Find out more about polymers in liquid formulations (PLFs)

In simple terms, polymers are long-chain molecules built from smaller repeating units called monomers. Some polymers contain only one type of monomer as their building block; others, known as copolymers, may contain two or more different types of monomer.

The OECD defines a polymer in more detail as: “a substance consisting of molecules characterised by the sequence of one or more types of monomer units and comprising a simple weight majority of molecules containing at least three monomer units which are covalently bound to at least one other monomer unit or other reactant and consist of less than a simple weight majority of molecules of the same molecular weight. Such molecules must be distributed over a range of molecular weights wherein differences in the molecular weight are primarily attributable to differences in the number of monomer units.

In the context of this definition, REACH specifies:

• A ‘monomer unit' means the reacted form of a monomer in a polymer
• The weight percentage of molecules containing three monomer units or above should exceed 50%
• The weight percentage of any molecule of the same molecular weight shall not exceed 50%

A PLF is one of a broad group of polymers that are used in formulations that are liquid during the manufacturing process and/or are liquid up to the point of utilisation. Some common uses of PLFs are as thickeners, emulsifiers and binders within a formulation.

PLFs are used across a wide variety of sectors for both consumer and industrial products. They are important ingredients in sectors such as adhesives and sealants, agriculture, household cleaning, inks and coatings, lubricants, personal care and cosmetic products, and water treatment.

More than 36 million metric tonnes of polymers in liquid formulation (PLFs) are made and used every year, enough to fill over 14,500 Olympic sized swimming pools or Wembley Stadium 32 times over.

Polymers in liquid formulations (PLFs) are found in millions of household and industrial products. They play a vital role in our society by improving food productivity, treating wastewater and protecting buildings, infrastructure and transport, as well as creating consumer products that promote health and wellbeing.

PLFs are used in eight key markets, which have a combined estimated global value of $1.27 trillion. These are: adhesives and sealants, agriculture, household cleaning, inks and coatings, lubricants, paints and coatings, personal care and cosmetics, and water treatment.

A significant proportion of the 36 million tonnes of all PLFs made and sold each year – over 31 million metric tonnes – are sold in the paints and coatings, inks and coatings, and adhesives and sealants markets.

Polymers in liquid formulation (PLFs) are a high value and critically important class of speciality chemicals worth $125 billion to the global economy annually.

More than 36 million metric tonnes of PLFs are made and used every year, enough to fill over 14,500 Olympic sized swimming pools or Wembley Stadium 32 times over. Currently, the most likely destination at the end of their life is waste, which means that the value of PLFs is lost after use.

To ensure that the PLFs sector is economically and environmentally sustainable in the future, new approaches to PLF production, use and end-of-life treatment are needed. This is a challenge that is bigger than any single organisation, market or academic research group.

Manufacturers produce polymers in liquid formulation (PLFs) from a variety of raw materials including natural, bio-based and fossil-derived monomers. Synthetic PLFs are the most commercially significant because of their availability at high volumes, their competitive cost and the highly specialised properties that they deliver. However, in some markets, natural and bio-based materials are growing in use.

Our report Polymers in liquid formulations - opportunities for a sustainable future looks at three key opportunities to increase value for money and improve sustainability:

• Innovation – such as developing biodegradable or naturally sourced alternatives.
• Circular economy – finding ways to reuse waste in new valuable products.
• Improving waste management – capturing PLFs after use.

Our Sustainable Polymers in Liquid Formulation Task Force was established following this report with the purpose: ‘To provide leadership in creating a collaborative and joined-up strategy leading to a step change in innovation towards sustainable PLFs.’

Polymers in liquid formulation (PLFs) are a high value and critically important class of speciality chemicals worth $125 billion to the global economy annually, and are used in eight key markets, which have a combined estimated global value of $1.27 trillion.

Read our reports to see how this figure breaks down between each market.

The polymers in liquid formulation (PLFs) market is technically diverse and complex, comprising hundreds of different polymer types within the categories of acrylic, epoxy resins, polyesters, polysilicones, polyurethanes, radiation curable, vinyl, water-soluble and other low volume polymers.

PLFs are used in formulations that are either liquid, which remain liquid on application and throughout use, or curable, which form solids on application and remain solid in use. These formulation systems can explain key differences in the use and fate of PLFs across different markets.

Both are made from polymers, but while all plastics are polymers, not all polymers are plastics. Polymers in liquid formulation (PLFs) and plastics are different groups of polymers with different uses and properties.

Despite their importance to society and the global economy, and in contrast to the recent intense focus on the sustainability of plastics, there has been very little coordinated effort to highlight the sustainability of PLFs.

Polymers in liquid formulation (PLFs) used in products that do not harden, such as in cosmetics or household cleaners, are likely to enter the environment as they pass through wastewater treatment plants at the end of their life.

PLFs used in curable formulations, such as paints and resins, form solids on application and provide durability over much longer timeframes than other markets. They may remain on materials after use and either enter waste streams at the end of their life, such as landfill, or enter the environment during use.