Biobased adhesives and sealants in continuous development
The environmental concerns, growth of population and decreasing of fossil resources all affect the development of biobased adhesives and sealants. The adhesive and sealant formulations traditionally rely on fossil fuel based components, however, the newer technologies allow for formulations where the fossil materials are replaced by biobased, renewable materials.
Not only are biobased adhesives and sealants environmentally friendly, but they also posses desired mechanical and chemical properties which contribute to their efficiency. Materials used in bio-based adhesives and sealants include starch, vegetable oils, proteins, lignin and natural resins.
Materials that make up Biobased adhesives and sealants
The raw materials used in biobased adhesives and sealants are derived from biomass mostly produced by the agricultural and silvicultural processes. These materials are climate-neutral without affecting the environment when used in adhesives, sealants and other chemical products. The biobased materials replacing petroleum based polymers, tackifiers and waxes are presented in the table below.
|Biobased material type||Ingredients in biobased adhesives and sealants|
|Tackifiers|| Pine rosin|
Dimerized fatty acids
From biobased to compostable
Some biobased materials are also biodegradable. Especially bio based adhesives use these materials, and when they make up the most of the ingredients, the adhesives become compostable by industrial means. The industry that is currently using the most compostable systems is packaging and paper: especially hot melt adhesives benefit from biodegradability, and the adhesives can be modified to suit heat seal applications as well as sticking tape and labels.
European Norms measure biobased content in adhesives and sealants
When biobased adhesives and sealants first were introduced, there were neither internationally acknowledged standards nor testing for biobased materials. To make it easier to define biobased materials and products that use them, several standards have been developed, the most important ones being the European Standards EN 16785-1 and EN 13432.
- EN 16785-1 verifies biobased content of products in two ways: by radiocarbon analysis and elemental analysis according to CEN/TS 16440 for Carbon- 14 component. The standard EN 16785-1 defines biobased as “derived from biomass”. The biobased adhesives and sealants are thus those partially or entirely made of materials derived from biomass. The standard covers a broad range of products since it is applicable to solid, liquid and gaseous compositions which contain carbon.
- EN 13432 evaluates biodegradability of adhesives and sealants by four tests: biodegradation, disintegration, ecotoxicity and heavy metals. An adhesive or sealants is biodegradable if 90% of the total mass of the adhesive is converted to CO2 within 180 days, the germination rate and plant biomass in the compost are more than 90% of those in the corresponding blank compost, the products resulting from composting process can be used to enrich soil or do not harm floral growth in the area, and the heavy metals in the product do not exceed the limits set in the standard.
Certified bio based adhesives and sealants benefit manufacturers and buyers
Obtaining a biobased certificate helps manufacturers demonstrate the biobased content of their products on the labels. This increases the trustworthiness of the products and company in general.
As for the buyer, it is good to look for products that are biobased certified according to EN 16785 or another similar standard to be sure of the contents of the product.
Interested in bio-based adhesives and sealants?
Biobased adhesives and sealants are gaining more and more share on various markets ranging from wood and construction to paper and packaging. In case you would like to receive more information on biobased products, or like to enquire about a suitable biobased product for your process, do not hesitate to contact us.