially, not deeply. During pressing, the low temperature inside the wood influences the adhesive and can lower its temperature below the minimum film forming temperature. After pressing the adhesive film will look normal, but in section you will see how the adhesive has turned to dust.

The same applies if, immediately after pressing, the piece is moved to an unheated warehouse. After compression has stopped (recommended to be 2 hours) the chemical reaction continues inside the adhesive film for another week. Only then does the glue achieve maximum tear strength and impermeability. If during this period the piece stays in cold storage, due to the low temperature the adhesive inside the glue freezes and turns into dust. It goes without saying that this leads to a decrease in tear strength, making the solder unsafe.

The D3 adhesive can be converted to D4 by adding 3.5-5% of the D3D4 additive. D4 adhesives are used for joints requiring increased moisture resistance. But about D4 adhesives and the additive that turns a D3 into a D4, in a future article.