Urea formaldehyde

[edit] What is urea formaldehyde?

Urea formaldehyde (UF), also referred to as urea-methanal is a thermosetting resin or polymer that is produced from urea and formaldehyde. Urea being a solid crystal which can be obtained from ammonia and formaldehyde, a highly reactive gas obtained from methane. The polymerization process forms the two into networks of permanently interlinked molecules, creating a material with a strong tensile structiure, hardness, low water absorption aswell as distortion through temperature change. It is primarily used to create resins for moulded products and glues but has also been used with a blowing agent to create insulation products.

[edit] What materials contain urea formaldehyde?

Apart from occurring naturally in solid wood, generally low levels of urea formaldehyde can be found in laminates, textiles, and fabrics aswell as coatings for electrical appliances. Urea formaldehyde is also one of the main adhesives used in engineered wood products such as MDF, OSB, LVL, plywood and so on, although alternatives also now exist. It is relatively cheap to produce but does not react well in combination with timber to higher moisture levels and as such is often used in the manufacture of interior wood products such as furniture panelling, boards, with phenolic resin or phenol formaldehyde being mainly used externally. It has also been used with various blowing agents as a type of rigid insulation product, referred to as urea formaldehyde foam insulation (UFFI) mostly during the 1970s and early 1980s.

[edit] Health concerns associated with urea formaldehyde

Urea formaldehyde (UF) is considered as a formaldehyde releaser, which means it releases or off-gasses formaldehyde to varying degrees and concentrations over time. Formaldehyde being a known human carcinogen, is normally a concern only a higher levels, it is one of the most well-known volatile organic compounds, or VOCs but is present in many household products in small amounts, for example naturally in all forms of timber.

VOCs are organic chemicals that easily vaporise when they are at room temperature, at high levels internally or externally they can cause damage to human health or to the environment. Today VOC detectors are available to measure the levels of different VOCs in the air, in particular formaldehyde gas detectors. The Clean Air (Human Rights) Bill lists acceptable levels of formaldehyde as being 8.6 μg/m3, internally or externally, averaging over the period of a year. 1 µg/m3 means that one cubic metre of air contains one microgram (10-6 grams) of a pollutant.

As such products cotaining high levels of urea formaldehyde such as UFFI, paints and other products have been slowly phased out or reduced in many countries, whilst lower content products such as adhesives are regulated by country such as the EU REACH programme. Some evidence still suggests however that when first installed had the potential to release significant amounts of formaldehyde into indoor air resulting in acute adverse health effects with levels dropping rapidly with time.

Today, today urea formaldehyde associated products are still produced, sometimes referred to as injection foam, dry-resin foam, amino foam, aminoplast foam, tri-polymer foam, dry-resin foam and whilst they bear a relation specific product research should be carried out. Today, there are also more readily available possibilities and tools to measure VOCs in internal environments, post completion, aswell as more rigourous manufacturer regulations, in particularly those products associated with formaldehyde release..

Meanwhile research and develop of alternatives has also led to a number of formaldehyde free or no added formaldehyde(NAF) glue products becoming available as alternatives. In terms of types of rigid foam insulation products there are a of altenatives and yet a wider variety of othetr insulants products on the market.

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